ANTIMOCROBIALS

Definition of Terms
Antagonistic Interactions: Concurrent administration of two drugs causes harmful effects such as a decrease of drug activity, decreased
therapeutic levels due to increased metabolism and elimination, or increased potential for toxicity due to decreased metabolism and elimination.
An example of an antagonistic interaction is taking antacids with antibiotics, causing decreased absorption of the antibiotic.

Antifungal: Medications that are used to treat fungal infections. For example, nystatin is used to treat Candida Albicans, a fungal infection.

Antiviral: Medications used to treat viral infections. For example, Tamiflu is used to treat influenza.

Bactericidal: Antimicrobial drugs that kill their target bacteria.

Bacteriostatic: Antimicrobial drugs that cause bacteria to stop reproducing but may not ultimately kill the bacteria.

Black Box Warnings: The strongest warnings issued by the Federal Drug Administration (FDA) that signify the drug carries a significant risk of
serious or life-threatening adverse effects.

Broad-Spectrum Antimicrobial: An antibiotic that targets a wide variety of bacterial pathogens, including both gram-positive and gram-
negative species.

Clostridium Difficile (C-diff): Clostridium difficile causes pseudomembranous colitis, a superinfection that can be caused by broad spectrum
antibiotic therapy.

Culture: A test performed on various body substances for the presence of bacteria or fungus.

Dose Dependent: A more significant response occurs in the body when the medication is administered in large doses to provide a large amount
of medication to the site of infection for a short period of time.

Gram-Positive: Gram-positive bacteria are classified by the color they turn after a chemical called Gram stain is applied to them. Infections
caused by Streptococcus and Staphylococcus bacteria are examples of gram-positive infections.

Gram-Negative: Gram-negative bacteria are classified by the color they turn after a chemical called Gram stain is applied to them. Escherichia
Coli (also known as E. Coli) is an example of a gram-negative infection.

Gram Stain: A test used to quickly diagnose types of bacterial infection. Gram-positive and gram-negative bacteria stain differently because
their cell walls are different. Identification of bacteria as gram positive or gram negative assists the healthcare provider in selecting an appropriate
antibiotic to treat the infection.

Half-Life: The rate at which 50% of a drug is eliminated from the bloodstream.

Indications: The use of a drug for treating a particular condition or disease. The FDA determines if there is enough evidence for a labeled
indication of a drug. Providers may also prescribe medications for off-label indications if there is reasonable scientific evidence that the drug is
effective, but these uses have not been approved by the FDA.

Mechanism of Action: The way in which a drug affects microbes at the cellular level.

Methicillin-Resistant S. Aureus (MRSA): An infection caused by Methicillin-resistant Staphylococcus aureus that is difficult to treat because it
exhibits resistance to nearly all available antibiotics.

Narrow-Spectrum Antimicrobial: An antibiotic that targets only specific subsets of bacterial pathogens.

Pathogen: An organism causing disease to its host.

Prototype: A common individual drug that represents a drug class or group of medications having similar chemical structures, mechanism of
actions, and modes of action.

Resistance: A characteristic of bacteria when sensitivity analysis is performed demonstrating lack of effective treatment by a particular
antibiotic.

Sensitivity Analysis: A test performed in addition to a culture to select an effective antibiotic to treat a microorganism.
Superinfection: A secondary infection in a patient having a preexisting infection. C-diff and yeast infections as a result of antibiotic therapy are
examples of superinfections.

Synergistic Interaction: Concurrent drug administration producing a synergistic interaction that is better than the efficacy of either drug alone.
An example of synergistic drug combinations is trimethoprim and sulfamethoxazole (Bactrim).

Time Dependent: Time dependency occurs when greater therapeutic effects are seen with lower blood levels over a longer period of time.
Vancomycin-Resistant S. Aureus (VRSA): An infection caused by Vancomycin-resistant Staphylococcus aureus that is difficult to treat
because it exhibits resistance to nearly all available antibiotics.

ANTIMICROBIAL

Bacteria are found in nearly every habitat on earth, including within and on humans. Most bacteria are harmless or considered helpful, but some
are pathogens.

A pathogen is defined as an organism causing disease to its host. Pathogens, when overgrown, can cause significant health problems or even
death for patients.

Bacteria may be identified when a patient has an infection by using a culture and sensitivity test or a gram stain test. Antimicrobials may be
classified as broad-spectrum or narrow-spectrum, based on the variety of bacteria they effectively treat.

Additionally, antibiotics may be bacteriostatic or bactericidal in terms of how it targets the bacteria. Finally, the mechanism of action is also
considered in the selection of an antibiotic.

Culture and Sensitivity

When a patient presents signs or symptoms of an infection, healthcare providers will begin the detective work needed to identify the source of the
infection.

A culture is a test performed to examine different body substances for the presence of bacteria or fungus.
These culture samples are commonly collected from a patient’s blood, urine, sputum, wound bed, etc. Nurses are commonly responsible for the
collection of culture samples and must be conscientious to collect the sample prior to the administration of antibiotics.

Antibiotic administration prior to a culture can result in a delayed identification of the organism and complicate the patient’s recovery. Once
culture samples are collected, they are then incubated in a solution that promotes bacterial or fungal growth and spread onto a special culture
plate. Clinical microbiologists subsequently monitor the culture for signs of organism growth to aid in the diagnosis of the infectious pathogen.

A sensitivity analysis is often performed to select an effective antibiotic to treat the microorganism.
If the organism shows resistance to the antibiotics used in the test, those antibiotics will not provide effective treatment for the patient’s
infection. Sometimes a patient may begin antibiotic treatment for an infection, but will be switched to a different, more effective antibiotic based
on the culture and sensitivity results.
Gram Positive vs. Gram Negative

A gram stain is another type of test that is used to assist in classification of pathogens.
Gram stains are useful for quickly identifying if bacteria are “gram positive” or “gram negative,” based on the staining patterns of their cellular
walls.
Utilizing gram stain allows microbiologists to look for characteristic violet (Gram +) or red/pink (Gram -) staining patterns when they examine
the organisms under a microscope.
Identification of bacteria as gram positive or gram-negative assists the healthcare provider in quickly selecting an appropriate antibiotic to treat
the infection.

SAMPLE GRAM POSITIVE INFECTIONS

Gram Stain Specimen Streptococcus

Streptococcus, the name which comes from the Greek word for twisted chain, is responsible for many types of infectious diseases in humans.
Streptococcus is an example of a Gram + infection and is identified by its ability to lyse, or breakdown, red blood cells when grown on blood
agar.
S. pyogenes is a type of β-hemolytic Streptococcus. This species is considered a pyogenic pathogen because of the associated pus production
observed with infections it causes.
S. pyogenes is the most common cause of bacterial pharyngitis (strep throat); it is also a common cause of various skin infections that can be
relatively mild (e.g., impetigo) or life threatening (e.g., necrotizing fasciitis, also known as flesh-eating disease).

Staphylococcus aureus illustrates the typical “grape-like” clustering of cells. This is an image of Streptococcus undergoing gram staining.

Staphylococcus is a second example of a Gram + bacteria. The bacteria Staphylococcus comes from a Greek word for bunches of grapes, which
describes their microscopic appearance in culture.
Strains of S. aureus cause a wide variety of infections in humans, including skin infections that produce boils, carbuncles, cellulitis, or impetigo.
Many strains of S. aureus have developed resistance to antibiotics.

Some antibiotic-resistant strains are designated as methicillin-resistant S. aureus (MRSA) and vancomycin-resistant S. aureus (VRSA).
These strains are some of the most difficult to treat because they exhibit resistance to nearly all available antibiotics, not just methicillin and
vancomycin. Because they are difficult to treat with antibiotics, infections can be lethal.

MRSA and VRSA are also contagious, posing a serious threat in hospitals, nursing homes, dialysis facilities, and other places where there are
large populations of elderly, bedridden, and/or immunocompromised patients.

SAMPLE GRAM NEGATIVE INFECTIONS

Neisseria meningitidis growing in colonies on a chocolate agar plate

Gram negative bacteria often grow between aerobic and anaerobic areas (such as in the intestines).
Some gram-negative bacteria cause severe, sometimes life-threatening disease.
The genus Neisseria, for example, includes the bacteria N. gonorrhoeae, the causative agent of the sexually transmitted infection gonorrhea,
and N. meningitides, the causative agent of bacterial meningitis. Another common gram negative infection that is seen in hospitalized patients
is Escherichia coli (E. Coli). This is a frequent culprit for urinary tract infections due to its presence in the GI tract.
Broad-Spectrum vs. Narrow-Spectrum Antimicrobials

Spectrum of activity is one of the factors that providers use when selecting antibiotics to treat a patient’s infection.

A narrow-spectrum antimicrobial targets only specific subsets of bacterial pathogens.

For example, some narrow-spectrum drugs only target gram positive bacteria, but others target only gram-negative bacteria. If the pathogen
causing infection has been identified in a culture and sensitivity test, it is best to use a narrow-spectrum antimicrobial and minimize collateral
damage to the normal microbacteria.

A broad-spectrum antimicrobial targets a wide variety of bacterial pathogens, including both gram positive and gram-negative species, and is
frequently used to cover a wide range of potential pathogens while waiting on the laboratory identification of the infecting pathogen.
Broad-spectrum antimicrobials are also used for polymicrobial infections (a mixed infection with multiple bacterial species) or as prophylactic
prevention of infections with surgery/invasive procedures. Finally, broad-spectrum antimicrobials may be selected to treat an infection when a
narrow-spectrum drug fails because of development of drug resistance by the target pathogen.

Clostridium difficile, a gram-positive, rod-shaped bacterium, causes severe colitis and diarrhea, often after the normal gut microbiota is
eradicated by antibiotics

One risk associated with using broad-spectrum antimicrobials is that they will also target a broad spectrum of the normal microbacteria that can
cause diarrhea. They also increase the risk of a superinfection, a secondary infection in a patient having a preexisting infection.

A superinfection develops when the antibacterial intended for the preexisting infection kills the protective microbiota, allowing another pathogen
resistant to the antibacterial to proliferate and cause a secondary infection. Common examples of superinfections that develop as a result of
antimicrobial use include yeast infections (candidiasis) and pseudomembranous colitis caused by Clostridium difficile (C-diff), which can be
fatal.
Probiotics, such as lactobacillus, are commonly used for individuals with C-diff to introduce normal bacteria into the gastrointestinal system and
improve bowel function.
 A broad-spectrum antibiotic will treat gram positive and gram-negative bacteria.
 A narrow-spectrum antibiotic will treat either gram positive or gram-negative bacteria.
 If a patient is started on an antibiotic that is gram + and the culture identifies a gram – organism, the medication will not improve the
patient’s status. The selection of an incorrect antibiotic can lead to adverse reactions and increase bacterial resistance.
 At times, a broad-spectrum antibiotic may be administered prior to receiving the culture report due to the severity of the illness of the
patient. Once the culture is reported, the antibiotic therapy is tailored to the patient. It is the nurse’s responsibility to review culture
results and ensure that the results have been communicated to the prescribing provider.

Antibacterials Actions — Bacteriostatic vs. Bactericidal

 When a provider selects an antibacterial drug, it is important to consider how and where the drug will ultimately target the bacteria.
Antibacterial drugs can be either bacteriostatic or bactericidal in their interactions with the offending bacteria.
 Bacteriostatic drugs cause bacteria to stop reproducing; however, they may not ultimately kill the bacteria. In
contrast, bactericidal drugs kill their target bacteria.
 The decision about whether to use a bacteriostatic or bactericidal drug often depends on the type of infection and the overall immune
status of the patient. In a healthy patient with strong immune defenses, both bacteriostatic and bactericidal drugs can be effective in
achieving clinical cure. However, when a patient is immunocompromised, a bactericidal drug is essential for the successful treatment
of infections. Regardless of the immune status of the patient, life-threatening infections such as acute endocarditis require the use of a
bactericidal drug to eliminate all offending bacteria.
 Mechanism of Action
 Another consideration in the selection of an antibacterial drug is the drug’s mechanism of action. Each class of antibacterial drugs has
a unique mechanism of action, the way in which a drug affects microbes at the cellular level. For example, cephalosporins act on the
 integrity of the cell wall. In contrast, aminoglycosides impact ribosome function and inhibit protein synthesis, which stops the
proliferation of cells. See Figure 3.5 for a summary of how various antibiotics affect the cell wall, the plasma membrane, the
ribosomes, the metabolic pathways, or DNA synthesis of bacteria.

Various mechanisms of actions of antimicrobial medication

Antiviral

 Similar to antibacterial medications, antiviral drugs directly impact interaction and reproduction of the offending microorganism.
Antibacterial medications are required for treating bacterial infections; antivirals treat specific viral infections. For example,
oseltamivir (Tamiflu) is commonly prescribed to treat influenza. Unlike antimicrobials, antiviral medications do not kill the offending
virus, but they work to reduce replication and development of the virus.

Antifungal

 Antifungal, or antimycotic agents, are medications that are used to treat fungal infections. These medications work by killing the
cells of the fungus or inhibiting the reproduction of the cells. Unlike antibacterial and antiviral medications, many antifungals are
applied topically to the affected area. Fungal infections commonly affect surface areas of the body, including the toes, nails, mouth,
groin, etc. For example, Candida albicans is a type of fungi that when overgrown in the mouth produces oral thrush. Patients
experiencing thrush may be prescribed oral antifungal swish and spit medication such as nystatin.

Penicillins
Penicillin was the first antibiotic discovered and its detection came as a bit of an accident. In 1928, Alexander Fleming, a professor of
bacteriology at St. Mary’s Hospital in London, discovered penicillin accidentally growing in a petri dish in his lab.

The penicillin was the result of mold juice that had grown there inadvertently. Fleming noted that this “mold juice” inhibited the growth of
Staphylococcus bacteria that was previously growing in the petri dish. Subsequently, the first antibiotic discovery was made.

Indications: Penicillins are prescribed to treat a variety of infectious processes such as Streptococcal infections, Pneumococcal infections, and
Staphylococcal infections. Penicillins may be administered orally, IV, or intramuscularly.

Mechanism of Action: Penicillins are bactericidal and kill bacteria by interfering with the synthesis of proteins needed in their cellular
walls. When the bacterial cell wall is impaired, the cell is rapidly broken down and destroyed.

Specific Administration Considerations: In addition to general antimicrobial administration considerations, it is important to monitor patients
who receive penicillins for signs of superinfections such as C-diff or yeast infections. There is also a cross-sensitivity for patients allergic to
cephalosporins. It is important to remember that patients who are prescribed high doses of penicillin may experience significant coagulation
abnormalities. Other notable drug interactions include the use of diuretic therapy with penicillin. Penicillin contains a significant amount of
potassium. Patients receiving potassium-sparing diuretics or supplementation should be monitored for signs of hyperkalemia. Penicillin is best
absorbed on an empty stomach; however, many patients may experience GI upset and subsequently take the medication with food.

Patient Teaching & Education: The patient should notify the health care provider (HCP) if fever or diarrhea develops, especially if the stool
contains blood, pus, or mucus. Advise the patient not to treat diarrhea without advice from HCP. If GI upset occurs, the patient may take the
medication with meals but should avoid taking with citrus-based products, which can impede absorption. Additionally, patients should be
instructed to chew oral chewable tablets thoroughly before swallowing. The patient should report a rash or any signs of superinfection (black,
furry overgrowth on tongue; vaginal itching or discharge; loose or foul-smelling stool).

Patients should be instructed to take medication around the clock and to finish the drug completely as directed. Doses should be spaced evenly to
achieve the desired therapeutic effect. Additionally, patients should receive instruction to not share medication and that any sharing of
medications may be dangerous. Patients with a history of rheumatic heart disease or valve replacement should receive instruction regarding the
importance of using antimicrobial prophylaxis before invasive medical or dental procedures. Female patients taking oral contraceptives should
use an alternative form of contraception during therapy with amoxicillin and until next period. Patients should notify their HCP if symptoms do
not improve.

Penicillin

Administration Therapeutic
Class/Subclass Prototype-Generic Side/Adverse Effects
Considerations Effects

Common: nausea,
vomiting, epigastric
distress, diarrhea, and
Check for allergies
black hairy tongue
to penicillin or
cephalosporins Monitor for C-diff,
Monitor for
candidiasis, and
Obtain culture, if systemic signs of hyperkalemia
ordered, before first infection:
penicillin V (PO) dose Hypersensitivity: Rash
-WBCs (maculopapular to
penicillin G (IV) Take w/ full glass of exfoliative dermatitis),
Penicillin water; no acidic urticaria, laryngeal
-Temp edema, and
amoxicillin juice
anaphylaxis
-Culture results
piperacillin/tazobactam (combination product) Best absorbed orally
on empty stomach; SAFETY: If an allergic
give with food if Monitor actual reaction occurs,
stomach upset site of infection penicillin should be
for improvement discontinued and
appropriate therapy
If high doses;
instituted. Serious
monitor INR,
anaphylactic reactions
platelets, PT
require emergency
treatment with
epinephrine and airway
management

Cephalosporins
Cephalosporins are a slightly modified chemical “twin” to penicillins due to their beta lactam chemical structure. Because of these similarities,
some patients who have allergies to penicillins may experience cross-sensitivity to cephalosporins.

Indications: Cephalosporins are used to treat skin and skin-structure infections, bone infections, genitourinary infections, otitis media, and
community-acquired respiratory tract infections.

Mechanism of Action: Cephalosporins are typically bactericidal and are similar to penicillin in their action within the cell wall. Cephalosporins
are sometimes grouped into “generations” by their antimicrobial properties.

The 1st-generation drugs are effective mainly against gram-positive organisms. Higher generations generally have expanded spectra against
aerobic gram-negative bacilli.

The 5th-generation cephalosporins are active against methicillin-resistant Staphylococcus aureus (MRSA) or other complicated infections.

Specific Administration Considerations: Patients who are allergic to pencillins may also be allergic to cephalosporins. Patients who consume
cephalosporins while drinking alcoholic beverages may experience disulfiram-like reactions including severe headache, flushing, nausea,
vomiting, etc. Additionally, like penicillins, cephalosporins may interfere with coagulability and increase a patient’s risk of bleeding.
Cephalosporin dosing may require adjustment for patients experiencing renal impairment. Blood urea nitrogen (BUN) and creatinine should be
monitored carefully to identify signs of nephrotoxicity.

Patient Teaching & Education: Patients who are prescribed cephalosporins should be specifically cautioned about a disulfiram reaction, which
can occur when alcohol is ingested while taking the medication. Additionally, individuals should be instructed to monitor for rash and signs of
superinfection (such as black, furry overgrowth on tongue; vaginal itching or discharge; loose or foul-smelling stool) and report to the prescribing
provider.

It is also important to note that cephalosporin can enter breastmilk and may alter bowel flora of the infant. Thus, use during breastfeeding is often
discouraged.

Cephalosporin

Therapeutic
Class/Subclass Prototype/Generics Administration Considerations Side/Adverse Effects
Effects

Common side effects:

1st generation:
-Nausea
cephalexin
Check for allergies, including if allergic -Vomiting
Cefazolin to penicillin Monitor for
-Epigastric distress
systemic signs of
2nd generation: Dosage adjustment if renal impairment
infection: -Diarrhea
cefprozil Use with caution with seizure disorder
-WBCs Monitor for:
Cephalosporins 3rd generation: PO: Administer without regard to food;
– Fever -Rash
if GI distress, give with food
ceftriaxone Monitor actual site -C-diff
IV: Reconstitute drug with sterile water
of infection
or normal saline; shake well until
4th generation:
dissolved. Inject into large vein or free- Nephrotoxicity if pre-
flowing IV solution over 3-5 minutes Monitor culture existing renal disease
cefepime results, if obtained
Drug interaction: anticoagulants Elevated INR and
5th generation:
bleeding risk

ceftolozane
Development of
hemolytic anemia

Carbapenems

Carbapenems are a beta- lactam “cousin” to penicillins and cephalosporins.

Indications: Carbapenems are useful for treating life-threatening, multidrug-resistant infections due to their broad spectrum of activity. These
antibiotics are effective in treating gram-positive and gram-negative infections. Because of their broad spectrum of activity, these medications can
be especially useful for treating complex hospital-acquired infections or for patients who are immunocompromised.

Mechanism of Action: Carbapenems are typically bactericidal and work by inhibiting the synthesis of the bacterial cell wall.

Specific Administration Considerations: Carbapenems are similar to cephalosporins. Cross sensitivity may occur in patients allergic to
pencillin or cephalosporins.

Patient Teaching & Education: Patients should monitor for signs of superinfection and report any occurrence to the provider. If a patient
experiences fever and bloody diarrhea, they should contact the provider immediately. The patient should also be advised that side effects can
occur even weeks after the medication is discontinued.[2]
 Carbapenem

Class/Subclass Prototype/Generic Administration Considerations Therapeutic Effects Side/Adverse Effects

Carbapenems imipenem Monitor for systemic Similar to cephalosporins

Route: IV signs of infection:

Check for allergies, including -WBCs

penicillin and cephalosporins
-Fever
Dosage adjustment if renal
impairment Monitor actual site of
infection
Use with caution with seizure
disorder or renal dysfunction Monitor culture results, if
obtained

Like penicillins, cephalosporins, and carbapenems, monobactams also have a beta-lactam ring structure.

Indications: Monobactams are narrow-spectrum antibacterial medications that are used primarily to treat gram-negative bacteria such as
Pseudomonas aeruginosa.

Mechanism of Action: Monobactams are bactericidal and work to inhibit bacterial cell wall synthesis.

Specific Administration Considerations: Patients taking monobactams may experience adverse effects similar to other beta-lactam
medications, so nurses should monitor for GI symptoms, skin sensitivities, and coagulation abnormalities.

Patient Teaching & Education: Patients should monitor for signs of superinfection and report any occurrence to the provider. If the patient
experiences fever and bloody diarrhea, they should contact the provider immediately. The patient should also be advised to notify the provider
immediately if symptoms progress or if any sign of allergic response occurs.

Monobactam

Class/Subclass Prototype/Generic Administration Considerations Therapeutic Effects Side/Adverse Effects

Monitor for systemic

signs of infection:

Check for allergies to any beta lactams -WBCs

– penicillin, cephalosporins, or Similar to
Monobactams aztreonam -Fever
carbapenems cephalosporins
Monitor actual site of
Can be administered IM, IV, or via infection
inhalation
Monitor culture
results, if obtained

Sulfonamides are one of the oldest broad-spectrum antimicrobial agents that work by competitively inhibiting bacterial metabolic enzymes
needed for bacterial function.

Indications: Sulfonamides are used to treat urinary tract infections, otitis media, acute exacerbations of chronic bronchitis, and travelers’
diarrhea.
Mechanism of Action: This mechanism of action provides bacteriostatic inhibition of growth against a wide spectrum of gram-positive and
gram-negative pathogens.

Specific Administration Considerations: Allergic reactions to sulfonamide medications are common and, therefore, patients should be
monitored carefully for adverse effects including delayed hypersensitivity reactions. Sulfonamide medications increase the risk of crystalluria that
can cause kidney stones or decreased kidney function; therefore, patients should increase their water intake while taking these medications.

Patient Teaching & Education: The patient should receive education to complete the full prescribed dose of medications and take measures to
not skip doses. If a dose is missed, the patient should take the missed dose as soon as possible unless it is near the next dosing time. The
medication can cause increased photosensitivity, and patients should be educated to use sunscreen and protective clothing with sun exposure.
The patient should also report any rash, sore throat, fever, or mouth sores that might occur. Unusual bleeding or bruising should also be reported
to the provider. If patients are receiving prolonged therapy, they may require platelet count monitoring.

Sulfonamides

Administration Therapeutic
Class/Subclass Prototype/Generic Side/Adverse Effects
Considerations Effects

Check for allergies

Dose adjustment for renal

impairment

Administer PO with 8 oz of Monitor for

water
systemic signs of
Monitor urine output and for infection:
SAFETY:
cloudiness or crystals
-WBCs
Sulfonamides, including
Do not administer IM
trimethoprim – sulfonamide-containing products
Sulfonamides -Fever such as sulfamethoxaole
sulfamethoxazole Use cautiously with cardiac /trimethoprim, should be
antidysrhythmics Monitor actual discontinued at the first
site of infection appearance of skin rash of any
Use cautiously with oral sign of adverse reaction
antidiabetics; may increase Monitor culture
hypoglycemic effects. Monitor results, if
glucose level carefully obtained

Use cautiously with

anticoagulant medications such
as warfarin; may increase risk
of bleeding. Monitor INR and
patient for signs of bleeding

Indications: Fluoroquinolones may be used to treat pneumonia or complicated skin or urinary tract infections.

Mechanism of Action: Fluoroquinolones are a synthetic antibacterial medication that work by inhibiting the bacterial DNA replication. They are
bacteriocidal due to the action they take against the DNA of the bacterial cell wall. Many fluoroquinolones are broad spectrum and effective
against a wide variety of both gram-positive and gram-negative bacteria.

Specific Administration Considerations: Patients taking oral fluoroquinolones should avoid the use of antacid medication as antacids
significantly impede absorption. Patients should also be instructed to take oral fluoroquinolones with a full glass of water two hours before or
after meals to enhance absorption and prevent crystalluria. Fluoroquinolone therapy is contraindicated in children except for complicated UTIs,
pyelonephritis, plague, or post Anthrax exposure and should be used cautiously in pregnancy.

Black Box Warning: Black Box Warnings are the strongest warnings issued by the Federal Drug Association (FDA) and signify that the
medical studies have indicated that the drug carries a significant risk of serious or life-threatening adverse effects.

Fluoroquinolones, including levofloxacin, have been associated with disabling and potentially irreversible serious adverse reactions, including:
  Tendinitis and tendon rupture
 Peripheral neuropathy
 Central nervous system effects
 Exacerbation of muscle weakness in patients with myasthenia gravis

In patients who experience any of these serious adverse reactions, discontinue the medication immediately, and avoid the use of
fluoroquinolones.

Patient Teaching & Education: All patients on fluoroquinolone therapy should be instructed to avoid direct and indirect sunlight due to the
photosensitivity that can be experienced while on these medications. The patient should take measures to ensure that dosages are spaced evenly
throughout the day and that fluid balance is maintained. It is important to maintain an intake of 1500mL-2000mL per day while taking the
medication. The patient should be advised that medications containing calcium, aluminum, iron, or zinc may impair absorption and should be
avoided. Other side effects of fluoroquinolones increase drowsiness. Additionally, the patient should be cautioned to monitor for episodes of
fainting or decreased heart rate and report any history of prolonged QT syndrome. If a patient notices peripheral neuropathy occurring, this
should be reported to the healthcare provider. Additional side effects to monitor include increased tendon pain, jaundice, rash, or mood changes.

Fluoroquinolone

Administration Therapeutic
Class/Subclass Prototype/Generic Side/Adverse Effects
Considerations Effects

Discontinue immediately if
Check for allergies tendonitis, tendon rupture,
Monitor for peripheral neuropathy, CNS
Give with plenty of fluids
systemic signs of effects, or muscle weakness in
Oral: Administer 2 hours infection: patients with Myasthenia Gravis
before or after meals,
antacid, or iron -WBCs Monitor for:

Fluoroquinolones levofloxacin IV: Infuse 500 mg or less -Fever -GI upset

over 60 minutes and doses
of 750 mg over 90 minutes
Monitor actual site -Hypersensitivity
of infection
Dosage adjustment if renal
or hepatic impairment -Photosensitivity
Monitor culture
results, if obtained
Use cautiously if history of -Hypoglycemia
seizures
-C-diff

Macrolides are complex antibacterial broad-spectrum medications that are effective against both gram-positive and gram-negative bacteria.

Mechanism of Action: Macrolides inhibit RNA protein synthesis and suppress reproduction of the bacteria. Macrolides are bacteriostatic as they
do not actually kill bacteria, but inhibit additional growth and allow the body’s immune system to kill the offending bacteria.

Indications: Macrolides are often used for respiratory infections, otitis media, pelvic inflammatory infections, and Chlamydia.

Specific Administration Considerations: Macrolides can have significant impact on liver function and should be used cautiously in patients
with liver disease or impairment.

Patient Teaching & Education: GI upset is common and patients can be advised to take medication with food. Patients should also be advised
to avoid excessive sunlight and to wear protective clothing and use sunscreen when outside, as well as to report any adverse reactions
immediately. Advise patients to report symptoms of chest pain, palpitations, or yellowing of eyes or skin. Additionally, patients should be
advised that these medications can cause drowsiness.

Macrolides
 Therapeutic
Class/Subclass Prototype/Generic Administration Considerations Side/Adverse Effects
Effects

GI upset

Check for allergies Hypersensitivity

Monitor for
PO: Reconstitute suspension with water. Photosensitivity
Can be given with or without food. Take systemic signs of
with food if GI upset occurs infection:
Discontinue
erythromycin immediately if:
Macrolides IV: Reconstitute and shake until well -WBCs
dissolved. Dilute as instructed. Infuse a
azithromycin -QT prolongation or
500-mg dose of azithromycin IV over 1 -Fever dysrhythmias
hour or longer. Never give as a bolus or
IM injection
Monitor actual site -Signs of liver damage
of infection or jaundice
May prolong QT interval segment.
Monitor for dysrhythmias
-Onset or worsening of
myasthenia gravis

Aminoglycosides are a potent broad spectrum of antibiotics that are useful for treating severe infections. Many aminoglycosides are poorly
absorbed in the GI tract; therefore, the majority are given IV or IM. Aminoglycosides are potentially nephrotoxic and neurotoxic. They should be
administered cautiously. Blood peak and trough levels should be performed to titrate a safe dose for each patient.

Indications: Streptomycin is used for streptococcal endocarditis and a second line treatment for tuberculosis. Neomycin is used in the treatment
of hepatic encephalopathy as adjunct therapy to lower ammonia levels and is also used as a bowel prep for colon procedures.

Mechanism of Action: Aminoglycosides are bactericidal and bind with the area of the ribosome known as the 30S subunit, inhibiting protein
synthesis in the cell wall and resulting in bacterial death. Aminoglycosides may be given with beta-lactam medications to facilitate transport of
aminoglycoside across the cellular membrane, resulting in a synergistic effect and increasing drug effectiveness.

Medications that inhibit protein synthesis

Special Administration Considerations: Aminoglycosides can result in many adverse effects for the patient and, therefore, the nurse should
monitor the patient carefully for signs of emerging concerns. Peak and trough levels are used to titrate this medication to a safe dose.
Aminoglycosides can be nephrotoxic (damaging to kidney), neurotoxic (damaging to the nervous system), and ototoxic (damaging to the ear).
Nurses should monitor the patient receiving aminoglycosides for signs of decreased renal function such as declining urine output and increasing
blood urea nitrogen (BUN), creatinine, and declining glomerular filtration rate (GFR). Indications of damage to the neurological system may be
assessed as increasing peripheral numbness or tingling in the extremities. Additionally, the patient should be carefully assessed for hearing loss or
hearing changes throughout the course of drug administration.

Patient Teaching & Education: Patients receiving aminoglycosides should be advised to monitor for signs of hypersensitivity and auditory
changes. This may include tinnitus and hearing loss. Patients may also experience accompanying vertigo while on the medication. Patients
should be advised to drink plenty of fluids while taking the medication. Female patients should notify their provider if pregnancy is planned or if
they are actively breastfeeding.

Streptomycin and Gentamycin

Administration Therapeutic
Class/Subclass Prototype/Generic Side/Adverse Effects
Considerations Effects

GI upset

Rash
Check for allergies
Report diarrhea immediately
Obtain culture before Monitor for
administering systemic signs of SAFETY:
infection:
IM: Blood sample for peak Nephrotoxicity: monitor renal
level should be obtained 1 to 2 function closely
hours after IM injection; – WBCs
streptomycin
obtain blood for trough level
Aminoglycosides just before next dose Risk for severe neurotoxic
– Fever
gentamicin reactions, especially with renal
impairment. Can result in
Inject in a large muscle Monitor actual respiratory paralysis if given
site of infection soon after anesthesia or muscle
Handle carefully; use gloves to relaxant
prepare Monitor culture
results Risk for ototoxicity, especially
Monitor peak and trough if administered with a loop
levels diuretic

Can cause harm to fetus and

breastfed infants

Tetracyclines are broad-spectrum antibiotics that are bacteriostatic, subsequently inhibiting bacterial growth.

Indications: Tetracycline medications are useful for the treatment of many gram-positive and gram-negative infectious processes yet are limited
due to the significance of side effects experienced by many patients.

Mechanism of Action: Tetracyclines work by penetrating the bacterial cell wall and binding to the 30S ribosome, inhibiting the protein synthesis
required to make the cellular wall.

Special Administration Considerations: Significant side effects of tetracycline drug therapy include photosensitivity, discoloration of
developing teeth and enamel hypoplasia, and renal and liver impairment. Tetracyclines are contraindicated in pregnancy and for children ages 8
and under. Small amounts may be excreted in breast milk.

Patient Teaching & Education: Patients should be instructed to avoid direct sunlight exposure and wear sunscreen to prevent skin sensitivities.
Additionally, it is important for patients to be educated regarding potential impaired absorption of tetracycline with the use of dairy products.
Patients who are on oral contraceptives should be educated that tetracyclines may impede the effectiveness of the oral contraceptive and an
alternative measure of birth control should be utilized while on the antibiotic. Female patients must be aware to immediately stop tetracycline if
they become pregnant. Expired tetracycline should be immediately disposed of as it can become toxic.

Tetracycline

Therapeutic
Class/Subclass Prototype/Generic Administration Considerations Side/Adverse Effects
Effects

Tetracyclines tetracycline Check allergies Monitor for Gastrointestinal symptoms

systemic signs of
 Alert: Check expiration date. Using
outdated or deteriorated drug has
been linked to severe reversible
nephrotoxicity (Fanconi syndrome)

Effectiveness is reduced when drug

is given with milk or other dairy
products, antacids, or iron products C-diff

For best drug absorption, give drug Photosensitivity

with a full glass of water on an
empty stomach at least 1 hour before infection: Oral candidiasis
or 2 hours after meals
-WBCs Permanent teeth
Give drug at least 1 hour before discoloration if given to
bedtime to prevent esophageal – Fever patients < 8 y.o.
irritation or ulceration
Monitor actual site Intracranial hypertension:
Use caution with renal or hepatic of infection Monitor for headache,
impairment blurred vision, diplopia, and
vision loss
Avoid using in children younger
than age 8 because drug may cause Decreased effectiveness of
permanent discoloration of teeth, oral contraceptives
enamel defects, and bone growth
retardation

Avoid in pregnancy due to toxic

effects on the developing fetus
(often related to retardation of
skeletal development and teeth)

Unlike the complex structure of fungi or protozoa, viral structure is simple. There are several subclasses of antiviral medications: antiherpes,
antiinfluenza, anti-hepatitis, and antiretrovirals. Each subclass will be discussed in more detail below.

Subclass: Antiherpes

Indications: Acyclovir (Zovirax) and its derivatives are frequently used for the treatment of herpes and varicella virus infections, including
genital herpes, chickenpox, shingles, Epstein-Barr virus infections, and cytomegalovirus infections.

Mechanism of Action: Acyclovir causes termination of the DNA chain during the viral replication process. Acyclovir can be administered either
topically or systemically, depending on the infection.

Special Administration Considerations: Acyclovir use may result in nephrotoxicity.

Patient Teaching & Education: Patients who are being treated with antiviral therapy should be instructed about the importance of medication
compliance. They may also experience significant fatigue, so periods of rest should be encouraged.

Subclass: AntiInfluenza

Indications: Tamiflu (oseltamivir) is used to target the influenza virus by blocking the release of the virus from the infected cells.

Mechanism of Action: Tamiflu prevents the release of virus from infected cells.

Special Administration Considerations: This medication does not cure influenza but can decrease flu symptoms and shorten the duration of
illness if taken in a timely manner. Patients are prescribed the medication for prophylaxis against infection, known exposure, or to lessen the
course of the illness. If patients experience flu-like symptoms, it is critical that they start treatment within 48 hours of symptom onset.
Patient Teaching & Education: Patients who are being treated with antiviral therapy should be instructed about the importance of medication
compliance. They may also experience significant fatigue, so periods of rest should be encouraged.

The influenza virus is one of the few RNA viruses that replicates in the nucleus of cells. Antivirals block the release stage.

Influenza virus replication stages

Subclass: Antiretrovirals

Viruses with complex life cycles, such as HIV, can be more difficult to treat. These types of viruses require the use of antiretroviral medications
that block viral replication. Additionally, antiretrovirals fall under the class of antiviral medications.

HIV attaches to a cell surface receptor of an immune cell and fuses with the cell membrane. Viral contents are released into the cell, where viral
enzymes convert the single-stranded RNA genome into DNA and incorporate it into the host genome

Indications: Antiretrovirals are used for the treatment of illnesses like HIV.

Mechanism of Action: Antiretrovirals impede virus replication.

Special Administration Considerations: Many antiretrovirals may impact renal function; therefore, the patient’s urine output and renal labs
should be monitored carefully for signs of decreased function.

Patient Teaching & Education: Patients who are being treated with antiviral therapy should be instructed about the importance of antiretroviral
compliance. They may also experience significant fatigue, so periods of rest should be encouraged.

Acyclovir
 Prototype/
Class/Subclass Administration Considerations Therapeutic Effects Side/Adverse Effects

Generic

Check for allergies

Route: PO, IV, or topical; do not give IM or

subcutaneously (subq)

Drug is not a cure for

Give with food if GI distress GI distress
herpes but improves
IV: Give IV infusion over at least 1 hour to signs and symptoms of Monitor renal function
prevent renal tubular damage in long-term use,
Antivirals: herpes lesions if started
acyclovir especially if renal
Antiherpes early impairment
Use cautiously if renal impairment,
neurological problems, or dehydration
Can be used long term Lowers seizure
for prevention of threshold
Start therapy as early as possible after signs
outbreaks
or symptoms occur

Encourage fluid intake

Avoid sexual contact while lesions present

Oseltamivir

Prototype/
Class/Subclass Administration Considerations Therapeutic Effects Side/Adverse Effects

Generic

GI distress

Serious skin/
Check for allergies hypersensitivity
reactions; discontinue
Route: PO immediately

Antivirals: Monitor for

Must be given within 48 hours of onset of Reduce duration of flu
oseltamivir symptoms neuropsychiatric
AntiInfluenza symptoms symptoms
Agents
Administer with food to avoid GI distress
Use cautiously in patients
with renal failure, chronic
Does not replace need for annual influenza cardiac or respiratory
vaccination diseases, or any medical
condition that may
require imminent
hospitalization

Adefovir

Administration Considerations Therapeutic Effects Side/Adverse Effects

Class/Subclass Prototype/
 Generic

Route: PO
Severe acute
Prolonged therapy (>1 year or indefinitely)
based on patient status exacerbations of

Antivirals: Hepatitis B
Maintain or improve
Offer HIV testing; may promote resistance
adefovir to antiretrovirals in patients with chronic liver function when Nephrotoxicity
Anti-Hepatitis
HBV infection who also have unrecognized active disease is present
Agents
or untreated HIV infection Lactic acidosis

Do not stop taking medication unless Severe hepatomegally

directed. Monitor hepatic function several
months after stopping therapy

Lamuvadine-Zidovudine

Prototype/ Side/Adverse
Class/Subclass Administration Considerations Therapeutic Effects
Effects

Generic

Check for allergies

Lamivudine used to treat HIV-1 infection

contains a higher dose of the active
ingredient than the lamivudine used to
treat chronic HBV infection. Patients with
HIV-1 infection should receive only
dosing forms appropriate for HIV-1
Antivirals: treatment
Decreases chance of Lactic acidosis
Antiretrovirals Use cautiously in patients with renal developing acquired
impairment
lamivudine- immunodeficiency Severe hepatomegaly
Nucleoside–
zidovudine Inform patient that drug doesn’t cure HIV syndrome (AIDS) and HIV-
Stop treatment
infection, that opportunistic infections and related illnesses such as
nucleotide reverse immediately if
other complications of HIV infection may
transcriptase serious infections or cancer pancreatititis
still occur, and that transmission of HIV to
inhibitors others through sexual contact or blood
contamination is still possible. Taking
these medications, along with practicing
safer sex and making other lifestyle
changes, may decrease the risk of
transmitting (spreading) the HIV or
hepatitis B virus to other people

Teach symptoms of pancreatitis

Fungi are important to humans in a variety of ways. Both microscopic and macroscopic fungi have medical relevance, but some pathogenic
species that can cause mycoses (illnesses caused by fungi).
Candida albicans is the causative agent of yeast infections. Some pathogenic fungi are opportunistic, meaning that they mainly cause infections
when the host’s immune defenses are compromised and do not normally cause illness in healthy individuals.

Fungi are important in other ways. They act as decomposers in the environment, and they are critical for the production of certain foods such as
cheeses. Fungi are also major sources of antibiotics, such as penicillin from the fungus Penicillium.

Indications:

Imidazoles are synthetic fungicides commonly used in medical applications and also in agriculture to keep seeds and harvested crops from
molding. Examples include miconazole, ketoconazole, and clotrimazole, which are used to treat fungal skin infections such as ringworm,
specifically tinea pedis (athlete’s foot), tinea cruris (jock itch), and tinea corporis.

Triazole drugs, including fluconazole, can be administered orally or intravenously for the treatment of several types of systemic yeast infections,
including oral thrush and cryptococcal meningitis, both of which are prevalent in patients with AIDS. Triazoles also exhibit more selective
toxicity, compared with the imidazoles, and are associated with fewer side effects.

Allylamines, a structurally different class of synthetic antifungal drugs, are most commonly used topically for the treatment of dermatophytic
skin infections like athlete’s foot, ringworm, and jock itch. Oral treatment with terbinafine is also used for fingernail and toenail fungus, but it can
be associated with the rare side effect of hepatotoxicity.

Polyenes are a class of antifungal agents naturally produced by certain actinomycete soil bacteria and are structurally related to macrolides.
Common examples include nystatin and amphotericin B. Nystatin is typically used as a topical treatment for yeast infections of the skin, mouth,
and vagina, but may also be used for intestinal fungal infections. The drug amphotericin B is used for systemic fungal infections like
aspergillosis, cryptococcal meningitis, histoplasmosis, blastomycosis, and candidiasis. Amphotericin B was the only antifungal drug available for
several decades, but its use has associated serious side effects, including nephrotoxicity.

Mechanism of Action: Antifungals disrupt ergosterol biosynthesis of the cell membrane increasing cellular permeability and causing cell death.

Special Administration Considerations: Administration guidelines will vary depending on the type of fungal infection being treated. It is
important to monitor response of the affected area and examine class specific administration considerations to monitor patient response.

Patient Teaching & Education: The patient should be advised to follow dosage instructions carefully and finish the drug completely, even if
they feel their symptoms have resolved. The patient should report any skin rash, abdominal pain, fever, or diarrhea to the provider. The patient
should monitor carefully for unexplained bruising or bleeding, which may be a sign of liver dysfunction.

Antifungal

Administration
Class/Subclass Prototype/Generic Therapeutic Effects Side/Adverse Effects
Considerations

Improve symptoms of
Check for allergies athlete’s foot (tinea
Antifungals clotrimazole Topical-skin irritation, rash
pedis), jock itch (tinea
Topical cream: apply liberally cruris), or ringworm
twice daily to affected area

Check for allergies

Route: PO/IV
Improve symptoms of
fluconazole Single or multiple doses Hepatotoxicity
yeast infection
Caution if liver dysfunction

Potential for fetal harm

 Cream or aerosol Improve symptoms of
athlete’s foot (tinea
terbinafine Wash affected area with soap External use only
pedis), jock itch (tinea
and water and allow to dry
completely before applying cruris), or ringworm

PO: If order is “‘swish and

swallow,” instruct patient to
hold medication in mouth for
Improve symptoms of
nystatin several minutes before External use only
yeast infection of skin
swallowing

Topical cream/powder: apply

liberally twice daily

Monitor fluid intake and

output; report change in urine
appearance or volume
Check for allergies
Monitor BUN and creatinine
Route: IV levels two or three times
weekly. Kidney damage may
Reconstitute and dilute as be reversible if drug is stopped
directed on packaging at first sign of renal
dysfunction
Administer slowly over
several hours initially and Hydrate patient before
monitor VS every 30 minutes; infusion to reduce risk of
may require premedication Improvement of nephrotoxicity

systemic fungal
amphotericin B Therapy may take several Obtain liver function tests
infection such as once or twice weekly
months
aspergillis
Alert: Different amphotericin Monitor CBC weekly
B preparations aren’t
interchangeable Monitor potassium level
closely and report signs of
Caution if renal impairment hypokalemia

Black Box Warning: Don’t Check calcium and

use to treat noninvasive forms magnesium levels twice
of fungal disease in patients weekly
with normal neutrophil counts
Drug may be ototoxic. Report
evidence of hearing loss,
tinnitus, vertigo, or unsteady
gait

Malaria is a prevalent protozoal disease impacting individuals across the world.

Indications: Antimalarials are used for the prevention or treatment of malaria.

Mechanism of Action: Antimalarial agents work by targeting specific intracellular processes that impact cell development.

Special Administration Considerations: Antimalarial medications may impact hearing and vision so patients should be monitored carefully for
adverse effects. Additionally, antimalarial medications may cause GI upset, so patients should be instructed to take these medications with food.

Patient Teaching & Education: Patients should receive instruction to take medication as prescribed and adhere to the full prescription regimen.
Patients should minimize additional exposure to mosquitoes using preventive means such as repellents, protective clothing, mosquito net, etc.
Patients on chloroquine therapy should also avoid alcohol.

Chloroquine can be extremely toxic to children and should be safely stored and out of reach.

Patients receiving antimalarial therapy may have increased sensitivity to light and should be counseled to wear protective glasses to prevent
ocular damage.

Treatment often requires sustained regimens of six months or greater so patients should be monitored carefully for adherence and compliance.

Chloroquine

Prototype/ Administration
Subclass Therapeutic Effects Side/Adverse Effects
Considerations

Generic

Check for allergies

Contraindicated in patients
hypersensitive to drug and in Changes in vision
those with retinal or visual field Prevention of malaria or
changes Changes in hearing
improvement of an acute
Use cautiously in patients with attack of malaria Monitor renal function closely
severe GI, neurologic, or blood
Antimalarials chloroquine
disorders; hepatic disease or For malaria prevention, Monitor patient for overdose, which
alcoholism; or G6PD deficiency the CDC recommends that can quickly lead to toxic symptoms:
or psoriasis patients take drug for 4 headache, drowsiness, visual
weeks after leaving the disturbances, nausea and vomiting,
Take with food to prevent GI area cardiovascular collapse, shock, and
upset convulsions

In severe or resistant cases,

artesunate IV may be prescribed

Antiprotozoal drugs target infectious protozoans such as Giardia, an intestinal protozoan parasite that infects humans and other mammals,
causing severe diarrhea.

Indications: Metronidazole is an example of an antiprotozoal antibacterial medication gel that is commonly used to treat acne rosacea, bacterial
vaginosis, or trichomonas. Metronidazole IV is used to treat Giardia and also serious anaerobic bacterial infections such as Clostridium difficile
(C-diff).

Mechanism of Action: Many antiprotozoal agents work to inhibit protozoan folic acid synthesis, subsequently impairing the protozoal cell.

Special Administration Considerations: It can be administered PO, parenterally, or topically. Orally is the preferred route for GI infections.
The nurse should monitor the patient carefully for side effects such as seizures, peripheral neuropathies, and dizziness. Psychotic reactions have
been reported with alcoholic patients taking disulfiram.

Patient Teaching & Education

Patients taking antiprotozoal medications should receive education regarding the need for medication compliance and prevention of reinfection.
They should be advised that the medication may cause dizziness and dry mouth. Additionally, the medication may cause darkening of the urine.
They should also avoid alcoholic beverages during medication therapy to prevent a disulfiram-like reaction.

If patients are being treated for protozoal infections such as trichomoniasis, they should be advised that sexual partners might be sources of
reinfection even if asymptomatic. Partners should also receive treatment.[3]

Patients teaching should include the avoidance of alcohol during therapy.

 Metronidazole

Therapeutic Side/Adverse
Class/Subclass Prototype/Generic Administration Considerations
Effects Effects

Check for allergies

Topical, vaginal, PO, or IV Seizures

Don’t give by IV push. Infuse over 30 to Peripheral

Antiprotozoal- 60 minutes Improvement of neuropathy
metrogel
antibacterial symptoms
Contraindications: pregnancy, Psychotic reactions
metronidazole IV hypersensitivity, use of alcohol or
disulfiram during therapy
Hepatotoxicity
Use cautiously with hepatic impairment,
blood dyscrasias or CNS diseases

There are two major groups of parasitic helminths in the human body: the roundworms (Nematoda) and flatworms (Platyhelminthes). See Figure
3.15 for images of a tapeworm and a guinea worm. Of the many species that exist in these groups, about half are parasitic and some are important
human pathogens.

Indications: Anthelmintic medications target parasitic helminths.

Mechanism of Action: Because helminths are multicellular eukaryotes like humans, developing drugs with selective toxicity against them is
extremely challenging. Despite this, several effective classes have been developed. Many anthelmintic medications work by preventing
microtubule formation within the parasitic cell, compromising glucose uptake. Others work by blocking neuronal transmission within the
parasite, subsequently causing starvation, paralysis, and death of the worms. Additionally, many antihelminths inhibit ATP formation and impair
calcium uptake inducing paralysis and death.

Special Administration Considerations: Prolonged therapy using antihelmintic medication can result in liver damage and bone marrow
suppression.

Patient Teaching & Education: Patients on antihelmintic drug therapy should receive special instruction to ensure rigorous hygienic precautions
to minimize the risk of reinfection. They should also wash all bedding, linens, towels, and clothing following treatment to minimize reinfection
risk.
A. The tapeworm Taenia saginata, that infects both cattle and humans. Eggs are microscopic, but the adult tapeworm like the one show here can
reach 4-10 meters, taking up residence in the digestive system.
B. An adult guinea worm, Dracunculus medinensis, is removed through a lesion in the patient’s skin by winding it around a matchstick.

Mebendazole

Therapeutic Side/ Adverse

Class/Subclass Prototype/Generic Administration Considerations
Effects Effects

Contraindicated during pregnancy; may cause

fetal harm
In prolonged

To help prevent reinfection: treatment:

Elimination of
Antihelmintic mebendazole -Hepatic effects
-Wash hands and fingernails with soap often worms
during the day, especially before eating and
after using the toilet -Bone marrow
suppression
-Wash all fruits and vegetables thoroughly or
cook them well

-Wear shoes

M. tuberculosis is the causative agent of tuberculosis (TB), a disease that primarily impacts the lungs but can infect other parts of the body as
well. It has been estimated that one third of the world’s population has been infected with M. tuberculosis and millions of new infections occur
each year.

Treatment of M. tuberculosis is challenging and requires patients to take a combination of drugs for an extended time. Complicating treatment
even further is the development and spread of multidrug-resistant strains of this pathogen.

Indications: Antitubercular medications are selective for mycobacteria work by inhibiting growth or selectively destroying mycobacteria.

Mechanism of Action: They work impacting the synthesis or transcription of mycobacteria RNA or inhibiting the synthesis of mycolic acids in
the cellular wall. Mycobacteria can develop resistance to antitubercular medications; therefore, strict compliance to drug regimen must be
emphasized.
Special Administration Considerations: Antitubicular medications require at least six months of treatment. Many antitubercular medications
may impact liver function, and liver enzymes should be monitored carefully. Other side effects to medication administration include GI
symptoms, peripheral neuropathy, and vision changes.

Patient Teaching/Education: Advise patients that medications must be taken as directed. It is important that patients understand the
significance of continuing drug therapy even after symptoms have resolved to prevent the spread of disease. Drug therapy may be continued for
six months to two years. If a patient notices any change in visual acuity or eye discomfort, it should be reported immediately to the healthcare
provider.

Patients should also be advised to avoid alcohol during antitubercular therapy because of the increased risk of liver toxicity. Foods containing
tyramine such as tuna and Swiss cheese should be avoided.

Isoniazid

Prototype/
Class/Subclass Administration Considerations Therapeutic Effects Side/Adverse Effects

Generic

Direct observed therapy (DOT) may be

initiated to ensure compliance with
long-term therapeutic regimen

Multiple-drug resistant tuberculosis

(i.e., resistance to at least isoniazid and Negative sputum
GI upset
rifampin) presents difficult treatment smears
Antitubercular (also problems. Treatment must be
individualized and based on Hepatotoxicity
known as isoniazid susceptibility studies Prevention or
elimination of TB
antimycobacterials) May decrease
symptoms:
May decrease effectiveness of oral effectiveness of oral
(productive cough,
contraceptives. Patients should be contraceptives
fever, night sweats)
counseled to use alternate form of oral
contraception

Vitamin B6 supplementation is
necessary in some patients for
prevention of peripheral neuropathy

Vancomycin is a glycopeptide commonly used to treat MRSA.

Indications: Vancomycin is a popular glycopeptide that is active against gram-positive bacteria. Vancomycin is commonly used to treat serious
or severe infections when other antibiotics are ineffective or contraindicated, including those caused by MRSA.

Mechanism of Action: Glycopeptides are a class of medications that inhibit bacterial cell wall synthesis.

Special Administration Considerations: It is poorly absorbed from the GI tract, so it must be given by IV to treat a systemic infection. Oral
vancomycin, on the other hand, is used to treat antibiotic-associated clostridium difficile (C-diff).

Vancomycin poses a significant risk to kidney function and hearing; therefore, patients’ trough levels (the lowest concentration reached by a drug
before the next dose is administered) must be monitored carefully for effective IV dosing to avoid complications. Patients receiving IV
vancomycin may also experience a complication known as “red man syndrome” in which they experience a flushing of the skin and a reddish
rash on the upper body when the infusion is administered too rapidly.

Patient Teaching/Education: Patients should be counseled to take medications as directed for the full course of antibacterial therapy. They
should monitor for side effects such as hypersensitivity, tinnitus, hearing loss, and vertigo. Patients should promptly follow-up with their
healthcare provider if no improvement in symptoms is identified.
 Vancomycin

Administration Therapeutic
Class/Subclass Prototype/Generic Side/Adverse Effects
Considerations Effects

Nephrotoxicity

Ototoxicity
Check for allergies
C-diff can occur up to 2
months after therapy ends
Route: IV but PO for Monitor for
C-diff systemic signs of Red-man syndrome can
occur if drug is infused too
infection:
Obtain culture prior to rapidly. Signs and
administering first symptoms include
-WBCs maculopapular rash on
dose
Miscellaneous face, neck, trunk, and
-Fever limbs and pruritus and
Antibacterials: vancomycin Dosage adjustment is hypotension caused by
required for renal histamine release. Stop
Glycopeptides Monitor actual site
impairment infusion and contact
of infection for
provider. Prepare to
improvement
Monitor trough levels administer
diphenhydramine 50mg IV
Monitor and report or PO. Monitor BP
IV should be
trough levels for closely; IV fluids and/or
administered in a
targeted dosing vasopressors may be
diluted solution over a
period of 60 minutes required if hypotensive.
or more to avoid Infusion may be restarted
rapid-infusion-related at a slower rate after rash
reactions and itching resolve