MOD 1

Pharmacology: study of the action of drugs

Three Phases of Drug Action
1. Pharmaceutic Phase: first phase of drug action (solid and liquid form )
2. Pharmacokinetic Phase: study of how the body processes drugs
• Absorption: movement of a drug into the bloodstream
a. Passive absorption: does not require energy to move across the membrane
b. Active absorption: requires energy for active absorption
c. Pinocytosis: cells carry drugs by engulfing the drug particles
Factors Affecting Absorption
° Surface area
° Solubility
° Contact time
° Circulation
° Drug form & concentration
° Bioavailability
° Route of administration
° Ionization
Drug Absorption (Fastest → Slowest)
1. Liquids solutions (Elixirs, Syrups)
2. Suspension
3. Powders
4. Capsules
5. Tablets
6. Coated tablets
7. Enteric-coated tablets
• Distribution: transport of drugs to the site of action
Factors Affecting Distribution
° Perfusion Rate
° Permeability of Membranes
° Protein binding
° Placenta
° Tissue Localization
° Blood Brain Barrier
• Metabolism: breaking down the drug
• Excretion: process where drugs are removed from the body
3. Pharmacodynamic Phase: study of the mechanism of drug action on living tissue
Effects of Drugs (Therapeutic / Desired effect)
a) Curative
b) Chemotherapeutic
c) Substitutive
d) Supportive
e) Restorative
Chemical Interaction
° Synergistic Effect: effect of drug is higher than the sum of their individual effects
° Additive Effect: summation of effects of drugs taken concurrently
° Potentiating Effect: effect of drug is enhanced by another drug
° Antagonistic Effect: one drug cancels the effects of another
Terms
Additives: alter the location of disintegration of drugs
Adverse Drug Reaction: unwanted reaction experienced following the administration of a drug
Adverse event: harm that occurs while a patient is taking a drug
Allergy: exaggerated adverse reaction to drug
Biotransformation: body changes the chemical structure of a drug to another form
Biliary excretion (bile & feces): drugs that may be reabsorbed when passing through the intestines from the
liver
Circadian Rhythms: rate of drug absorption, hepatic clearance, half-life and duration of action, have shown
to differ depending upon the time of day a drug is administered
Clearance of drugs: elimination of drugs from circulation by all routes (Renal and Hepatic Clearance)
Disintegration: breakdown of tablet into smaller particles
Dissolution: dissolving of the smaller particles in the GI fluid before absorption
Dissolution time: time it takes for the drug to dissolve
Diffusion: movement from higher concentration to lower concentration
Drug toxicity: adverse effects of a drug that occur because the dose has risen above the therapeutic range
Drug abuse: misuse of therapeutic drugs
Duration of action: time a particular drug is active
Enteric coating: allows a drug to dissolve only in an alkaline environment
Effects of Gender and Age: elimination of the drug from the body is directly influenced by age
Efficacy: max effect that a given drug will produce
Pharmacogenetics: hereditary influences on drug responses
Plasma Half-Life: time it takes for the concentration of the drug to be reduced by 50%
Potency: amount of a given drug that is required to produce a given effect
Sustained release drugs: allow drugs to be released slowly over time
Side-effect: any effect caused by a drug
Toxicity: capacity of a drug to do damage in the body
Therapeutic index: determine how close a toxic dose is to an effective one
Therapeutic window: range of plasma concentration between the Minimum Effective Concentration (MEC)
and the Minimum Toxic Concentration (MTC)
Volume of Distribution (Vd): degree of distribution of a drug into various body tissue
Metabolite: a more water soluble compound of drug (liver)
Intestines, sweat, saliva and breast milk: constitute minor routes of drug excretion
Kidneys: major organs of excretion
Lungs: excrete gaseous drugs
Onset of action : time it takes for a medicine to start to work
First Pass Phenomenon : drugs are first absorbed through the small intestine then arrive at the liver via the
portal circulation

MOD 2

Rights of Drug Administration

° Right client: needs to be ensured by checking the wrist band, and by checking a second piece of
identification
° Right drug: client receives the drug that was prescribed by a physician (MD), dentist (DDS), podiatrist
(DPM), or an advanced practice nurse
° Right dose: dose prescribed for a particular client
° Right time: time at which the prescribed dose should be administered
° Right route: necessary for adequate absorption
Additional Rights
° Right assessment
° Right documentation
° Right evaluation
° Right to education
° Right to refuse
Components of a Drug Order
• Date and time
• Drug name
• Drug dosage
• Route
• Frequency and duration
• Any special instructions for adjusting dosage
• Physician and licensed nurse signature if TO or VO
Nurse must check the bottle against the order three different times
1. At the time of contact with bottle
2. Before pouring the drug, and
3. After pouring the drug
Four Categories of Drug Orders
1. Standing orders
2. One-time (single dose)
3. PRN
4. STAT (at once)
Routes of Drug Administration
° Nasal
° Inhalation
° Parenteral
° Oral
° Topical/Transdermal
° Ocular
° Rectal
° Otic
Medication Safety Tips
1. Check on antidotes
2. Label on properly
3. Avoid distractions
4. Report
5. Know your Rs
6. Always ask
7. Stay updated
Measuring System
1. Metric System: decimal system based on the power of ten
The basic unit of measurement are:
a. Gram – weight
b. Liter – volume
c. Meter – for linear measurements or length
2. Apothecary System
3. Household System
Drug Calculation Methods
• Tablet Dosage Calculation: used to calculate the number of tablets (Required Dose ÷ Stock Dose)
• Liquid Dosage Calculation: used to calculate the amount of medication in solution
• Intravenous Fluid Calculation: must be given at a specific rate, neither too fast nor too slow
Terms
Medication Reconciliation: involves creating a complete list of medications your patient is receiving
Sublingual Intra-nasal Parenteral Oral Transdermal
Tablets Solution Solution Suspension Powder
Lozenges Inhalation Emulsion Elixir Pastes
Sprays Suspension Solution Plaster
Emulsions
Magmas
Cachets
Gels
Intra-cochlear Vaginal Intra-respiratory Conjunctival
Solution Douches Aerosol Ointment
Ointment Creams
Suspension Ointment
Tablets

Rectal Urethral
Enemas Suppositories
Ointment
 MOD 3

Antimicrobial
° Biocides (Disinfectant)
° Antiseptic
° Anti-Infective (Antibacterial & Antimycobacteria, Antiviral, Antifungal, Antiprotozoal, Anthelmintics)
Goal of Anti-Infective Therapy: reduce the population of the invading organism
History of Anti-Infective Therapy
° 1910: Paul Ehrlich developed a synthetic chemical effective against infection-causing cells
° 1928: Alexander Fleming discovered penicillin in a mold sample
° 1935: the sulfonamides were introduced
Anti-Infective Activity
° Narrow Spectrum of Activity: effective against to few microorganisms with a very specific metabolic
pathway
° Broad Spectrum of Activity: use in treating a wide variety of infections
Factors Affecting Prescribing Anti-infective Agents
° Identification of the correct pathogen
° Selection of the right drug
Adverse Reactions to Anti-infective Therapy
° Kidney damage
° Neurotoxicity
° Gastrointestinal (GI) tract toxicity
° Hypersensitivity reactions
° Superinfections
Prophylaxis of Anti-infective Agents
° People traveling to areas where malaria is endemic
° Patients who are undergoing gastrointestinal surgery
° Patients with known cardiac valve disease
Classification of Bacteria
° Gram-positive: the cell wall retains a stain with alcohol
° Gram-negative: the cell wall loses a stain by alcohol
° Aerobic: depend on oxygen for survival
° Anaerobic: do not use oxygen
Types of Antibacterial
° Bactericidal: agent that kills bacteria
° Bacteriostatic: agent that prevents bacterial growth
Signs of Infection
° Fever
° Lethargy
° Slow-wave sleep induction
° Classic signs of inflammation (redness, swelling, heat, and pain)
Goal of Antibiotic Therapy: decrease the population of the invading bacteria to a point where the human
immune system can deal with the invaders
First Line Drugs for Tuberculosis
° Rifampin
Second Line Drugs for Tuberculosis
° Capreomycin
° Respiratory Quinolones
° Ethionamide
° Cycloserine
° 4-Aminosalicylic acid
Drugs for Leprosy
° Clopazimine
° Dapsone
Terms
Antiseptic: chemical substance that kills microorganisms on organic tissue
Anti-infective: medicines that prevent infections
Antibiotic: chemical substance produced by a microorganism to kill another microorganism
Antibacterial: substance that stops bacteria from growing and causing disease
Acquired Resistance: microorganisms that were once sensitive to the particular drug
Biocides: chemical substance intended to control any harmful organism
Bacteria: protects the cell from osmotic rupture
Culture: sample of the bacteria to be grown in a laboratory
Culture: identification of pathogen
Prophylaxis: used to prevent an infection before it occurs
Pathogens: organisms that can cause disease
Selective toxicity: ability to affect certain proteins that are used by the infecting organism
Sensitivity testing: evaluation of bacteria obtained in a culture
Spectrum: range of bacteria against which an antibiotic is effective
Superinfection: infections that occur when opportunistic pathogens have the opportunity to invade tissues
Disinfectant: chemical substance used to kill microorganisms on inanimate objects
Immune response: complex process involving chemical mediators, leukocytes, lymphocytes, antibodies,
enzymes and chemicals
Natural Resistance: many microorganisms that do not act on a specific system are not affected by the
particular drug
 MOD 6

Cancer: diseases which involves cells that spreads to other parts of the body
Types of Cancer
• Carcinoma: cancer in the body tissue that covers other organs, glands, or body structures
• Sarcoma: cancer that forms in the bones and soft tissues
• Leukemia: cancer of the blood cells that begins in the bone marrow
• Lymphoma and myeloma: cancer of immune system
• Melanoma: cancer that arise in the cells that make pigment in the skin
Antineoplastic Agents: drugs used to kill altered human cells
Neoplasm Cancer—Mechanisms of Growth
a. Anaplasia: cancerous cells lose cellular organization
b. Autonomy: cancerous cells grow without the homeostatic restrictions
c. Metastasis: cancer cells that travel to develop new tumors in other areas of the body
d. Angiogenesis: abnormal cells release enzymes to generate blood vessels
Possible Causes of Cancer (VCLEGS)
• Viral infection
• Constant irritation and cells turnover
• Lifestyle factors
• Environmental factors
• Genetic predisposition
• Stress
Classification of Tumors
• Solid tumors: may originate in any body organ (carcinoma: epithelial and sarcoma: mesenchyma)
• Hematologic malignancies (leukemia and lymphoma which occurs in blood)
Management of Cancer: Chemotherapy (used when there is suspected spread of malignant cells)
Goal of cancer treatment is to destroy cancer cells using:
• Drug therapy
• Radiation therapy
• Surgical removal
• Stimulation of the immune system
Drug Classification
“Drugs classified by those that act on a certain phase of cell reproduction (cells cycle specific) or those that
do not reproduce (cell cycle nonspecific)”
a. Cells cycle—specific agents: act on the cell during particular phase of reproduction
• Antimetabolites: specific for the S phase
• Plant alkaloids: specific for the M phase
b. Cells cycle—nonspecific drugs: act on cells during any phase of reproduction
• Alkylating agent: drugs that prevent cell division by damaging the DNA structure
• Antitumor antibiotics: drugs that attack the DNA by slipping between the DNA strands
• Nitrosoureas: alkylating agents that attack cells during the resting phase of cell growth
c. Miscellaneous agents (Matulane): used in the chemotherapy group
d. Hormonal agents (androgens): used in therapy to affect the hormonal environment
e. Combination chemotherapy
f. Other chemotherapeutic agents: Elspar: enzyme use to treat lymphocytic leukemia Eulexin: used to
treat prostate cancer Taxol: use to treat ovarian, breast, and lung cancer
Goal of Treatment
• To cure the malignancy
• To extend the survival and improve the quality of life
• Palliation
Chemotherapeutic Administration
A. Route
• Oral route: used frequently
• Intramuscular and SQ: used infrequently
• IV: provides better absorption
• Central venous catheter infusion: for continuous infusions
• Venous Access Devices (VADs): for prolonged infusions
• Intra-arterial route: delivers agents directly to tumor
• Intraperitoneal: used for ovarian and colon cancer
• Intrapleural, intrathecal, and ventricular reservoir: less frequently used routes
B. Factors for deciding dosage and timing of drugs
• Dosage calculation
• Time lapse between doses
• Side effects of each drug
• Liver and kidney function
Side Effects
a. Skin and mucosa, protective linings of the body are damaged
b. Alopecia (hair loss) caused by rapidly dividing cells of hair follicles
c. Nausea, vomiting, and anorexia are common in clients receiving chemotherapy
d. Elimination disturbances when clients does not eat well
e. Elevated uric acid and crystal stone formation
f. Hematological disruptions
g. All hormonal agents cause fluid retention
Classification of Anti-Cancer Drugs
1. Drugs Acting on Cells