PHARMACOLOGY

PHARMACOLOGY FOR NURSES;

CLINICAL Pharmacology.
 Definition of terms
• DRUG
• It is any substance that can be used to prevent, diagnose and treat diseases.
Therefore they have different sources and functions.
• PHARMACOLOGY
• It is the science of drugs and it includes the sources of drugs, the action of
drugs, the fate of drugs, the precautions taken and their side effects or toxic
effects.
• PRESCRIPTION
• It is the act of writing medicines for easy communication between the person
prescribing, the person giving out the drug, the person administering the drug
and the person taking the drug.
• PHARMACOGNOCY
• This is the science that deals with the sources of drugs.
• PHARMACODYNAMICS
• This is the action and the fate of the drugs in the human system or other system.
 Definition of terms
• POSOLOGY
• It is the dosaging of drugs [how to dosage drugs]
• TOXICOLOGY
• This refers to the toxic effects of drugs[toxicity]
• PHARMACY
• It is a place here drugs are prepared, compounded and dispensed to the
final user of the substance.
• PHAR.ACIST
• This is somebody who dispenses drugs to clients with a clear knowledge
of pharmacology, pharmacognosy, pharmacodynamics and toxicity of
drugs. She/he is a trained, licensed person who is often assisted by
pharmacy attendants.
•
• PHARMACY ATTENDANT
• Somebody with minimal training to dispense drugs as prescribed
 DEFINITION OF TERMS
• THERAPEUTIC
It is a science that deals with the reduction or cure
of disease .Therefore therapeutic action is that
action that a drug produces to treat a disease.
• PHARMACEUTICAL
The science of combining pharmacology
and mass production for supply to dispensing
units.It is also the science for producing materials
for the manufacture of drugs.
• SOURCES OF DRUGS
• There are three main sources of drugs:
• PLANTS
• ANIMALS
• MINERALS
• Presently synthetic drugs
• All patients receiving medication have the
right to have them administered safely,
• The nurses must assume certain
responsibilities when administering
medications and always follow the 7 rights of
medication administration:
 PATIENT’S RIGHTS ON
• The right medication
• The right patient
• The right dose
• The right route
• The right time
• The right to take or refuse the medication
• The right to information / Education
concerning medication:
 DRUG NAMES
The majority of medications today have 4 names,
namely:
• Chemical name,
• Generic name, (non proprietary)
• The trade name ( brand name or proprietary
name) and
• An official name.
-The chemical name is primarily used by chemists
and represent the chemical formulation of a drug
e.g. normal saline = NACL
 MEDICATION NUMENCLETURE
The trade name is created by the manufacturer
and is always capitalized: If the name is
registered, the trade mark symbol is found at
the upper right of the Name e.g. Valium.
Both generic and trade drugs are regulated by
law ,with respect to the amount and purity of
the drug. Only a relatively small amount of a
tablet or capsules is composed of active drug.
The remainder is made up of non medicinal
substances, which are not regulated
 DRUG NAMES CONTINUED
• The ultimate formulation of the drug may
affect the drug action. Consumer groups have
caused legislators to enact generic drug laws
in many states.
• These laws require pharmacist to fill
prescriptions with a generic form of a
prescribed drug unless the prescriber writes
‘’DAW’’ (dispense as written). Generic drugs
are often less expensive than trade drugs,
there4 the cost of medical care can be
 DRUG NAMES CONTINUED
The official name, often the generic is listed on
an official compendium, the United States
Pharmacopeia – National formulary (USP – NF).
The US food and drug administration (FDA)
selects one formulation of a drug, usually the
original of its kind, as a reference drug.
The reference drug is the standard of all other
drugs of its group the FDA will then use this
standard to test all other criteria’s.
 MEDICATION PREPARATION –
LOCAL AND SYSTEMIC
• Medications are administered to have either a
local or system effect.
• A local effect is one in which the effects of
medications are confined to one area of the
body e.g. Antiseptics, Anti inflammatory and
some powders are used locally.
MEDICATION PREPARATIONS Cont.
A systemic effect is obtained when the
medication is absorbed and delivered to the
body tissue by way of the vascular system.
Some medications although applied locally, such
as Nitroglycerin, have a systemic effect due to
their absorption through the skin.
 LOCAL MEDICATIONS
The mucus membranes lining all external body
cavity’s – the mouth, nose rectum, vagina and
urethra – are excellent surfaces of medication
release, 6l% of the large numbers of capillaries
are directly beneath the surface of the skin.
Injection of medication into joint cavities is
generally done for the purpose of reducing
inflammation in the joint, its effects are due to
the presence of the large numbers of capillaries
in the joint.
• Local medications come in many forms, ointments,
creams, powders, tinctures, aerosol, gels and lotions.
Local medication can also be obtained as fumes, pasts
and suppositories for rectal, vagina and urethra
applications. The medication can also be administered
through an enema or irrigation into the rectum. Sprays,
aerosols, gases, (including O2 and CO2 and nebulizers)
are methods of introducing local or systemic
medications. Local medications are in many different
forms (gels, pasts, and liquids) can be administered into
the surface of mucus membranes and to clean teeth or
to refresh the breath
 LOCAL MEDICATION CONT,
• Though lozenges or troches are also used
locally to produce prolong relieve of an
irritated mouth or throat, many of these
preparations are available as over the counter
drugs, you can buy without prescription.
• The Local medications are used for the
following specific effects:
• Astringents: Astringents cause vaso constriction and
tissue contraction which either decrease or dry-up
secretions, there by toughening tissues .
• Cleansing agent: they help to removed dirt, gross
secretions and debris from wherever applied.
• Anaesthetics: produce a lost of feel or sensation in
the part of the body where it is administered.
• Emollients: Emollients sooth and soften, and often
reduce dryness of the skin.
• Antibiotics /Bactericidal Agents: These are chemical
compounds either produced by or obtained from
certain living cells especially yeast and moles or
made from synthetic compounds. They are
antagonistic to other forms of life.
• Anti-inflammatory: They reduced or
counteract inflammations or inflammatory
processes.
• Fungicides: These are agents that destroy
fungi, they are local medications, which can
be water based (aqueous)or oil based
preparations. H20 based medications are
readily absorbed, oil base medication should
not be used in the nose or respiratory tract,
since the oil can be carried to the alveoli and
the patient may develop lipoid pneumonia.
 SYSTEMIC MEDICATIONS
• Systemic medications are absorbed into the
vascular system. They are carried through the
body and affect one or more tissue groups. To
give 2 examples: antibiotics administered
orally are absorbed from the small intestine
and carried to the vascular system to attack
certain bacteria found in the blood stream of a
patient with septicaemia.
• -Digitalis, a medication for the heart,
 is absorbed from the small intestine and carried
through the vascular system to the heart, where
it effects a change on the heart muscle. Systemic
medications can be administered orally,
topically, parenterally or applied to mucus
membranes.
 SYSTEMIC MEDICATIONS
Parenteral administrations refer to a medication
being introduced into the body through any
route other than the gastro- intestinal route,
such as the intradermal, subcutaneous, IM or IV
routes.
 ROUTES OF MEDICATION
ADMINISTRATION
• THE ORAL ROUTE
The oral route is the most common route of
administration, and is usually the safest, the
most economical and normally the easiest route
for administration. The choice of an oral dosage
form, over all other methods of administration
involves careful consideration of both drug and
patient’s variables
• Drug variables include; a prolonged
absorption time, which delays the onset of
action,
– Decrease drug absorption which may cause
decrease action.
– Possible gastro intestinal upsets.
• Possible interaction with food and other
medications and the possibility of a prolong
effect.
Oral medications are administered with sufficient
amount of water to ensure that they enter the
stomach; the administration of H20 with an oral
medication always enhances absorption. The action of
expectorants such as guanfanesin and Iodine products
may be enhanced by drinking 6 to 8 glasses of water
daily. Exceptions include some cough medicines that
are given for a local soothing effect of the throat.
• The oral route of administration has some disadvantages,
patients may objects to the taste of medication or the
medication may cause gastric upset, constipation or
diarrhoea.
• Some medications may harm or stain the teeth. The
medication may also be destroyed by gastro-intestinal
secretions such as bile, hydrochloric acid etc and thus fail
to effect its desired results.
• Oral medications may also be inadvertently be aspirated
by the seriously ill, old or young patients, the nurse must
know the correct time to administer oral medications,
some oral medications are best administered with food to
enhance absorption or to decrease their gastric irritation
Where as, others are given on an empty stomach, then
it may be necessary to modify the time schedule so
that medications can be administered at meal times.
Oral medications are available in 2 forms solids and
liquids. The solid forms already available include
tablets, capsules, and powders. Capsules and caplets
are often stamped or embossed with a pharmaceutical
company’s name, drug name and or an un-identified
number; tablets, capsules, and caplets may occasionally
be crushed and mixed with simple apple sources or
other medium for patients who have difficulties
swallowing or are to be administered down a feeding
tube.
These products are designed to be released
after a long period of time so as to reduce the
number of dosage a patient has to take each
day. Unlike other tablets, these type should
never be crushed, because this will destroy the
intrinsic factor. Syrups, elixirs, emulsions, gels or
magmas, tinctures aromatic waters, fluid
extracts are other forms of oral medication.
 PARENTARAL ROUTES
The parenteral route is used for medications
entering the body through any route other than
oral through the gastrointestinal system and
commonly referred to as SC, IM, IV, Intradermal
routes.
All medications entering the body in this
manner must be sterile since parenteral
medications always enter the blood stream
readily; great care is always taken when
administering them to patients. Parental
medications usually have a faster course of
• Parental medications are generally more
expensive than their oral forms because of the
greater cost of preparation .The
administration of medications through the
parenteral route often takes specialist
training. Only the physician, nurse, or other
specially trained person administers
parenteral medications.
• There are several parental routes that can be
used:
• The intradermal route, just under the surface
of skin,
• Sub cutenous route, into the sub cutenous
tissue
• Intra muscular route into the muscle tissue
• Intra veinous route , into the vein
• Some common medication dosage forms
• Parental medications are generally more expensive than their oral forms because of the

greater cost of preparation .The administration of medications through the parenteral

route often takes specialist training. Only the physician, nurse, or other specially trained

person administers parenteral medications. There are several parental routes that can be

used: The intradermal route, just under the surface of skin,

• Sub cutaneous route, into the sub cutaneous tissue

• Intra muscular route into the muscle tissue

• Intra venous route , into the vein

• Some common medication dosage forms

•
 COMPOSITION OF DRUGS

• The chemical composition of drugs often vary with the

pharmaceutical preparation.There4, there are different elements
in drugs and the composition includes,
• ELEMENTS
• BIOLOGICAL SUBSTANCE
• SYNTHETIC COMPOUND
• I ] ELEMENTS: the elements include, iodine, iron, magnesium etc.
• Ii] The biological substances are often seen in vaccines and
serums.
• Iii] The synthetic composition is often made up of organic and
inorganic compounds. Sometimes it is easy to know the
composition of drugs from the way the name is written.
 CLASSIFICATION OF DRUGS
• Usually drugs are classified according to their actions or the
system on which they function.
• By their actions, these drugs can be classified as ---Analgesics
• Antacids
• Antihelmintics
• Anticoagulants
• Anticonvulsants
• Antibiotics
• Antidiabetics
• Antidiarrheas
• Antidepresants
• Cytotoxics [Anti cancers]
• Antihistamins
 CLASSIFICATION OF DRUGS
• Anti virals
• Anti retrovirals
• ANTIPYRETICS
• Anti inflammatories
• 2 ] Coagulants
• Diuretics
• Emetics
• Anti emetics
• Anti pruritics
• Haemostatic, heamotics
• Tranquilizers and sedatives
• Antiseptics [disinfectants]
• Anti hypertensive [hypotensive]
• Expectorants
• Contraceptives
 CLASSIFICATION OF DRUGS
• CaLminatives [ gas expellants]
• Antispasmodiques
• Laxatives
• Antifungal
• Relaxants
• Stimulants
• Anti toxins
• Narcotics
• Toxoids
• VaccineS
•
 CLASSIFICATION OF DRUGS
• 3] Drugs can also be classified by systems e.g
• I] Drugs of the central nervous system
• Ii] Drugs of the alimentary system
• Iii] Drugs of the respiratory system
• Iv] Drugs of the urinary system
• V] Drugs of the cardiac and circulatory
system.
 FORMS OF DRUGS
• These are the simple forms of presentation of drugs in
utilizable forms e.g. capsules, mixtures, creams,
ointments, emulsions [fine oils], Elixirs [sweet liquids],
liniments, inhalations, linty or tinctures [
syrups],lozenges and troches. Tablets [scored, enteric
coated], pills, pastes [like ointments], passeries [
vagina], poultices [ local], suppositories, Extracts[ from
vegetables],injections[i.m, i.v, subcutaneous etc],
spirits, tinctures[ alcohol], magmas[milk], medicated
water, oils nasal drops, paints, sprays, vaccines, Special
purpose sterile solutions like glucose, dextrose, etc.
•
 ROUTES OF DRUG ADMINISTRATION
• ORAL; Most frequently used method of
administration. It is safe, economical, and
convenient. Drugs for such administration may
be in forms of powders, tablets, liquids or
capsules. Its limitations include vomiting, non
absorption, inactivation, nausea, non
compliance. Drugs that have unpleasant taste
may have to be disguised in a vehicle before
they can be taken. Liquid drugs that can stain
the teeth should be administered with a straw.
 ROUTES OF DRUG ADMINISTRATION
• SUBLINGUAL: The drug is placed under the
tongue, for it to dissolve and be absorbed. The
area under the tongue is highly vascularised,
so that the drug gets straight into the
circulation without passing through the liver.
 ROUTES OF DRUG ADMINISTRATION
• RECTAL; Either as a suppository or rectal
strips. Useful in replacing the oral route or
administration of unpleasant drugs. Some
enter the general circulation and pass through
the liver.
 ROUTES OF DRUG ADMINISTRATION
• PARENTERAL ROUTE; Used when oral and
rectal medications are not necessary.
PARENTERAL SITES OF DRUG ADM.
• INTRAMUSCULAR [DEEP INTO THE MUSCLE)
Commonest site of drug administration and
includes the gluteal, the deltoid, and vastus
lateralis [ outer aspect of the thigh muscles] ,
rapid absorption even more than the
subcutaneous tissue. Absorption takes place as
the drugs move along the muscle fibres and
disseminate. Aqueous substances are absorbed
faster than oily ones.
•
 ROUTES OF DRUG ADM.
• INTRADERMAL; superficially into the outer
layer of the skin. Sites used include the medial
surface of the arm.
•
• SUBCUTENOUS; INTO the subcutaneous
tissues, drugs here must be soluble, sterile
and not irritating to tissues. Amount injected
is usually 2mls or less, because these muscles
can not tolerate greater quantities.
 ROUTES OF DRUG ADM.
• INTRA VEINOUS; given directly into the vein or
by infusions where large volumes can be given
than other routes. Rapid results are achieved
and medications are given through this route
for various reasons e.g replacement of
electrolytes, convey drugs for quick action,
restoration of blood volumes to counteract
toxic substances/drugs consumed.
 ROUTES OF DRUG ADM.
• INHALATIONS; Volatile gaseous drugs are
absorbed by the epithelium of the respiratory
tract e.g Ventoline.
THE NURSES RESPONSIBILITY IN DRUG
ADMINISTRATION
• IN THE WARD SITUATION there are a number
of guiding principles of drug administration.
Regardless of the variation of procedures in
the different hospitals. A drug prescribed by a
physician is either written on a clients card, or
exercise book or the case notes. These remain
as permanent records to obtain information of
the client.
 RESPONSIBILITIES OF THE NURSE
• A nurse should not alter the prescription of a physician
or the prescriber. In case of an error, verify from the
physician or prescriber before the administration of the
drug.
• Any prescription administered over the phone should
be recorded in the case notes along with other
information by the authorized nurse. He/She should
indicate the name of the physician or who so ever
prescribed, indicate that the prescription is by phone
and sign his /her name. The prescriber should be made
to sign the prescription order as soon as possible on
arrival.
 RESPONSIBILITY IN DRUG
ADMINISTRATION
• Administer only drugs that have been
prescribed.
• Do not substitute one drug for another
without the order of the prescriber.
• Make sure that there is a medicine card or
exercise book note, for each drug to be
administered.
 RESPONSIBILITIES IN DRUG
PRESCRIPTION
• Read the label of the drugs three times before
taking the drug container from the shelve or
tray, before pouring the drug from its
container and before returning the drug
container to the shelve or tray.
• Do not administer a drug prepared by some
one else. Prepare the drug you have to
administer to the client yourself.
• Check to make sure that;
• You have the correct drug
• You are serving the correct client by calling him by name,
as it is on his or her case notes.
• Serve the correct dose of the drug using the clients’ case
notes or card.
• Verify the route of administration on the case notes.
• Times of drug administration should be followed strictly.
• Avoid distractions when administering drugs, keep your
mind focused on what you are doing.stay with the client
until the client has taken the drug.
• Assist the client to take the drug.
 RESPONSIBILITIES OF DRUG ADM.
• Chart the drug after administration and not
before administration. Recordings should include
the name of the drug given, the dose, the time of
administration, the frequency of administration
and the client’s reaction, or refusal to take the
medication and the signature of the nurse
administering the medication. Never return to
the container unused portions of the drug that
has been poured out but have not been
administered [mixtures].
 MATERIALS USED FOR DRUG
ADMINISTRATION
• Tea spoon ( 5mls)
• Desert spoon (10mls)
• Adults table spoon (15mls), drugs for adults
• Plastics/ Glass, graduated from its base to its
brim,1cc, 3cc to 5cc, for syrups, mixtures.
• Syringes and needles; usually graduated in
1cc, 2cc,5cc, 20cc, 50cc.
• PIPETTES and Spatulars
 ROUTES OF DRUG ADMINISTRATION

• One of the important responsibilities in

health care is that of dug administration.
Drugs are absorbed in different rates through
the different routes of administration .The rate
of absorption of a drug can be modified by
the route of administration the following
routes are used for drug administration.
 ROUTES OF DRUG ADMINISTRATION
• LOCAL; Applied topically on the skin or mucus
membrane. Such drugs produce a soothing
and antiseptic effect. Ointments and lotions
may be used for itches, also applies to
administrations of the eyes, ears, nose, throat,
respiratory tract and the vagina. Application is
by use of swaps, spraying, and instillations or
by spraying or irrigation
 SOURCES OF DRUGS

• PLANTS
• ANIMALS
• MINERALS
 COURSE CONTENT
• COURSE OUTLINE
• 1} Definitions
• 2} Sources of drugs
• 3} Forms of drugs
• 4} Classification of drugs
• 5} Materials used in drug administration
• 6} Preservation of drugs in hospital
• 7} Terminologies of drug effects
• 8} Abbreviations used in drug prescriptions
• 9} Factors that can modify drug actions
• 10} Unwanted or side effects of drugs and the responsibility of the Nurse
• 11} The responsibility of he nurse in drug administration
• 12} Medical prescription and its parts
• 13} Role of the nurse in the different routes of drug administrations [Intra-muscular, Intra-
vienous, etc}
• 14} I V Infusions and complications
• 15} Responsibilities of the nurse in the administration of drugs different classes
• 16} Blood transfusion.