This document discusses principles of pharmacology relevant for nursing students. It covers key topics like the roles of nurses in medication administration, pharmacokinetics including drug absorption, distribution, metabolism and excretion. It also describes various drug formulations and routes of administration such as oral, parenteral, topical etc. Important abbreviations used in prescriptions are defined. Guidelines for pediatric dosing using rules like Young's rule and Clark's rule are also mentioned.

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2.  Medications are substances prescribed by the client’s
prescribing practitioner to help in the treatment,
relief, or cure of the cause of the client’s health
alterations or in the prevention of such alterations.
Nurses play an essential role in the administration of,
education about, and evaluation of the effectiveness
of prescribed medications.

3.  Medication administration requires specialized
knowledge, judgment, and nursing skill based on the
principles of pharmacology. The focus of this lecture
is to assist the nursing student in applying principles
of pharmacology and in acquiring skills in the safe
administration of medications.

4.  Pharmacokinetics refers to the study of the
absorption, distribution, metabolism, and
excretion of drugs to determine the relationship
between the dose of a drug and the drug’s
concentration in blood and biological fluids.

5.  The degree and rate of absorption, or passage of a
drug from the site of administration into the
bloodstream, depend on several factors such as the
drug’s physicochemical effects, its dosage form, its
route of administration, its interactions with other
substances in the digestive system and patient's
various characteristics such as age and weight

6.  Oral preparations, such as tablets and capsules, must
first disintegrate into smaller particles for gastric
juices to dissolve and prepare the drug for
absorption in the small intestines.
 Drugs administered intramuscularly are absorbed
through the muscle into the bloodstream

7.  Suppositories are absorbed through the mucous membranes
into the blood.
 Intravenous drugs are immediately bioavailable because of
their direct injection into the blood to produce a drug effect
 Sublingual medications are absorbed more quickly than
are subcutaneous injections.

8.  Distribution refers to the movement of drugs
from the blood into various body fluids and
tissues. The rate at which the drug reaches the
specific site of action is affected by blood flow,
cell membrane permeability, and the protein
binding capacity of the medication.

9.  The process of metabolism (also known as
biotransformation) refers to the physical and
chemical processing of the drug. In metabolism, the
drug is inactivated and changed into a water-soluble
compound that can be excreted by the body. The
liver is the primary source of biotransformation.

10.  Excretion is the process in which drugs are
eliminated from the body. Factors that affect the
kidneys’ ability to excrete drugs include maturity of
the kidneys, circulation, and disease. As kidney
function decreases, there can be an accumulation of
drugs, which can result in toxicity

11.  Drugs are available in many forms for
administration by a specific route such as oral
route or parenteral route. The nurse should be
aware of the various drug forms and how they are
administered. Certain drug preparations require
special consideration regarding administration.

12.  Drugs prepared for administration by one route should not be
substituted by other drug forms. For example, when a client has
difficulty swallowing a large tablet or capsule, the nurse should
not administer an oral solution or elixir of the same drug
without first consulting the prescribing practitioner because a
liquid may be more easily and completely absorbed, producing
a higher blood level than a tablet.

13.  ORAL ROUTE - Most drugs are administered by the oral route
because it is the safest, most convenient, and least expensive
method. The disadvantage of the oral route is that it is slower
acting than the other routes. Oral route drug forms includes-
 • Tablets: compressed or molded substances to be swallowed
whole, chewed before swallowing, or placed in the buccal
pocket or under the tongue (sublingual)
 •

14.  Capsules: substances encased in either a hard or a soft soluble
container or gelatin shell that dissolves in the stomach.
 Caplets: gelatin-coated tablets that dissolve in the stomach
 Powder and granules: finely ground substances.
 Troches, lozenges, and pastilles: similar preparations of drugs
designed to dissolve in the mouth

15.  Enteric-coated tablets : coated tablets that dissolve in the
intestines.
 Time-release capsules: encased substances that are further
enclosed in smaller casings that deliver a drug dose over an
extended period of time
 Sustained-release: compounded substances designed to release
a drug slowly to maintain a steady blood medication level

16.  Syrup: it is make to change the taste of medicines. it is a
thick sweet liquid, often made by adding boiling sugar and
water or fruit juice.
 Elixirs: are sweetened hydro-alcoholic (water and alcohol)
liquids for oral use. Typically, alcohol and water are used as
solvents when the drug will not dissolve in water alone.

17.  PARENTERAL ROUTE - parenteral means introduction of a
medication by any route other than the oral-gastrointestinal
route. However, medical usage of this term refers to injecting
medication into body tissue. It includes – Intradermal,
subcutaneous, intramuscular, intravenous, intrathecal or
intraspinal, intracardiac, intrapleural, intra-arterial, and intra-
articular injections. Preparation includes ampules, single dose
vials and multi-dose vials


18.  TROPICAL ROUTE - Most topical drugs are given to deliver a
drug at, or immediately beneath, the point of application.
Although a large number of topical drugs are applied to the
skin, other topical drugs include eye, nose and throat, ear,
rectal, and vaginal preparations. Tropical drug form includes-
 Liniments: substances mixed with an alcohol, oil, or soapy
emollient that are applied to the skin

19.  Ointments: semisolid substances for topical use.
 Pastes: semisolid substances, thicker than an ointment,
that are absorbed slowly through the skin
 Transdermal patches: contain medication that is
absorbed through the skin over an extended period of
time

20.  Suppositories: gelatin substances designed to dissolve
when inserted in the rectum, urethra, or vagina.
 Inhalations: drugs or dilution of drugs administered by
the nasal or oral respiratory route for a local or systemic
effect
 Drops: Optic (eye) and otic (ear) and nasal solutions that
are instilled as drops.

21.  The prescribing practitioner determines the therapeutic drug plan and
conveys the plan to others by initiating orders or a prescription. Safe
practice dictates that a nurse follows only a written or typed order, or an
order entered into a computer system because these types of orders are
less likely to result in error or misunderstanding. Under certain
circumstances, such as in an emergency, a verbal order from the
physician may be given to a registered nurse. Which should be written
soon after the emergency normalizes.

22.  ABBREVIATION MEANING
 a.c. before meals
 p.c. after meals
 ad lib freely, as desired
 b.i.d. or b.d. two times a day
 cap capsule
 elix elixir

23.  ABBREVIATION MEANING
 h hour
 hrly hourly
 ID intradermal
 IM intramuscular
 IV intravenous
 IVPB intravenous piggyback

24.  ABBREVIATION MEANING
 per by
 PO by mouth
 prn as needed
 q every
 q2h every 2 hours
 q.i.d. four times a day

25.  ABBREVIATION MEANING
 stat immediately
 supp suppository
 susp suspension
 tab tablet
 t.i.d. three times a day
 Tr or tinct tincture

26.  ABBREVIATION MEANING
 U Units
 HS half strength/sleeping time
 TIW Thrice a week
 EOD Every other day
 aq. bull. Boiling water
 bol large single dose

27.  5 mL - 1 teaspoonful
 10 mL - 1 dessertspoonful
 15 mL - 1 tablespoonful
 30 mL - 1 ounce
 60 mL - 1 wineglassful
 120 - 1 teacupful

28.  1 mg = 1/60 grain
 4 mg = 1/15 grain
 10 mg = 1/6 grain
 15 mg = 1/4 grain
 30 mg = 1/2 grain
 60 mg = 1 grain
 1000 g (1 kg) = 2.2 pounds (lbs)

29.  Several rules have been devised to calculate infants’ and
children’s dosages (e.g., Young’s rule, Clark’s rule etc.) but
these rules give only approximate dosages. Regardless of the
method used in calculating pediatric drug dosages, the
nurse should realize that dosages are approximate and
often need adjustment based on the child’s response

30.  Young’s rule-

 If adult dose is 500 mg than a dose for 8 year old child is

31.  clarks’s rule-

 If adult dose is 500 mg than a dose for a child having 60 lbs
weight

32. By – SURESH KUMAR ( Nursing Tutor )