Pharmacology is the study of how drugs act on living organisms and the body's response to drugs. It has two main subdivisions: pharmacokinetics, which is how the body affects drugs, and pharmacodynamics, which is how drugs affect the body. Pharmacology aims to safely and effectively treat diseases using drugs by understanding their mechanisms of action, toxicity, and interactions within the body and with other substances. Rational and proper use of drugs listed on a country's Essential Drug List is important to ensure treatments are accessible, affordable and benefit patients' health.

1. Introduction to Pharmacology
 Pharmacology is the study of the action of drugs on living
tissues or organisms and how those drugs help to diagnose,
treat, cure & prevent disease or correct pathophysiology of
living tissues or organisms.
 Pharmacology is derived from two Greek words: Pharmakon
means drug & Logos means study.
 Clinical Pharmacology is the study of drugs in humans. It
includes the pharmacokinetic & pharmacodynamic studies of
drugs in humans. It is useful for rational prescription of drugs.
 Drug is defined as an agent used for the diagnosis, mitigation,
treatment, cure or prevention of diseases in humans &
animals.

2. Pharmacology has two main subdivisions:
 Pharmacokinetics (what body does to drugs?)
Absorption
Distribution
Metabolism
Elimination
Pharmacokinetics is the study of process by which a drug
is absorbed, distributed, metabolized & eliminated by the
body.
 Pharmacodynamics (what drug does to body?)
Drug + Receptor = Effect
Pharmacodynamics is the study of interaction of drug
and receptors responsible for the action in the body.

3.  Chemotherapy: it is the treatment of systemic
infection or malignancy with the effects of drugs on
microorganisms, parasites, living & multiplying in a
living organism without or minimum effects on host
cells.
 Toxicology: it is the study of poisonous effects of drugs
or other chemicals with emphasis on detection,
prevention & treatment of poisoning.
 Bioavailability: it is the fraction of an administered
drug or other chemicals that reaches the blood stream.
When the drug is given i.v. the bioavailability is 100%.
 Pharmacotherapeutics: it is the study of the use of
drugs to treat or prevent disease. It can be preventive,
palliative or restorative.

4. Drug Nomenclature
 It is the naming of the drugs. Generally a single drug is
given 3 names. Each name is used in different area of
drug industry or clinical practice.
 Chemical Name e.g: N-(4-hydroxyphenyl)acetamide
 Generic Name e.g: Paracetamol
 Brand Name e.g: Phenocet
Chemical Name Generic
Name
Brand
Name
N-(2-[[[5[(dimethylamino)methyl]-2-
furanyl]methyl]thio]ethyl]-N’-methyl-2-
nitro-1,1-Etenediamine
Ranitidine Aciloc
N-(4-Nitro-2-
phenoxyphenyl)methanesulfonamide
Nimesulide Nims

5.  Chemical Names
 It is the name given to the molecular formula of drugs by
IUPAC or chemical body. Chemical name represents the
chemical elements present in the compound. The chemical
name is important to chemists, pharmacists or researcher who
synthesize drugs.
 Chemical name of Paracetamol is N-(4-hydroxyphenyl)acetamide.
 Generic Names
 It is the official name of the drug and accepted universally.
Generic name appears on all drug labels and listed in official
books such as Formulary, Pharmacopoeia & Physicians Desk
Reference (PDR).
 Generic name of Aciloc is Ranitidine.

6.  Brand Name
 It is the name given to a drug by the company which
manufactures drug. Each company has their own
brand name & have copyright©.
 Brand name for Ranitidine is Aciloc by Cadila.

10. Drug orders
 Routine order
It is an ongoing order
e.g:Lasix (Furosemide) 40 mg po od
 One time order
It is single dose
e.g: Demerol(pethidine)50mg+vistaril(hydroxyzine) 25mg
i.m.
 PRN
When required e.g: Advil(Ibuprofen) 600mg po PRN
 Stat
Immidiately e.g: benadryl 50 mg po stat

11. Essential Drug List (EDL)
 Essential drugs are all those drugs that satisfy the
primary health care needs of the population. EDL is
needed to ensure safety, efficacy & quality of drugs. It
ensures availability & accessibility of essential medicines
to all citizens. It promotes the rational use of drugs by
prescriber, dispenser & patient. It helps to minimize
unwanted or diverse effects of drugs. Essential drugs
should be available at all times, in adequate amounts, in
appropriate dosage forms & at affordable price.

12.  EDL concept was first initiated by WHO in 1977.
 EDL was first published in Nepal by DDA in 1986 and
now it has fifth revision in 2016.
 GON provides 70 types of medicines for communicable
and non-communicable diseases free of cost from all
district hospitals throughout the country.
 Primary Health Care centres provides 58 types of
medicines and health posts provides 35 types of
medicines to patients without any charge.

14. S.N. Generic Name Dosage Form
1.Anaesthetics Ketamine inj 50mg/ml
2.NSAIDS, DMARDS Ibuprofen tab 200mg,400mg
3.Antiallergics chlorpheniramine tab 4mg
4 Antidotes Activated charcoal Powder, slurry in sorbitol
5. Antiepileptics/Anticonvulsants Carbamazepine tab 100mg
6. Antiinfectives Albendazole tab 400mg
7.Antimigraine Ergotamine tab 1 mg
8.Antineoplastic Cisplatin Powder for inj 10 mg
9.Antiparkinson Levodopa
+ Carbidopa
tab 100mg+10mg
10.Drug affecting blood Warfarin tab 5mg

15. Rational Use Of Drugs
 Rational use of drugs ensures that patients receive
medicines appropriate to their clinical needs, in proper
doses, for adequate period of time & at affordable cost
to patients.
Five Rights of Drug Administration:
 Right patient
 Right drug
 Right dose
 Right time
 Right route

16.  Drug Categories:
 Schedule A (क)
Narcotic & Poisonous drugs are included in this category.
Prescription is required & record should be kept for such
drugs. e.g: morphine, pethidine, methotrexate,
vincristine, chlorambucil, etc
 Schedule B (ख)
 Prescription drugs are included in this category. E.g:
amoxicillin, cloxacillin, gentamicin, antirabies serum, etc
 Schedule C (ग)
Over The Counter(OTC) drugs are included in this
category. These drugs can be available to patients without
prescription. They are are categorized as safe.
e.g: Paracetamol, vitamin supplements, metronidazole,
etc

18. Route of Administration Primary Dosage Forms