BENHA UNIVERSITY, CREDIT HOURS SYSTEM
PHARMACOLOGY, GENERAL (PHA311)
FOR STUDENTS ENROLLED IN PHARMACOLOGY PROGRAMS
GENERAL PHARMACOLOGY
EASY, SIMPLE, CONCISE, UNDERSTOOD
TABLE OF CONTENTS
# Topic
1 General Introduction
2 Posology: The dose & The dosage
3 Drug administration: Drug delivery to the body
4 Pharmacokinetics: Drug absorption
5 Bioavailability
6 Pharmacokinetics: Drug distribution
7 Pharmacokinetics: Drug biotransformation
8 Pharmacokinetics: Microsomal and nonmicrosomal enzymes
9 Pharmacokinetics: Drug elimination
10 Methods of prolonging drug action
11 Drug residues
12 Pharmacodynamics: Drug actions & mechanisms of actions
13 Pharmacodynamics: Dose-Response relationship analysis
14 Pharmacodynamics: Drug interactions & abnormal reactions.
General Pharmacology Surviving Revision
,BENHA UNIVERSITY, CREDIT HOURS SYSTEM
PHARMACOLOGY, GENERAL (PHA311)
FOR STUDENTS ENROLLED IN PHARMACOLOGY PROGRAMS
INTRODUCTION TO PHARMACOLOGY
Pharmacology is the science of drugs and their use as medicines. It includes knowledge about their sources,
physical and chemical properties, actions and uses, toxic effects as well as their fate in the body.
The drug is defined as any substance that can modify (increase or decrease) the function of living cells
when applied to or given to the living organism. A drug does not create a new function for a living system,
but it is usually hoped to normalize an altered function or abnormality.
Science of drugs includes:
1- Pharmacodynamics: which is the study that deals with the actions of the drugs on the body function
and their mechanisms; (What the drug could do to the body).
2- Pharmacokinetics: which is the study that deals with the different processes happening to a drug in
the body after its administration including absorption, distribution, biotransformation (metabolism)
and excretion; (What the body could do to the drug).
3- Clinical pharmacology: in which the appropriate pharmacodynamic, pharmacometric and
pharmacokinetic studies are repeated in healthy and diseased domesticated target species to assess
the possible alterations of the drug behavior in case of disease.
4- Pharmacotherapeutics: which is the study of the clinical use of drugs in treatment and prevention
of diseases; it usually includes indications, precautions and contraindications of the drug.
5- Chemotherapy: which is the study that deals with the treatment of infectious diseases caused by
bacteria, fungi, parasites as well as cancer by use of chemicals or drugs.
6- Drug Toxicology: which is the study that deals with the effect of toxic doses of drugs including
toxic symptoms, as well as their treatment. Most of the drugs in large doses act as poisons.
7- Posology: which is the study of drug dose and dosage, which varies with the species of the animal,
the intended effect of the drug and the individual tolerance or susceptibility.
A dose is the appropriate amount of a drug to be administered at a time.
Dosage refers to determination and regulation of doses.
8- Metrology: which is the study of weights and measures.
9- Pharmacognosy: which is the science of identification of drugs; it includes the description of
sources of crude drugs, their physical and chemical characters.
General Pharmacology Surviving Revision
,BENHA UNIVERSITY, CREDIT HOURS SYSTEM
10- Pharmacy: is the preparation of drugs and their presentation as medicines. Materia medica is an
old term of pharmacology concerned with the sources, description and preparation of drugs.
OFFICIAL BOOKS OF DRUGS
Information about drugs can be obtained from one of the official standard drug books. An "Official
drug" is the drug that is listed in one of these official books.
Pharmacopoeia: is an official book containing a selected list of the widely used drugs and medicinal
preparations with descriptions of their physical properties and tests for identity, purity and potency. Each
pharmacopoeia includes a list of drugs added in this particular edition and also a list of deleted drugs might
be deleted from the pharmacopoeia because of their toxic effects and/or availability of other more suitable
compounds. Majority of nations publish their own pharmacopoeia e.g. British Pharmacopoeia (B.P), United
States Pharmacopoeia (U.S.P) and Egyptian Pharmacopoeia (E.P).
International Pharmacopoeia (I.P) is published by the World Health Organization (W.H.O).
National Formulary (NF): is published by the American Pharmaceutical Association. The selection of
drugs in the N.F is based on therapeutic merit rather than the extend use of a drug. The N.F includes many
formulae for pharmaceutical preparations like solutions, tinctures, pills, powders, etc.
British Pharmaceutical Codex (B.P.C): is the British counterpart of N.F and is published by
Pharmaceutical Society of Great Britain.
British Veterinary Codex (B.V.C): This book contains the medical substances sand preparations used in
veterinary practice. It is published by the Pharmaceutical Society of the Royal College of Veterinary
Surgeons and the British Veterinary Association.
New and Non-Official Remedies (N.N.R.) It is an annually publication of the American Medical
Association including a description of marketed drugs in an acceptable manner, and which satisfy the
standards.
General Pharmacology Surviving Revision
, BENHA UNIVERSITY, CREDIT HOURS SYSTEM
PHARMACOLOGY, GENERAL (PHA311)
FOR STUDENTS ENROLLED IN PHARMACOLOGY PROGRAMS
POSOLOGY
Def.: It is the branch of pharmacology dealing with the study of the dose and the dosage of drugs.
A dose is the proper amount of the drug given at a time to the patient.
While dosage is the regimen of the dose, taken how many times for how many days.
A dose of a newly delivered drug is determined by its administration to a number of laboratory animals
using gradually increasing doses and determining the doses which produce certain effects, including:
The minimal effective dose (EDmin): is the dose which gives a response in the lowest number of
animals.
The maximal effective dose (EDmax): is the dose which gives response in all (100%) of the animals.
The submaximal doses: are the doses lying between the minimal and the maximal doses.
The median effective dose (ED50): is the dose which gives the response in half (50%) of the animals.
Minimal lethal dose (LDmin): is the dose which causes death of the lowest number of animals.
Median lethal dose (LD50): is the dose which caused death of half (50%) of the animals.
Lethal dose: is the lowest dose which causes death of all (100%) of the animals.
Therapeutic index: it is an index for the safety of a certain drug. Its value is the ratio of the LD50 to
ED50. The greater the ratio the safer is the drug.
LD50
Therapeutic index =
ED50
Standard Margin of Safety: is the percentage by which ED99 must be increased to reach LD1.
SMS = [ (LD1 / ED99) ] - 1 × 100
FACTORS AFFECTING DRUG DOSES AND RESPONSE
Many factors can modulate the response of the subject to certain drugs and thus the dose should be
adjusted after considering these factors to obtain the most favorable response.
These factors could be classified into:
Factors related to the patient.
Factors related to the drug.
General Pharmacology Surviving Revision
PHARMACOLOGY, GENERAL (PHA311)
FOR STUDENTS ENROLLED IN PHARMACOLOGY PROGRAMS
GENERAL PHARMACOLOGY
EASY, SIMPLE, CONCISE, UNDERSTOOD
TABLE OF CONTENTS
# Topic
1 General Introduction
2 Posology: The dose & The dosage
3 Drug administration: Drug delivery to the body
4 Pharmacokinetics: Drug absorption
5 Bioavailability
6 Pharmacokinetics: Drug distribution
7 Pharmacokinetics: Drug biotransformation
8 Pharmacokinetics: Microsomal and nonmicrosomal enzymes
9 Pharmacokinetics: Drug elimination
10 Methods of prolonging drug action
11 Drug residues
12 Pharmacodynamics: Drug actions & mechanisms of actions
13 Pharmacodynamics: Dose-Response relationship analysis
14 Pharmacodynamics: Drug interactions & abnormal reactions.
General Pharmacology Surviving Revision
,BENHA UNIVERSITY, CREDIT HOURS SYSTEM
PHARMACOLOGY, GENERAL (PHA311)
FOR STUDENTS ENROLLED IN PHARMACOLOGY PROGRAMS
INTRODUCTION TO PHARMACOLOGY
Pharmacology is the science of drugs and their use as medicines. It includes knowledge about their sources,
physical and chemical properties, actions and uses, toxic effects as well as their fate in the body.
The drug is defined as any substance that can modify (increase or decrease) the function of living cells
when applied to or given to the living organism. A drug does not create a new function for a living system,
but it is usually hoped to normalize an altered function or abnormality.
Science of drugs includes:
1- Pharmacodynamics: which is the study that deals with the actions of the drugs on the body function
and their mechanisms; (What the drug could do to the body).
2- Pharmacokinetics: which is the study that deals with the different processes happening to a drug in
the body after its administration including absorption, distribution, biotransformation (metabolism)
and excretion; (What the body could do to the drug).
3- Clinical pharmacology: in which the appropriate pharmacodynamic, pharmacometric and
pharmacokinetic studies are repeated in healthy and diseased domesticated target species to assess
the possible alterations of the drug behavior in case of disease.
4- Pharmacotherapeutics: which is the study of the clinical use of drugs in treatment and prevention
of diseases; it usually includes indications, precautions and contraindications of the drug.
5- Chemotherapy: which is the study that deals with the treatment of infectious diseases caused by
bacteria, fungi, parasites as well as cancer by use of chemicals or drugs.
6- Drug Toxicology: which is the study that deals with the effect of toxic doses of drugs including
toxic symptoms, as well as their treatment. Most of the drugs in large doses act as poisons.
7- Posology: which is the study of drug dose and dosage, which varies with the species of the animal,
the intended effect of the drug and the individual tolerance or susceptibility.
A dose is the appropriate amount of a drug to be administered at a time.
Dosage refers to determination and regulation of doses.
8- Metrology: which is the study of weights and measures.
9- Pharmacognosy: which is the science of identification of drugs; it includes the description of
sources of crude drugs, their physical and chemical characters.
General Pharmacology Surviving Revision
,BENHA UNIVERSITY, CREDIT HOURS SYSTEM
10- Pharmacy: is the preparation of drugs and their presentation as medicines. Materia medica is an
old term of pharmacology concerned with the sources, description and preparation of drugs.
OFFICIAL BOOKS OF DRUGS
Information about drugs can be obtained from one of the official standard drug books. An "Official
drug" is the drug that is listed in one of these official books.
Pharmacopoeia: is an official book containing a selected list of the widely used drugs and medicinal
preparations with descriptions of their physical properties and tests for identity, purity and potency. Each
pharmacopoeia includes a list of drugs added in this particular edition and also a list of deleted drugs might
be deleted from the pharmacopoeia because of their toxic effects and/or availability of other more suitable
compounds. Majority of nations publish their own pharmacopoeia e.g. British Pharmacopoeia (B.P), United
States Pharmacopoeia (U.S.P) and Egyptian Pharmacopoeia (E.P).
International Pharmacopoeia (I.P) is published by the World Health Organization (W.H.O).
National Formulary (NF): is published by the American Pharmaceutical Association. The selection of
drugs in the N.F is based on therapeutic merit rather than the extend use of a drug. The N.F includes many
formulae for pharmaceutical preparations like solutions, tinctures, pills, powders, etc.
British Pharmaceutical Codex (B.P.C): is the British counterpart of N.F and is published by
Pharmaceutical Society of Great Britain.
British Veterinary Codex (B.V.C): This book contains the medical substances sand preparations used in
veterinary practice. It is published by the Pharmaceutical Society of the Royal College of Veterinary
Surgeons and the British Veterinary Association.
New and Non-Official Remedies (N.N.R.) It is an annually publication of the American Medical
Association including a description of marketed drugs in an acceptable manner, and which satisfy the
standards.
General Pharmacology Surviving Revision
, BENHA UNIVERSITY, CREDIT HOURS SYSTEM
PHARMACOLOGY, GENERAL (PHA311)
FOR STUDENTS ENROLLED IN PHARMACOLOGY PROGRAMS
POSOLOGY
Def.: It is the branch of pharmacology dealing with the study of the dose and the dosage of drugs.
A dose is the proper amount of the drug given at a time to the patient.
While dosage is the regimen of the dose, taken how many times for how many days.
A dose of a newly delivered drug is determined by its administration to a number of laboratory animals
using gradually increasing doses and determining the doses which produce certain effects, including:
The minimal effective dose (EDmin): is the dose which gives a response in the lowest number of
animals.
The maximal effective dose (EDmax): is the dose which gives response in all (100%) of the animals.
The submaximal doses: are the doses lying between the minimal and the maximal doses.
The median effective dose (ED50): is the dose which gives the response in half (50%) of the animals.
Minimal lethal dose (LDmin): is the dose which causes death of the lowest number of animals.
Median lethal dose (LD50): is the dose which caused death of half (50%) of the animals.
Lethal dose: is the lowest dose which causes death of all (100%) of the animals.
Therapeutic index: it is an index for the safety of a certain drug. Its value is the ratio of the LD50 to
ED50. The greater the ratio the safer is the drug.
LD50
Therapeutic index =
ED50
Standard Margin of Safety: is the percentage by which ED99 must be increased to reach LD1.
SMS = [ (LD1 / ED99) ] - 1 × 100
FACTORS AFFECTING DRUG DOSES AND RESPONSE
Many factors can modulate the response of the subject to certain drugs and thus the dose should be
adjusted after considering these factors to obtain the most favorable response.
These factors could be classified into:
Factors related to the patient.
Factors related to the drug.
General Pharmacology Surviving Revision
