Basic Pharmacology, Basic Definitions about Medicine

Basic Pharmacology

1. Basic PharmacologyBasic Pharmacology
Dr. Kalim UllahDr. Kalim Ullah
Chief of Pharmacy Services, BTHChief of Pharmacy Services, BTH
PhD, M. Phil., Pharm. D, GPP (Taiwan)PhD, M. Phil., Pharm. D, GPP (Taiwan)
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2. Terminology for PatientsTerminology for Patients

Drug (medication) Drug (medication)
•Natural or
 synthetic substance which
Natural or
 synthetic substance which
(when taken into a living body) affects its (when taken into a living body) affects its
functioning or
 structure, and is used in
functioning or
 structure, and is used in
the
 diagnosis, mitigation, treatment,
the
 diagnosis, mitigation, treatment,
or
 prevention of a disease
or
 prevention of a disease
•Prescription DrugPrescription Drug
prescribed by licensed practitionerprescribed by licensed practitioner
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3. Sources of DrugsSources of Drugs
•PlantsPlants
•AnimalsAnimals
•SyntheticSynthetic
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4. Terminology (con’t)Terminology (con’t)

Non-Prescription (Over-the-Counter or Non-Prescription (Over-the-Counter or
OTC)OTC)
•safe if instructions followedsafe if instructions followed
•no prescription necessaryno prescription necessary
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5. Terminology (con’t)Terminology (con’t)

Recreational DrugRecreational Drug
•use for pleasant psychological/physical use for pleasant psychological/physical
effectseffects
•no therapeutic objectiveno therapeutic objective
•e.g. Cocaine,e.g. Cocaine,
Heroin etc.Heroin etc.
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6. 
Drug Dependence:Drug Dependence: 
is the body's
 
is the body's
physical need, or
 
physical need, or
 
addictionaddiction, to a specific , to a specific
agent.
 
agent.
 

Drug Tolerance: A state in which an Drug Tolerance: A state in which an
organism no longer respond to a drug at organism no longer respond to a drug at
the same conc. And higher dose is the same conc. And higher dose is
required to get same effectrequired to get same effect
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7. Therapeutic Index
•Effective dose (ED
50)
= dose at which 50% population shows response
•Lethal dose (LD
50) =dose at which 50% population dies
•TI = LD
50/ED
50, an indication of safety of a drug (higher is better)
ED
50
LD
50
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8. Potency
•(strength) refers to the amount of drug (usually expressed
in milligrams) needed to produce an effect, such as relief of
pain or reduction of blood pressure. For instance, if 5
milligrams of drug A relieves pain as effectively as 10
milligrams of drug B, drug A is twice as potent as drug B.
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9. Efficacy
•Maximum possible effect
relative to other agents
•Indicated by peak of D-R curve
•Full agonist = 100% efficacy
•Partial agonist = 50% efficacy
•Antagonist = 0% efficacy
•Inverse agonist = -100% efficacy
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10. Response
Hi
Lo
Time
A B
Additive Effects
A + B
The effect of two chemicals is equal to the sum of the effect of the two
chemicals taken separately, eg., aspirin and motrin.
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11. Response
Hi
Lo
Time
A B
A + B
Synergistic Effects

The effect of two chemicals taken together is greater than the sum of their
separate effect at the same doses, e.g., alcohol and other drugs
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12. Response
Hi
Lo
Time
A B
A + B
Antagonistic Effects

The effect of two chemicals taken together is less than the sum of their
separate effect at the same doses
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13. Drug Nomenclature (Names)Drug Nomenclature (Names)

Chemical Name Chemical Name
•atomic/molecular structureatomic/molecular structure

Generic Name (Generic Name (OFFICIALOFFICIAL))
•derived from chemical namederived from chemical name
•listed in US Pharmacopedia & Formularylisted in US Pharmacopedia & Formulary

Trade Name (Brand)Trade Name (Brand)
•selected by Manufacturerselected by Manufacturer
•copyrightedcopyrighted
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14. Drug Nomenclature (Names)Drug Nomenclature (Names)
Chemical Chemical
NameName
Generic NameGeneric NameTrade NameTrade Name
7-chloro-1,3-dihydro-1-7-chloro-1,3-dihydro-1-
methyl-5 phenyl 2H-1, methyl-5 phenyl 2H-1,
4-benzodiazepin 2-one4-benzodiazepin 2-one
DiazepamDiazepam ValiumValium
acetaminophenacetaminophen
ParacetamolParacetamolPanadolPanadol
acetylsalicyclicacetylsalicyclicAspirinAspirin DisprinDisprin
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15. Drug ClassificationsDrug Classifications

Pharmacologic ClassificationPharmacologic Classification
•Similar CharacteristicsSimilar Characteristics
•Similar Chemical Make upSimilar Chemical Make up
•Example: Beta Blockers e.g. Atenolol, PropranololExample: Beta Blockers e.g. Atenolol, Propranolol

Therapeutic ClassificationTherapeutic Classification
•Used for similar effectUsed for similar effect
•May not have similar chemical make upMay not have similar chemical make up
•Examples: Antihypertensives e.g. Ca-Channel Examples: Antihypertensives e.g. Ca-Channel
Blockers, Blockers, ββ-Blockers-Blockers
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16. New Drug DevelopmentNew Drug Development

FDA monitors processFDA monitors process

Animal TrialsAnimal Trials

Human Trials Human Trials
•first healthy clientsfirst healthy clients
•next small # clients with the diseasenext small # clients with the disease
•next large # of clients with diseasenext large # of clients with disease
•on going reporting of side effecton going reporting of side effect
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17. Controlled Drug RegulationsControlled Drug Regulations

Double Locked ContainerDouble Locked Container
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18. Controlled Drug RegulationsControlled Drug Regulations

2 licensed personnel count (or verify 2 licensed personnel count (or verify
any discrepancies) every shift (8 hours)any discrepancies) every shift (8 hours)

Witness to all discards Witness to all discards

Record on Control Substance Sheet all Record on Control Substance Sheet all
administrations and wastes (or administrations and wastes (or
computer records)computer records)
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19. Basic DefinitionsBasic Definitions

BioavailabilityBioavailability: : absorbed and absorbed and
becomes available at the site of action.becomes available at the site of action.

PotencyPotency: :  
the amount of drug needed
 
the amount of drug needed
to produce an effect of given intensity.to produce an effect of given intensity.

EfficacyEfficacy: potential maximum therapeutic : potential maximum therapeutic
response that a drug can produce.response that a drug can produce.

Therapeutic EffectTherapeutic Effect: : desirable and desirable and
beneficial effectbeneficial effect

Adverse EffectAdverse Effect:: harmful and undesired harmful and undesired
effecteffect
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20. 
Dose ResponseDose Response: Increase dose : Increase dose
increased effect.increased effect.

ProdrugsProdrugs: The drugs changed to active : The drugs changed to active
form after absorption into the body.e.g form after absorption into the body.e.g
Levodopa.Levodopa.

Minimum Effective Conc. (MEC)Minimum Effective Conc. (MEC): :
Minimum concentration of the drug Minimum concentration of the drug
which is required to produce response.which is required to produce response.

Maximum Toxic Conc.(MTC):Maximum Toxic Conc.(MTC):
Maximum amount of drug which can be Maximum amount of drug which can be
administered to a patient to achieve administered to a patient to achieve
maximum response.maximum response.
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21. Thanks
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