Pharmacology
Science of drug which deals with interaction of exogenously administered chemical molecules with living system.
Pharmacodynamics–
(What the drug does to the body)
Physiological and bio-chemical effect of drugʻand their mechanism of action at macro molecular or sub cellular or organ system level
Pharmacokinetics –
(What the body does to the drug)
Movement of the drụg and alteration of the drug by the body. It includes absorption, bio transformation and excretion of the drug
Drug –
(Drogue = dry herb)
A substance which can modify or explore the physiological system (pathological state for the benefits of recipient.
Pharmacotherapeutics –
Application of pharmacodynamic information together with knowledge of the diseases.
Clinical pharmacology –
Scientific study of the drug in man. It includes pharmacodynamics
Clinical pharmacology –
Scientific study of the drug in man.. It includes pharmacodynamics and pharmacokinetic investigation.
Chemotherapy –
Treatment of systemic infection/malignancy with specific drug that have selective toxicity for the organism or malignant cells with no or minimal effect on the host cells.
Absorption –
Movement of drug from its side of administration into the circulation.
Bio-availability :-
It is the fraction of administered dose of a drug that reaches the systemic circulation in the unchanged form.
Bio-transformation –
Chemical alteration of the drug in the body. .
First order kinetics –
– Rate of elimination § concentration
– clearance constant
Zero order kinetics
– Clearance §1/concentration
– Rate of elimination = constant
Plasma –
The plasma half life of a drug is the time taken for its plasma concentration to be reduced to half of its original value.
Plateau Principle –
When constant dose of A drug is repeated before the expiry of 4 tys. It should achieve the higher peak concentration.
Affinity –
Ability of the drug to combine with the receptor
Efficacy –
(Intrinsic Activity IA)
– Ability of the drug to activate the receptor.
Agonist –
Have both (Affinity and maximum efficacy or intrinsic activity) IA = 1
Partial Agonist
– Have Affinity and submaximal Intrinsic Activity. (IA = between 0 to 1 )
Inverse Agonist –
Have Affinity but no intrinsic activity/efficacy (IA =0) Agonist – When one drug increases the action of another drugs they are said
Competitive Agonist –
Have Affinity but intrinsic activity with a minus sign (1A = 0 to -1 )
Agonist-
When one drug increases the action of another drugs they are said agonist.
Antagonist –
When one drug decrease/inhibit the action of another, they are called Antagonist .
Synergism –
When the action of one drug is increased by the other, it called synergism
Types – (2)
Additive = Effect of drug A + B = Efect of drug A + Effect of drug
B Supra additive = Effect of drug A + B > Effect of drug A + Effect of drug B
Drug Action –
Combination of the drug with its receptors resulting in a conformational change.
Drug Effect :-
It is the ultimate change in biological function brought as a consequences of drug action
Drug Potency – Amount of drug needed to produce a certain action
Drug efficacy – The maximal response that can be elicited by the drug
Dose – Appropriate amount of drug needed to produce a certain degree of response in a patient.