BASICS IN PHARMACOLOGY

BASICS IN PHARMACOLOGY

Pharmacology can be divided into 3 sections:

1.   Pharmacokinetics: deals with the absorption, distribution, biotransformation and excretion of the drugs and its metabolites from the body.

2.   Pharmacodynamics: deals with the biochemical and physiological effect of the drug as well as its mechanism of action.

3.   Pharmacogenetics: is the study of the role of genes in determining the drug metabolism.

·  Side effects and adverse effects of the drugs:

  • Side effects are the physiological effects that are not related to the desired drug effect. They are predictable. They are unavoidable since the action of the drug may not be highly targeted and influence other organs or tissue parts.

   Therapeutic Dose:

Is the smallest amount that will elicit a response and the largest dose that can be tolerated without excessive side effects.

Therapeutic Window:

Is the gap between the dose needed to produce its effect in 50% of the population and that needed for the undesired effect.

Therapeutic Index

Estimates the margin of safety of the drug.

  •  Narrow: means a narrow margin of safety e.g. Gentamicin, digoxin
  •   Broad: means a wide margin of safety. E.g aspirin.