General pharmacology

                    General Pharmacology

Introduction
The word "pharmacology" is derived from word pharmakon means drug and logus means science.

Thus, pharmacology is the science of the drugs system. It includes the knowledge of history, source, biochemical and physiological effect, mechanism of action and therapeutic uses of drug. This means, it is related with the interaction of the drug with biological system.

The general pharmacology is involves the aspects of sources of drugs, route of administration of drugs, absorption of drugs and factors affecting them, distribution, bio-transformation and excretion.

 It also involves the mechanism by which drug is acting with receptor, toxicity of drug and preclinical & clinical evaluation.


Pharmacology

(comprises of Pharmacokinetics & pharmacodynamics)

Pharmacokinetics:-

It involves movement of drug. It includes study of absorption, distribution, metabolism and excretion of drugs. The study of what happens to the drug in the body is called as pharmacokinetics.
example-
chlorpromazine absorbed at a faster rate than parentral route than oral. It have binding capacity with plasma and tissue protein, and it is metabolites in to the liver and excretion is takes about 15-30 hrs.

Pharmacodynamics:-

It is quantitative study of biological and therapeutic effect of drug.
for ex- curare (a plant extract used by tribals as arrow poison) is non depolarizing blocker which rapidly produces muscle weakness and finally leads to paralysis.

 
Other terms

Pharmacotherapeutics:- It is branch of medicine concerned with the cure of diseases or relief of symptoms and includes drug treatment.

Toxicology:- science of poisons. Poisons are substances that cause harmful, dangerous or shows fatal symptoms in animals and human beings; many drugs in large dose acts as poisons Like, aspirin in less dose acts as anticoagulant by inhibiting thromboxane A2, useful for heart patients and in high dose causes the ulceration

Chemotherapy:- it is concerned with the effect of drug upon microorganisms and parasites, living & multiplying in living organisms. It is now also useful for treatment of cancer by targeting cancerous cells.

Pharmaco-epidermiology:- It is study of the effect of the drugs in large number of people in community.