PDF EBook Of Essentials Of Medical Pharmacology By KD TRIPATHI

PDF eBook Of Essentials of Medical Pharmacology by KD TRIPATHI

Table of Contents

What Is pharmacology?

Pharmacology is the science of drugs (Greek:Pharmacon-drug; logos discourse in).

In a broad sense, it deals with interaction of exo genously administered chemical molecules with living systems, or any single chemical substance which can produce a biological response is a ‘drug’.

It encompasses all aspects of knowledge about drugs, but most importantly those that are relevant to effective and safe use for medicinal purposes.

Pharmacology as an experimental science was ushered by Rudolf Buchheim who founded the first institute of pharmacology in 1847 in Germany.

In the later part of the 19th century, Oswald Schmiedeberg, regarded as the “father of pharmacology”, together with his many disciples like J Langley, T Frazer, P Ehrlich, AJ Clark, JJ Abel propounded some of the fundamental concepts in pharmacology.

Since then drugs have been purified, chemically characterized and a vast variety of highly potent and selective new drugs have been developed.

The two main divisions of pharmacology are :

(A). Pharmacodynamics and
(B). Pharmacokinetics.

Pharmacodynamics :

(Greek: dynamis—power) — What the drug does to the body.

This includes physiological and biochemical effects of drugs and their mechanism of action at organ system/subcellular macromolecular levels,

e.g.
Adrenaline → interaction with adrenoceptors → G-protein mediated stimulation of cell membrane bound adenylyl cyclase → increased intracellular cyclic 3´,5´AMP → cardiac stimulation, hepatic glycogenolysis and hyperglycaemia, etc.

Pharmacokinetics :

(Greek: Kinesis—movement)—What the body does to the drug.

This refers to movement of the drug in and alteration of the drug by the body; includes absorption, distribution, binding/localization/storage, bio transformation and excretion of the drug.

Some other important aspects of pharmacology are :

Pharmacotherapeutics :</strong pharmacological information together with knowledge of the disease for its prevention, mitigation or cure.

Clinical pharmacology :
It is the scientific study of drugs (both old and new) in man.

Chemotherapy :
It is the treatment of systemic infection/malignancy with specific drugs that have selective toxicity for the infecting organism/malignant cell with no/minimal effects on the host
cells.

Pharmacy :
It is the art and science of compounding and dispensing drugs or preparing suitable dosage forms for administration of drugs to man or animals.

Toxicology :
It is the study of poisonous effect of drugs and other chemicals (household, environmental pollutant, industrial, agricultural, homicidal) with emphasis on detection, prevention and treatment of poisonings.