Summary MOH, DHA, HAAD, PROMETRIC NOTES FOR GENERAL PHARMACOLOGY

Pharmacokinetics [What body does to the drug] It means the effect of body on the drug. It includes Absorption, Distribution, Metabolism and Elimination. -: Absorption :- •It is the movement of drug from the site of administration to the systemic circulation. •For a drug to be absorbed it should be unionized and lipophilic in nature. •[Lipophilic drugs do not require energy, whereas hydrophilic drugs require energy to move. •It has to cross several biological barriers. TYPES OF ABSORPTION -: PASSIVE DIFFUSION :- •It is the movement of drug from higher concentration to the lower concentration until it reaches equilibrium. •It is also called as Fick’s first law. •The rate diffusion of the drugs across the biological membrane is directly proportional to the concentration gradient. ACTIVE TRANSPORT SYSTEM [CARRIER MEDIATED TRANSPORT] :- •They consume energy and reach equilibrium lesser extend when compare to passive diffusion •They are structure specific •Adversely affected by certain chemicals BIOAVAILABILITY:- •It is the rate and extent of drug that reaches the systemic circulation •It is expressed in percentage •For sublingual route and intravenous routes have 100% bioavailability •The main drawback of intravenous route is ADR’s cant be withdrawn •Linezolid and Cotrimoxazole are having 100% oral bioavailability •Among narrow therapeutic index drugs vancomycin has less oral bioavailability.