PHARMACOLOGY

 PLACEBO ::

In medical term placebo means dummy medication it is a pharmacologically inert substance e.g. lactose that resembles the actual medicament in physical properties like size shape colour smell and taste in clinical trials it acts as the unknown control and is useful for the following ::

(a) To distinguish the pharmacodynamic effect of the drug from the psychological factors such as softness in medication increased interest of the physician such as frequent visits mode of approach his personality etc affecting the patient 

(b) To distinguish real drug effect from the fluctuations in the illness that follow in course of time and other extraneous factors .

(c) To avoid false negative conclusions 

Careful observations are made during the acute and sub-acute administration of the drug to determine the therapeutic index dose and adverse reactions 

    Some phase II trials are designed as case sseries demonstrating safety and efficacy in a selected group of patients Other phase II trials are designed as randomized clinical trials complete with a treatment arm and a comparison arm Randomized phase II trials have far fewer patients than randomized phase III trials