Therapeutic Drug Monitoring (TDM) was introduced in India in the mid and la
te 1980s and the last 10 years have seen it grow, together with the growth
of separate Clinical Pharmacology departments. The TDM service in the count
ry is broadly of two types: in large teaching hospitals where the service i
s available through departments of Clinical Pharmacology, and in the privat
e sector, where drug estimations are done by clinical biochemistry departme
nts with minimal interpretation. This article is based on literature review
and our own experiences over a 10 year period in a department of Clinical
Pharmacology. It focuses on the evolution of TDM, its problems such as lack
of funding, special aspects such as the impact of ethnic differences, nutr
itional deficiencies, quality of medicines and availability of generic prod
ucts; its utility as a research tool and its future.