A large no of synthetic and natural compounds behave as very effective drugs.All these compounds have a wide range of biological activities like anti-bacterial, anti-fungal, anti-cancer, anti-viral, antiinflammatory, anti-neoplastic, anti-tumorigenic, anti-HIV and so on.On the other hand, metals have played an important role in medicine for years.Many are essential in our diets in varying quantities.In addition to the metalloantibiotics, a number of drugs and potential pharmaceutical agents also contain metal-binding or metal-recognition sites, which can bind or interact with metal ions and potentially influence (increase or decrease) their bioactivities.In this review changes in drug potentiality upon interaction of metal ions with some natural and synthetic drugs have been discussed.Different metal ions which are toxic at higher concentrations are also useful for maintaining life processes at lower concentrations and are even effective in the modification of some well established drug molecules towards their better action.The alkaline earths and transition metal ions are the most thoroughly studied amongst all.INTRODUCTION: Different synthetic drugs like quinolones, fluoroquinolones, piroxicam, triazole compounds, trimethoprims, verliprides have potential applications as antimicrobial, antiinflammatory, anticancer and antipsychotic agents.These drugs are widely prescribed and used for their respective actions in human body.However, there is also over-usage of these drugs which result in their excess concentration in the body which is many times undesirable.Metal ion complexation may affect the drug activity of these compounds either in positive or negative way 1 .Humans are also exposed to different metal ions either through diet or through different environmental factors.