Hit and run drugs: revisited

Abstract

For a treating physician, the accurate knowledge of the pharmacokinetics of a drug aids in drug prescribing. The pharmacokinetic parameter of plasma half life (t1⁄2) is essential in deciding the dosing schedule and frequency of administration of a drug which in turn decides the compliance of the patient. Thus, it is essential for a physician to be fully aware of the dose-response and t1⁄2 relationship. However, in case of some drugs the t1⁄2 knowledge may not be helpful in deciding the dosage schedule or frequency of drug administration due to their „hit and run‟ effect. Like the pharmacokinetic aspects, the pharmacodynamics of the drug also plays an essential role in deciding the drug of choice for the specific condition. Some mechanisms of drugs affix a new pharmacodynamic action to the drug (e.g. antiplatelet action of aspirin which initially was only an analgesic) which makes the drug uniquely different from the rest of the compounds in its category. A few of drugs with such different facets of action present their unique properties owing to the „hit and run‟ effect. This short review focuses on discussing the drugs possessing this type of a pharmacokinetic and dynamic picture due to the „hit and run‟ effect and the clinical utility of such drugs.