INTRODUCTION

The HIV-infected patient is typically taking a number of medications - for prophylaxis and therapy of opportunistic infections, and for controlling HIV replication. This significantly increases the likelihood of drug interactions in these patients.

Drug interactions usually occur when one drug affects the manner in which another drug is absorbed, metabolized, distributed or excreted in the system. Thus, a drug could reduce the blood levels of another drug, leading to suboptimal efficacy and development of drug resistant virus. Interactions can also occur when one drug alters the effect of another drug or when two drugs have similar type of toxicities.

For example, both didanosine and zalcitabine can cause peripheral neuropathy and are not recommended for use in combination. Similarly, both zidovudine and ganciclovir may cause bone marrow toxicity.

Drug interactions may occur immediately or take weeks to develop. The result is that concomitant use of certain drugs is to be avoided or careful monitoring is recommended to avoid complications. This makes it imperative for the physician treating HIV/AIDS to be familiar with commonly occurring interactions in their patients.

This booklet published by Cipla presents a comprehensive review and a guide for the management of drug interactions in patients with HIV disease.