(Last updated 3/13/2017; last reviewed 3/13/2017)
A drug interaction is a reaction between two (or more) drugs (called a drug-drug interaction) or between a drug and a food or beverage (called a drug-food interaction). An existing medical condition can make certain drugs potentially harmful (called a drug-condition interaction). For example, taking a nasal decongestant if you have high blood pressure may cause an unwanted reaction.
Medicines help us feel better and stay healthy. But drug interactions can cause problems by reducing or increasing the action of a medicine or causing adverse (unwanted) side effects.
Treatment with HIV medicines (called antiretroviral therapy or ART) helps people with HIV live longer, healthier lives. But drug interactions, especially drug-drug interactions, can complicate HIV treatment.
Drug-drug interactions between HIV medicines are common. Interactions between HIV medicines may reduce or increase the concentration of an HIV medicine in the blood. The change in concentration can make the affected HIV medicine less effective, more effective, or so strong that it causes dangerous side effects.
Drug-drug interactions between HIV medicines and other medicines are also common. For example, some HIV medicines may make hormonal birth control less effective. Women using hormonal contraceptives may need to use an additional or different method of birth control to prevent pregnancy. For more information about using birth control and HIV medicines at the same time, view the AIDSinfo HIV and Birth Control infographic.
Yes, the use of HIV medicines can lead to both drug-food interactions and drug-condition interactions.
Food or beverages can affect the absorption of some HIV medicines and increase or reduce the concentration of the medicine in the blood. Depending on the HIV medicine, the change in concentration may be helpful or harmful. Instructions for HIV medicines affected by food specify whether to take the medicine with or without food. (HIV medicines not affected by food can be taken with or without food.)
Pregnancy is a condition that can affect how the body processes HIV medicines. Because of these pregnancy-related changes, dosing of an HIV medicine may change during different stages of pregnancy. But pregnant women should always consult with their health care providers before making any changes to their HIV regimens.
You can take the following steps to avoid drug interactions:
Browse the AIDSinfo Drug Database to find information on FDA-approved and investigational HIV/AIDS-related drugs, including information on drug interactions.