When several types of medication are taken at once, their effects can influence each other. For people on HIV treatment, it's important to know about these interactions and to talk to a doctor about them. Seemingly harmless medications, many of which can be bought at a pharmacy without a prescription, can reduce the effectiveness of HIV drugs. The threat of drug resistance developing is increased. In the worst-case scenario, the HIV treatment may stop being effective.
Taking recreational drugs such as ecstasy, cocaine or heroincan alter the effectiveness of HIV drugs or worsen the consequences of the HIV infection itself. In some cases, life-threatening drug interactions can occur.