HIV Medications

HIV medications under ART

HIV treatment with its medicines is called antiretroviral therapy (ART). People on ART take a combination of HIV medicines (called an HIV regimen) every day. A person’s initial HIV regimen generally includes three HIV medicines from at least two different drug classes. ART can’t cure HIV, but HIV medicines help people with HIV live longer healthier lives. HIV medicines also reduce the risk of HIV transmission. Talk to your doctor about all of these options. With your help, your doctor can determine the best medications for you. It is vital to take them exactly as prescribed to maintain success and to help to prevent the virus from becoming resistant to the medicines. These medicines are usually taken for life.

With the advent of highly active antiretroviral therapy (HAART), HIV infection is now manageable as a chronic disease in patients who have access to medication and who achieve durable virologic suppression.

HAART provides effective treatment options for treatment-naive and treatment-experienced patients. Six classes of antiretroviral agents currently exist, as follows:

• Nucleoside reverse transcriptase inhibitors (NRTIs) NRTIs block reverse transcriptase, an enzyme HIV needs to make copies of itself. Examples include abacavir, didanosine, emtricitabine, lamivudine, stavudine and tenofovir.
• Non-nucleoside reverse transcriptase inhibitors (NNRTIs) NNRTIs bind to and later alter reverse transcriptase, an enzyme HIV needs to make copies of itself. Examples include efavirenz, etravirine, nevirapine and rilpivirine.
• Protease inhibitors (PIs) PIs block HIV protease, an enzyme HIV needs to make copies of itself. Examples include atazanavir, darunavir, fosamprenavir, indinavir, lopinavir, ritonavir, saquinavir and tipranavir.
• Integrase inhibitors (INSTIs) Integrase inhibitors block HIV integrase, an enzyme HIV needs to make copies of itself. Raltegravir is an example.
• Fusion inhibitors (FIs) Fusion inhibitors block HIV from entering the CD4 cells of the immune system. Enfuvirtide is an example.
• Chemokine receptor antagonists (CCR5 antagonists) HIV-1 most commonly uses the chemokine receptors CCR5 and/or CXCR4 as co-receptors to enter target immunological cells. Maraviroc is an example.
• There is also a medicine called cobicistat which increases the action of antiretrovirals but does not have any effect on the virus itself.

Each class targets a different step in the viral life cycle as the virus infects a CD4+ T lymphocyte or other target cell. The use of these agents in clinical practice is largely dictated by their ease or complexity of use, side-effect profile, efficacy based on clinical evidence, practice guidelines and doctor preference.

Some important considerations are:

• Adherence – taking your medicines exactly as prescribed.
• Dietary restrictions.
• Regular blood tests.
• Taking other medicines.

What to do if you miss a dose?

If you forget to take a dose, take your medicines as soon as you remember. However, if you remember just as you are about to take your next dose, do not take two doses at the same time to make up for the missed dose. If in doubt, speak with your pharmacist or doctor. If you are regularly forgetting to take your medicine, talk to your doctor or pharmacist, there may be other combination medicines that are more suitable for you.