When choosing medicines, your doctor will think about:
- How well the medicines reduce viral load.
- How likely it is that the virus will become resistant to a certain type of medicine.
- The cost of medicines.
- Medicine side effects and your willingness to live with them.
Medicines for HIV may have unpleasant side effects. They may sometimes make you feel worse than you did before you started taking them. Talk to your doctor about your side effects. He or she may be able to adjust your medicines or prescribe a different one.
You may be able to take several medicines combined into one pill. This reduces the number of pills you have to take each day.
- Nucleoside/nucleotide reverse transcriptase inhibitors, such as abacavir, emtricitabine, and tenofovir.
- Nonnucleoside reverse transcriptase inhibitors (NNRTIs), such as efavirenz, etravirine, and nevirapine.
- Protease inhibitors (PIs), such as atazanavir, darunavir, and ritonavir.
- Entry inhibitors, such as enfuvirtide and maraviroc.
- Integrase inhibitors, such as dolutegravir and raltegravir.
Resistance to HIV medicines can occur when:
- There is a change in the way your body absorbs the medicine.
- There are interactions between two or more medicines you are taking.
- The virus changes and no longer responds to the medicines you are taking.
- You have been infected with a drug-resistant strain of the virus.
- You have not taken your medicines as prescribed by your doctor.
Using antiretroviral therapy (ART) reduces your risk of developing resistance to HIV medicines.
If your viral load doesn't drop as expected, or if your CD4+ cell count starts to fall, your doctor will try to find out why the treatment didn't work.
There are two main reasons that treatment fails:
- The virus that causes HIV has become resistant. The medicine no longer works to control virus multiplication or protect your immune system. Tests can show if resistance has occurred. You may need a different combination of medicines.
- You did not take your medicine as prescribed. If you have trouble taking the medicines exactly as prescribed, talk with your doctor.