HIV Management

Key takeaways

• HIV treatment combines three or more antiretroviral drugs from different classes into one daily regimen, often as a single combination tablet.
• The main classes are NRTIs (abacavir, tenofovir, emtricitabine, lamivudine, zidovudine, didanosine), NNRTIs (efavirenz), integrase inhibitors (dolutegravir, raltegravir) and protease inhibitors (lopinavir, darunavir, boosted with ritonavir).
• Taking every dose on schedule, more than which specific drugs you take, decides whether the virus stays undetectable. Missed doses let it rebound and can breed resistance.
• Before starting abacavir, you need a genetic test for the HLA-B*5701 marker. Carriers can develop a severe, sometimes fatal hypersensitivity reaction, so the drug is avoided entirely in anyone who tests positive.

How antiretroviral therapy works

Each drug class blocks a different step the virus needs to copy itself. NRTIs and NNRTIs stop reverse transcriptase from turning viral RNA into DNA, integrase inhibitors stop that DNA from inserting into your cells, and protease inhibitors stop new viral particles from maturing. Combining classes attacks the virus at multiple points, driving blood virus levels down to undetectable and helping prevent resistance.

Choosing between abacavir, dolutegravir, tenofovir, efavirenz, zidovudine, darunavir and ritonavir

• Abacavir (an NRTI) requires HLA-B*5701 testing before the first dose. Skipping it risks a severe, sometimes fatal hypersensitivity reaction that is worse if the drug is restarted later.
• Dolutegravir, an integrase inhibitor, blocks viral DNA from inserting into your genome. It's dosed once daily and has a high barrier to resistance, which is why it anchors many first-line regimens.
• Tenofovir disoproxil (an NRTI) needs periodic kidney function and bone density checks, since long-term use can reduce both.
• Efavirenz (an NNRTI) is usually dosed at bedtime because it commonly causes vivid dreams, dizziness and other nervous system effects in the first weeks of treatment.
• Zidovudine, one of the first antiretrovirals developed, can suppress bone marrow function, so regular blood counts catch anemia early.
• Darunavir, a protease inhibitor, blocks the enzyme that cuts viral proteins into pieces needed to build new virus particles, usually taken with a low dose of ritonavir.
• Ritonavir is rarely used to treat HIV on its own. Instead it boosts blood levels of other protease inhibitors, such as darunavir and lopinavir, by slowing how fast the liver breaks them down.

Lamivudine, emtricitabine and didanosine are other NRTIs, blocking reverse transcriptase like abacavir and paired with a drug from a different class. Raltegravir is an integrase inhibitor like dolutegravir. Lopinavir is a protease inhibitor almost always sold pre-combined with ritonavir.

Common questions

What does "undetectable" actually mean?

It means the amount of HIV in your blood has dropped below what standard tests can measure. It is not a cure: the virus stays present in reservoirs, and stopping treatment lets it rebound within weeks.

Can I switch between different antiretroviral drugs?

Yes. Doctors adjust regimens for side effects, kidney or bone changes, drug interactions, or a simpler schedule. Switches keep at least two active drugs covering the virus at all times, which protects against resistance.

Why do I need regular blood tests during treatment?

Viral load and CD4 count show how well the regimen works, while kidney, liver and bone markers catch side effects tied to drugs like tenofovir or zidovudine.

Safety essentials

• Never start abacavir without a documented HLA-B*5701 result, and never restart abacavir after a suspected hypersensitivity reaction.
• Take every dose at the scheduled time. Inconsistent adherence is the leading cause of treatment failure and drug resistance.
• Tell your prescriber about every medication you take; several antiretrovirals interact with hormonal contraceptives and acid-reducing medicines.
• Seek urgent care for fever, rash, nausea or breathing difficulty after starting abacavir, or for unexplained severe fatigue, jaundice or breathlessness on any regimen.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.