Antiretroviral therapy reduces the amount of HIV in the body. When a person takes them consistently, antiretroviral drugs are very effective at limiting the impact of the virus.
Although inequities exist by region and population, advances in antiretroviral therapy have made it possible for many people with HIV to live a comparable life span to those without HIV.
This therapy helps keep the body healthy and prevent infections. Specifically, successful antiretroviral therapy prevents people from developing advanced HIV and makes it impossible to transmit the virus to others.
The Centers for Disease Control and Protection (CDC) recommend that all people with HIV take antiretroviral therapy, regardless of how long they have had the virus or their current state of health.
Antiretroviral therapy has become more potent, less toxic, and easier to use than in the past. It produces fewer and less severe side effects than before.
This article describes various antiretroviral drugs, how they work, and their possible side effects. It also provides information about beginning treatment.
HIV is a retrovirus that targets the immune system, which is the system that fights off infection and disease. The virus damages or destroys white blood cells called CD4 cells. This makes it difficult for the body to fight off illness.
Antiretroviral therapy prevents the virus from multiplying, which reduces the amount of HIV in the body. This gives the immune system a chance to produce more CD4 cells.
Although antiretroviral therapy cannot completely remove HIV from the body, it keeps the immune system strong enough to combat infections and some HIV-related cancers.
The aim of antiretroviral therapy is to reduce the amount of HIV in the blood to very low levels. Viral suppression occurs when the count reaches fewer than 200 copies of the virus per milliliter of blood.
When the viral load is so low that it is undetectable, it no longer damages the immune system, and there is no risk of transmitting the virus to others. This is known as “undetectable = untransmittable.”
In most people using antiretroviral drugs, the virus is under control within 6 months.
Antiretroviral therapy involves taking a combination of drugs each day. An HIV treatment regimen usually involves at least three different drugs from at least two different drug classes.
The following are the different categories of antiretroviral drug:
Nucleoside reverse transcriptase inhibitors (NRTIs)
NRTIs block the action of an enzyme called viral reverse transcriptase, which is necessary for HIV to replicate.
Some examples of NRTIs include:
- abacavir (Ziagen)
- emtricitabine (Emtriva)
- lamivudine (Epivir)
- stavudine (Stavudine)
- tenofovir disoproxil fumarate (Viread)
- zidovudine (Retrovir)
Non-nucleoside reverse transcriptase inhibitors (NNRTIs)
NNRTIs work similarly to NRTIs. The only difference is that they act on different sites of the enzyme.
Some examples of these antiretroviral medications include:
- doravirine (Pifeltro)
- efavirenz (Sustiva)
- etravirine (Intelence)
- nevirapine (Viramune)
- rilpivirine (Edurant)
Protease inhibitors (PIs)
PIs impede another viral enzyme, called HIV protease. HIV requires protease to replicate.
Some types of PI include:
- atazanavir (Reyataz)
- darunavir (Prezista)
- fosamprenavir (Lexiva, Telzir)
- indinavir (Crixivan)
- lopinavir/ritonavir (Kaletra)
- ritonavir (Norvir)
- saquinavir (Invirase)
- tipranavir (Aptivus)
As the name suggests, these drugs prevent the virus from entering the targeted cells.
To penetrate immune cells, HIV must fuse to the cells’ receptors, and these drugs work to stop this from happening.
People often take entry inhibitors when other treatments have not worked.
Some examples currently in use include enfuvirtide (Fuzeon) and maraviroc (Selzentry).
HIV uses a protein called integrase to send its genetic material into the cells that it targets. Integrase inhibitors block this action.
Research into these drugs is ongoing, but some types currently approved for use include dolutegravir (Tivicay) and raltegravir (Isentress).
Antiretroviral drugs can have adverse effects. Most are manageable, but some can be serious. Newer drugs tend to cause fewer and less severe side effects.
The benefits of taking HIV medications typically outweigh the side effects. These treatments can help people live long, healthy lives with reduced risks of HIV-related complications and transmission.
The potential side effects vary depending on the types of medication a person uses. Also, the same medication can have different side effects in different people.
Some side effects from antiretroviral therapy, such as nausea or fatigue, may last only a few days or weeks. Other side effects, such as high cholesterol, may not appear for a few months or years.
Some other possible side effects of antiretroviral therapy include:
If someone experiences severe side effects or side effects that do not go away, they can talk to their healthcare provider about changing dosages or drug combinations to find the one that works best for them.
It is important to avoid stopping medication without talking to a healthcare provider first, as breaks in therapy can allow the virus to multiply rapidly, which increases the person’s risk of getting sick.
Some long-term side effects may include:
- heart disease
- kidney damage
- liver damage
- nerve damage
- weak bones, or osteoporosis
- higher levels of fat in the blood
Side effects that indicate a more serious complication and may require urgent care include:
- extreme fatigue
- persistent vomiting
- a rash
People who experience swelling of the face, throat, or tongue require emergency treatment. If this occurs, a person should call an ambulance or go to the nearest emergency room.
A healthcare provider can give advice and other forms of support to people experiencing side effects from HIV treatment. If the symptoms are severe or ongoing, they may recommend alternative medications.
It helps for people to discuss their lifestyle, needs, preferences, and current health status with their healthcare provider, who can take these into account when prescribing a treatment plan.
Antiretroviral drugs can interact with other substances, including:
- other medications
- herbal products
To avoid interactions, people should discuss all current medications and supplements with their healthcare provider, as these can influence how HIV medications work. In some cases, they can cause adverse reactions.
Some HIV drugs may also make hormonal birth control less effective. Therefore, people who use hormonal birth control may need to use a different method to prevent pregnancy.
There is no evidence to suggest that antiretroviral therapy interferes with hormonal therapy.
The CDC recommend that all people with HIV take antiretroviral therapy, regardless of how long they have had the virus or their current health status.
This includes the following groups:
- people in the early stages of HIV
- people who are pregnant or breastfeeding
- people with stage 3 HIV
- people with HIV-related infections or cancers
Ideally, a person should begin antiretroviral therapy on the day they receive a diagnosis of HIV, or as soon as possible after this. This gives people the best chance of reducing their viral load and risk of complications.
If a person does not receive effective treatment, the virus typically develops into the most advanced stage, stage 3 HIV, within 10 years. At this stage, the immune system is badly damaged, which can lead to opportunistic infections or certain types of cancer.
Research tends to suggest that receiving prompt treatment reduces the risk of transmission, disease progression, and complications.
However, it can be challenging to follow a daily treatment plan consistently for many reasons. These include:
- access to and affordability of medications
- stigma and discrimination in the healthcare system
- mental health and substance use issues
- pill fear or pill fatigue
If a person is having trouble following their treatment regimen consistently, it is best that they talk to their healthcare provider as soon as possible to work out a plan to stay healthy.
HIV.gov provides information about covering the costs of HIV treatment and tips for following an antiretroviral therapy regimen.
Antiretroviral drugs are effective treatments for HIV. Organizations around the world recommend that everyone with HIV begins this type of therapy as soon as possible after receiving their diagnosis.
These drugs can also reduce the risk of HIV-related complications, stop the virus from progressing, and prevent transmission to others.
In addition, antiretroviral medications increase a person’s quality of life and life expectancy.
Some people may experience side effects. However, these may go away after a few weeks of treatment. There are several classes of antiretroviral drug, and if one causes side effects, another may not.
A healthcare provider can offer information and guidance about the treatment options for HIV.