HIV treatment consists of drugs known as antiretroviral drugs, antiretroviral therapy or ART. In total there are more than 30 anti HIV drugs. But although there are many different drugs there are only a few combinations that are regularly used.
HIV drug combinations
There are several groups or type of antiretroviral drug which work against HIV in different ways. Doctors recommend that an HIV positive person should take a combination of drugs from at least two different groups. A single drug should never be taken on its own. A combination of drugs is most effective at controlling HIV and it stops the amount of HIV from increasing. A combination of drugs also stop the virus from developing resistance to the drugs. If the virus is resistant to a drug it means that the drug won't work.
The standard recommendation now is that HIV treatment with at least three different drugs should be provided for all people newly diagnosed with HIV.1Interim guidelines - Updated recommendations on first line and second line antiretroviral regimens and post-exposure prophylaxis and recommendations on early infecnt diagnosis of HIV, World Health Organisation (WHO), 2018, https://apps.who.int/iris/bitstream/handle/10665/277395/WHO-CDS-HIV-18.51-eng.pdf?us=1
The recovery of the immune system
Combination antiretroviral therapy also allows an HIV positive person's immune system to recover after it has been damaged by HIV. The purpose of a person's immune system is to protect the body against certain bacteria, viruses and fungi. The immune system also destroys any infectious micro-organisms that do invade the body.
Is HIV treatment a cure?
HIV treatment is not a cure. It must be taken every day or HIV will start increasing again.
When should HIV treatment be started?
It used to be recommended that antiretroviral treatment should be started when a person's CD4 count fell below a certain level. But now the World Health Organisation (WHO) recommends that everyone living with HIV should start HIV treatment as soon as possible regardless of their CD4 count.
The CD4 count is a test which measures how many CD4 cells an HIV positive person has in their blood. It effectively shows how well a person's immune system is functioning. A person's CD4 count should increase as a result of a person taking HIV treatment.
How do you know if HIV treatment is working
A viral load test is a way of checking if a person's HIV treatment is working. It is a way of measuring the amount of HIV there is in a cubic milliliter of blood. The lower the number the less HIV is in a person's body and the less damage it causes. When a person is taking antiretroviral treatment, the aim is to get the viral load count to undetectable levels. This means that a viral load test does not give a measurable result.
It doesn't however mean that there is no HIV in a person's body. HIV may still be in "sleeping" CD4 cells that cannot be reached by antiretroviral treatment. These cells are often referred to as the latent reservoir.
There are other HIV tests that can be used to find out if a person is infected with HIV.
Some drugs have different doses based on a person's body weight, but most HIV drugs have a standard dose for adults. Some HIV drugs, but not all, need the dose to be adjusted if someone has reduced liver or kidney function.
Dosing for children is more difficult and is often worked out by age or in relation to height or weight. There is more about HIV in children.
Life expectancy for a person living with HIV
A person living with HIV who starts antiretroviral treatment today, should have the same life expectancy as an HIV negative person of the same age. Antiretroviral therapy prevents HIV related illness and disability and saves lives.
Prevention of HIV transmission
Antiretroviral therapy also has a prevention benefit. The risk of HIV transmission to an HIV negative sexual partner is estimated to be reduced by 96% if the person living with HIV is taking antiretroviral therapy.