Starting HIV treatment


Key points

  • It’s better to start HIV treatment sooner, rather than later.
  • Treatment will reduce the risk of HIV transmission, prevent illnesses and extend your life.
  • A range of different HIV medications are available.

Everyone who has diagnosed HIV is recommended to take HIV treatment. It's better for your health to begin HIV treatment sooner, rather than later.

Anti-HIV medications work by lowering the amount of HIV in the blood (viral load). The aim of HIV treatment is an undetectable viral load. This means that the amount of HIV in a blood sample is so low that it cannot be detected using a standard test. Reducing the amount of HIV in your blood allows your immune system (measured by your CD4 cell count) to strengthen. The higher your CD4 cell count, the lower your risk of becoming ill because of HIV (and possibly some other serious illnesses as well).

You should discuss with your doctor the best time for you to start HIV treatment. There are a number of factors you might want to consider, including:

  • The benefits of starting treatment now.
  • The potential risks if you delay starting treatment.
  • Are you ready to start treatment now?
  • Are there other factors in your life that affect your ability to start taking HIV treatment?

There may be other things which are relevant to your treatment and care and you may have other questions. It's a good idea to take some time to think about these before you go to an appointment at your clinic.

When to start treatment

The sooner you start to take HIV treatment, the sooner you can benefit from it. HIV treatment guidelines, both in the UK and elsewhere in the world, recommend that all people with HIV should take HIV treatment, regardless of their CD4 count.


undetectable viral load

A level of viral load that is too low to be picked up by the particular viral load test being used or below an agreed threshold (such as 50 copies/ml or 200 copies/ml). An undetectable viral load is the first goal of antiretroviral therapy.

CD4 cell count

A test that measures the number of CD4 cells in the blood, thus reflecting the state of the immune system. The CD4 cell count of a person who does not have HIV can be anything between 500 and 1500. When the CD4 count of an adult falls below 200, there is a high risk of opportunistic infections and serious illnesses.

viral load

Measurement of the amount of virus in a blood sample, reported as number of HIV RNA copies per milliliter of blood plasma. Viral load is an important indicator of HIV progression and of how well treatment is working. 



An association means that there is a statistical relationship between two variables. For example, when A increases, B increases. An association means that the two variables change together, but it doesn't necessarily mean that A causes B. The relationship isn't necessarily causal.

reverse transcriptase

A retroviral enzyme which converts genetic material from RNA into DNA, an essential step in the lifecycle of HIV. Several classes of anti-HIV drugs interfere with this stage of HIV’s life cycle: nucleoside reverse transcriptase inhibitors and nucleotide reverse transcriptase inhibitors (NRTIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs). 

You can start taking HIV treatment as soon as you feel ready.

In 2015 a large, well-conducted study demonstrated that there are advantages to starting treatment as soon as possible, even with high CD4 cell counts. The study clearly demonstrated that starting HIV treatment earlier has positive effects on health outcomes and reduces the risk of developing AIDS and other serious illnesses. A long-term follow-up of this study showed these benefits were still present around 10 years after joining the study. While people sometimes worry about the side effects of anti-HIV medications, the study also showed that people who began HIV treatment earlier had a better quality of life than people who waited.

Another important benefit of starting treatment is that it usually suppresses the amount of HIV in your body fluids to an ‘undetectable’ level. Having an undetectable viral load means that there's not enough HIV in your body fluids to pass HIV on during sex. In other words, you are not infectious. This is also called 'undetectable equals untransmittable' (U=U).

Other research has shown that with HIV treatment, many people living with HIV can have a relatively normal lifespan.

If your CD4 cell count is below 200, it's especially important that you begin HIV treatment as soon as possible. The lower your CD4 cell count, the greater the risk of infections and HIV making you ill.

Similarly, if you have caught HIV very recently – within the past three months – your doctor is likely to encourage you to start treatment without delay. This is because some people can become seriously ill soon after infection. Starting treatment very soon after infection reduces the chances of illness. It also gives you the best chance of having a normal immune system while living with HIV.

While the medical case for starting treatment as soon as possible is clear cut for most people, the decision to start treatment rests with the person living with HIV. Before starting treatment, it’s important that you understand how it works and what it involves. You may need a little time before you feel ready to start.

Which anti-HIV medications to start with

Standard treatment for people starting HIV treatment for the first time is a combination of three different medications. Anti-HIV medications belong to different classes depending on the way they work against HIV. The main classes of anti-HIV medications are nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), boosted protease inhibitors and integrase inhibitors. Click here to find out more about how these different classes of anti-HIV medications work.

In the UK, standards for HIV treatment and care are set by the British HIV Association (BHIVA), the professional association for HIV doctors and other healthcare professionals. Their guidelines for HIV treatment are reviewed regularly and their current recommendations for which anti-HIV medications to use are summarised on another page.

Next review date