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What does HIV treatment do?

HIV treatment keeps the virus under control by stopping it from reproducing itself. The goal is to keep levels of HIV so low that in tests the person has an undetectable viral load.

What does HIV treatment do?

HIV treatment keeps the virus under control by stopping it from reproducing. The goal is to keep levels of HIV so low that in tests the person has an undetectable viral load.

If someone with HIV is on effective treatment and has an undetectable viral load they cannot pass on HIV, although it can take up to six months for some people’s viral load to become undetectable.

What does being undetectable mean?

An undetectable viral load doesn’t mean HIV is not there, just that the amount of the virus in the blood is too low for tests to pick up.

Different laboratories may have different cut off points when classifying an undetectable viral load, however most clinics in the UK classify undetectable as being below 20 copies/ml.

What is effective treatment?

The term effective treatment means that someone is on HIV treatment, taking it as prescribed and has an undetectable viral load. In the UK this is usually classed as viral load below 20 copies/ml. 

The PARTNER study looked at people on treatment who had viral loads below 200 copies/ml and found no HIV transmissions among that group regardless of the presence of sexually transmitted infections (STIs).

The Partners PrEP study found that there remains a transmission risk within the first six months of treatment as the HIV positive partner's viral load takes time to come down.

Therefore effective treatment means someone has been taking it as prescribed for at least six months and has an undetectable viral load.

When should people with HIV start treatment?

It's now recommended that everyone diagnosed with HIV starts treatment straight away – regardless of their CD4 count.

In the UK, the BHIVA guidelines set out standards for HIV treatment. These guidelines were changed in September 2015 to say that anyone with HIV who is ready to commit to treatment should start taking it.

This change reflects the findings of another study, called the START study.

The START study found that people who waited to start treatment until their CD4 count dropped to 350 (which is when people were previously advised to start treatment) had a significantly higher chance of developing AIDS-related illnesses.

Treatment is working well if tests show someone has a high number of CD4 cells and a low level of HIV in their body.

What does ‘adherence’ mean and why is it important?

People take far fewer pills now than in the past - sometimes just one or two per day. Once treatment starts they must be taken every day.

Sticking to the daily dose is called adherence and good adherence is vital if treatment is to work.

If even just a few doses are missed the levels of drugs in the body fall, allowing HIV to develop resistance to them, meaning they stop working as they should.

Someone who keeps missing doses may see their viral load go up, which is bad for their health and means they can pass on HIV.

What are the side effects of HIV treatment?

HIV drugs have become more effective and easier to take. Earlier problems with side effects (such as visible changes to the face and body, called lipodystrophy) are now rare.

People may experience side effects during the first weeks of treatment (eg headaches, diarrhoea or feeling sick or tired) but once the body gets used to the drugs, these get better or go away completely.

HIV doctors work closely with their patients when treatment begins in order to find the best tolerated drug, with minimal side effects.

Their doctor will also regularly monitor their blood to check for any other issues that might be related to taking HIV drugs, and treat them if necessary.

The risks of not taking HIV medication are far greater than any risk from being on treatment.

Without treatment serious illness and death will follow within a few years for nearly everyone with HIV. They will also be able to pass on HIV to partners.

Does HIV treatment cure HIV?

No. Antiretrovirals are not a cure for HIV because they cannot completely rid the body of the virus. HIV lives on in parts of the body that drugs can’t reach – these are called ‘reservoirs’.

For this reason HIV treatment is life-long.

Effective treatment protects the immune system and if someone’s viral load is undetectable ensures they cannot pass on HIV.

How long can people on HIV treatment live?

Thanks to HIV drugs, doctors now see the infection as something that people can live very well with for a lifetime.

This is especially true if they are diagnosed early and start medication before the virus does too much damage to their immune system, in which case a person can expect to live as long as someone who doesn’t have HIV.

Thanks to medication, HIV-related illness and deaths have dropped dramatically and fewer people with HIV are infectious.

PEP - Post-exposure prophylaxis ››

‹‹ Back to: HIV postal testing with Fastest Direct



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The Information Standard: Certified member

This article was last reviewed on 20/3/2016 by Anna Peters

Date due for the next review: 20/3/2019

Content Author: Kerri Virani

Current Owner: Health promotion

More information:

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HIV treatment as prevention and HPTN 052, Cohen MS1, McCauley M, Gamble TR
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Sexual Activity Without Condoms and Risk of HIV Transmission in Serodifferent Couples When the HIV-Positive Partner Is Using Suppressive Antiretroviral Therapy, Journal of the American Medical Association: Alison J. Rodger, MD; Valentina Cambiano, PhD; Tina Bruun, RN; Pietro Vernazza, MD; Simon Collins; Jan van Lunzen, PhD; Giulio Maria Corbelli; Vicente Estrada, MD; Anna Maria Geretti, MD; Apostolos Beloukas, PhD; David Asboe, FRCP; Pompeyo Viciana, MD1; Félix Gutiérrez, MD; Bonaventura Clotet, PhD; Christian Pradier, MD; Jan Gerstoft, MD; Rainer Weber, MD; Katarina Westling, MD; Gilles Wandeler, MD; Jan M. Prins, PhD; Armin Rieger, MD; Marcel Stoeckle, MD; Tim Kümmerle, PhD; Teresa Bini, MD; Adriana Ammassari, MD; Richard Gilson, MD; Ivanka Krznaric, PhD; Matti Ristola, PhD; Robert Zangerle, MD; Pia Handberg, RN; Antonio Antela, PhD; Sris Allan, FRCP; Andrew N. Phillips, PhD; Jens Lundgren, MD, JAMA. 2016;316(2):171-181. doi:10.1001/jama.2016.5148

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Early antiretroviral treatment reduces but does not eliminate HIV reservoir, by Liz Highleyman, NAM, Aidsmap, 24/3/15

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Your treatment. NAM. 

HIV Basic Treatment. NAM.

Anti-HIV drugs. NAM.

Progression to AIDS or death. NAM.  

People doing well on HIV therapy have a mortality risk identical to that of HIV-negative peers. NAM.

Decrease in AIDS-related illness and deaths. NAM.  

Lipodystrophy. NAM.

Link with reduced infectiousness and good adherence. BHIVA.

Can't pass it on

People on effective treatment can't pass on HIV

If everyone knew this, we could bring an end to stigma and stop HIV transmissions.

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