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What does HIV treatment do?

HIV treatment protects your immune system and, if your viral load is undetectable, ensures you cannot pass on HIV.

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.

Viral load can increase again if the person with HIV stops taking their treatment.

An undetectable viral load means someone with HIV cannot pass the virus on.

The British HIV Association (BHIVA) now recommends that everyone diagnosed with HIV starts treatment straight away. This is because starting earlier is proven to keep people with HIV healthier.

Treatment as Prevention (TasP)

The lower the amount of HIV in the blood, the better for someone’s health. The PARTNER study has also found that people who are on treatment with an undetectable viral load cannot pass on HIV.

Treatment as Prevention (TasP) means placing HIV positive people on HIV treatment with the aim of their viral load becoming undetectable to ensure that they cannot pass on HIV.

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.

Your doctor will also regularly monitor your 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.

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 ››

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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:

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

Viral load, Michael Carter, Greta Hughson, NAM, Aidsmap, March 2014

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Is there a cure for HIV and AIDS?, Avert, 1/5/15

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

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How HIV destroys the immune cells, by Dan Cossins, The Scientist, 19/12/13

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What does taking your HIV treatment involve?, NAM, Aidsmap, March 2014

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Link with reduced infectiousness and good adherence. BHIVA.

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The easiest and most effective precaution to take against most STIs is using a condom.