Taking your drugs properly is often called adherence. Adherence to your HIV treatment means:

• Taking all the medicines that make up your HIV treatment combination in the right quantities.
• Taking your medicines at the right time. Taking your medicine too late can be as bad as not taking it at all.
• Following any instructions about food. Some medicines need to be taken with food so they are absorbed properly, but others need to be taken on an empty stomach.

Checking for interactions with other medicines or drugs. This includes medicines that a doctor prescribes to you, as well as those bought over the counter. It’s also important to know that some herbal and alternative medicines can interact with some anti-HIV drugs, as can some recreational and illegal drugs.

The best results of HIV treatment are seen in people who take all, or nearly all of the doses of their drugs in the right way.

Modern HIV treatment has a very powerful anti-HIV effect, but nevertheless taking fewer than 95% of your doses correctly has been associated with an increase in viral load, a fall in CD4 cell count, and an increased risk of resistance.

If you take your treatment once a day, then 95% adherence means missing no more than one dose of your HIV treatment a month.

If you take your treatment twice a day, then 95% adherence means missing no more than three doses of your HIV treatment a month.

Many people find this demanding and don’t always achieve such high levels of adherence. Despite the difficulty, it’s important to aim to take all the doses of your medication correctly, and many people find a way of making sure that they take their HIV treatment in the right way and at the right time.

You should try and make an effort to take every dose of your medication at the right time and in the right way. But most people taking HIV treatment occasionally forget to take a dose of their treatment.

What you should do about missed doses will depend on circumstances. You should still take the dose if you remember within a few hours. But don’t take your medicine if it would mean taking the dose very late. It is a good idea to discuss this with your doctor or pharmacist, as how late you can take a dose will vary, depending on the drugs you are taking. You should not take a double dose to compensate for the one you have missed.

It’s important to remember that taking doses late can be as bad as not taking them at all.

If you are regularly missing doses of your medication, or taking them late, it’s a good idea to mention this to your doctor. Your clinic should be able to offer advice and support.

A wide range of factors can have an influence on how well you adhere to your HIV treatment. These differ between people and can change over time. This means that there’s no single magic solution that can guarantee the best possible adherence for everyone.

Instead, it’s important to think about the factors that are likely to affect you. Doing this can be beneficial if you are about to start or change treatment, or if you are having problems taking your treatment properly.