Reasons a combination can fail

If your viral load rebounds it is important to find out why.

This is to help make sure the next combination will work.

Your doctor will need your help to find out which of the reasons below are most important.

There are more than 30 HIV drugs and formulations. However, there are only a limited number of combinations.

This is because resistance to one drug can limit the use of other drugs that are similar.

1) Information. Maybe you did not have enough information or support to understand how to get the best from your meds. Take control of your own health. Ask questions about treatment until you are happy with the answers.Talk to your doctor, health advisors and friends.

Read leaflets and websites. Ask for help.

2) Adherence. You might have missed doses or been late taking your meds. Your doctor is likely to talk about adherence first. Be as honest as you can when discussing this.If you did not miss doses it is important that your doctor believes you. See these tips.
3) Taking meds with or without food. Some drugs need to be taken with food and others without food to reach the right levels. Check that you had the right information. Not following this advice might mean you were only getting half the dose.
4) Low drug levels. You were taking your drugs on time but they were not absorbed properly. Some people absorb low drug levels.This is less common with modern meds but may still be worth checking.. Drug levels can be checked for most drugs except NRTIs (*nukes”).
5) Drug resistance before treatment. Resistance might have been missed before you started. Even taking all your meds on time can’t overcome drug resistance. Get a new resistance test and an expert review of previous tests.This will help choose your next drugs.
6) If your combination had side effects. No matter how good your combination is, if you have difficult side effects, or it is too difficult to take, then ask if there are other options. Use new drugs that are still likely to be active.If side effects were a reason for missing doses, it is important that your doctor knows this.There are likely to be other meds you can use.
7) Drug interactions may have reduced the drug levels of your HIV drugs. Other medications or supplements can interact with HIV drugs.This includes meds you can buy over the counter without a prescription.It can include vitamins and minerals and some recreational drugs.

Your HIV doctor and pharmacist need to know about all your drugs and supplements. This is to check for potential interactions.


8) The drugs in your last combinations. Some drugs are not recommended at high viral loads.

Check that the drugs in your last combination were right for your viral load.

Last updated: 1 January 2018.