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The goal of anti-HIV treatment is to reduce the amount of HIV in the body. The treatment should stop you from becoming ill for many years. Sometimes the antiretroviral therapy works without any major problems or setbacks, but sometimes there can be problems. The antiretroviral drugs have not been available for very long, and despite on-going research and development, there are certain problems and issues associated with anti-HIV treatment. Here you can find some information about the issues that you may face when continuing your antiretroviral treatment. The following information continues from the pages introduction to treatment and starting antiretroviral treatment. Drug ResistanceAntiretroviral drugs slow down the reproduction of HIV in the body. But the drugs cannot stop the reproduction of HIV completely, and so some HIV is able to survive despite on-going treatment. HIV reproduces itself very quickly and when reproducing often makes slight mistakes. So each new generation, or new strain, of HIV differs slightly from the one before. These tiny differences in the structure of HIV are called mutations. Some of the mutations occur in the parts of HIV which are targeted by anti-HIV drugs. So although you have some HIV that continues to be affected by the drugs, you have other strains of HIV that are not affected by the anti-HIV drugs as effectively as before. This HIV is called drug resistant HIV, and it is then able to reproduce unaffected by the drugs. When someone has drug resistant HIV (commonly referred to as drug resistance), the amount of HIV in the blood rises and the risk of the person becoming ill increases. Drug resistance is one of the main reasons why antiretroviral treatment fails. If resistance to the current drug treatment is developed, this usually means that the drug regime needs to be changed. The viral load test can reveal developing drug resistance. Normally when treatment is started, the viral load drops to the undetectable level. A sign of developing resistance is if the viral load increases. In some countries, the resistance to certain drugs can be monitored by using specific resistance testing: genotypic and phenotypic testing. Avoiding resistanceThere are certain things that can be done to minimalise the risk of developing drug resistant HIV. If the drug combination is strong, and HIV is not able to mutate, there is less risk of resistance developing. This often means taking a combination of 3 or 4 drugs. Regular viral load testing. The viral load test can indicate if you are developing a drug resistant strain of HIV. If the drug combination is working, the viral load should be undetectable. If the viral load has increased, this can be a sign of growing drug resistance. Taking drugs exactly as prescribed is a very important part of avoiding resistance. Missing doses or not taking them on time, lowers the amount of drug in your body and the virus is not properly suppressed. Then the virus is able to reproduce itself faster and there is an increased risk of developing resistance. Cross-resistanceDeveloping resistance to some antiretroviral drugs can limit which treatment options are available to you in the future. If HIV is resistant to one drug, it will sometimes be resistant to similar drugs in the same group. This is called cross-resistance and it means that some anti-HIV drugs will not work even though you have not used them before. Cross-resistance is a particular problem if a person develops cross-resistance to a whole group of drugs. For example, if a person has developed a resistance to one of the non-nucleoside drugs, there is a risk that none of the other non-nucleosides will be effective. Infection with Drug-Resistant HIVPeople can be infected with a drug-resistant strain of HIV. The wide use of antiretrovirals in the developed parts of the world has caused drug-resistant strains of HIV to emerge. This virus is already resistant to some antiretroviral drugs. Becoming infected with the drug-resistant HIV can limit the treatment options available to you. Side-effectsDrugs are generally licensed and tested to treat specific illnesses. What is referred toas side-effects is when the drugs affect the body in ways other than those that are intended. Most of the anti-HIV drugs have side-effects. It does not mean that everyone who takes them will experience side-effects. Generally, you cannot predict if you are likely to experience side-effects or not. Some people only experience the side-effects mildly and find them easily manageable. But for some people the side-effects occur so strongly that they have to consider other alternative drugs. The most common side-effects are nausea and feeling tired. Side-effects are often referred to by the grade of the effect, and the grades range from mild to moderate to severe to life-threatening*. For example, it is considered a mild side-effect if a person has 2-3 vomiting episodes a day. Life-threatening side-effects such as extreme limitations in daily activity and hospitalisation are rare, but are still threats to some. When drugs are developed they go through clinical trials. A clinical trial is a study with people to test how well the new drugs or treatment works and how safe it is. Some long-term side effects may not be noticed in the clinical trials. It is hard for the researchers to draw consistent information on side-effects in clinical trials, since people have different treatment histories, general health and tolerability levels. Therefore, some side-effects only become apparent after the drugs have been approved and have been used by more people over a longer period. Since HIV is a life-threatening disease, there is a constant need for new drugs. Sometimes it is important to get a drug on the market despite known side-effects. Many patients and health professionals agree that the anti-HIV drugs are far from perfect and the tolerability and side effects of the drugs need to be vastly improved. It can be useful to find out about the possible side-effects that particular drugs have, before you start treatment. The side-effects often get better after you have been on the treatment for a little while, as the body then starts to adjust to the anti-HIV drugs. Some people use alternative therapies and medications with the combination therapy to ease the side-effects. For example, some people find taking peppermint eases their feeling of nausea. Sometimes the side-effects do not diminish over time, and in some instances one or more of the drugs in the combination can be changed to reduce the side-effects. If you feel that the side-effects are too much to cope with, you should always seek help from your doctor before changing or stopping your regime. Adherence and side-effectsThe term adherence means taking the drugs exactly as described. Adherence is a very important part of anti-HIV treatment. Often experiencing side-effects makes adherence difficult. Your doctor might be able to give you some treatment to help with the most common side-effects such as nausea and diarrhoea. As adherence is such an important part of treatment, it is important to monitor closely the effect that side-effects have on your adherence. If the side-effects are affecting adherence, you must tell your doctor. Changing treatmentA drug combination can fail for a number of reasons which include:
There are two main reasons why anti-HIV treatment sometimes needs to be changed. Firstly, a change of treatment is needed when the antiretrovirals fail to work and slow down the reproduction of the virus in the body. Increased viral load or an HIV-related illness are signs of failing anti-HIV treatment. The drug combinations often cause side-effects. Sometimes these side-effects are so strong, intolerable and even life-threatening that the treatment must be changed. Monitoring the viral load carefully is an important part of treatment. There are different opinions about the 'right time' to change the treatment if your viral load is rising. Some doctors recommend changing the treatment as soon as the viral load starts to rise. Others recommend monitoring the overall trend of the viral load before making a decision to change. Changing the drugs earlier rather than later, could mean running out of treatment options quicker. But changing later, means there is a danger of developing resistance to certain drugs. This can seriously limit your future treatment options. The changes that can be made to the drug regime will depend on the drugs already being used, the CD4 count and your general health. The anti-HIV drugs work the best when used the first time. This is one of the reasons why it has to be considered carefully whether a change of treatment is necessary or not. The combination of anti-HIV drugs other than the first or second treatment is called salvage therapy. It is also referred as second-line, third-line or rescue therapy. Many people start their salvage therapy with much higher levels of viral load than previous treatments. This puts more pressure on the new combination to work. Each combination used lessens the chance of maintaining a low viral load because of the possibility of developing resistance to the drugs. The choice of new treatment should always depend on what caused the previous one to fail. If you have an increased viral load, strong side-effects or need to change your anti-HIV treatment for any other reasons - always contact your doctor before taking any action. Structured Treatment Interruptions (STIs)Structured Treatment Interruptions (STIs) or drug holidays are the terms used when someone is stopping taking anti-HIV treatment for a certain period of time. People take treatment interruptions for a variety of reasons, such as side-effects, ineffectiveness of the drugs and psychological matters. STI does not mean skipping or stopping your medication randomly, but taking a break from your drug regime with a planned timescale, close monitoring and help from your doctor. In theory, STIs have benefits such as stimulating the immune system, reducing side-effects and lowering the cost of medication. Enjoying a drug-free period is also believed to have some psychological benefits such as increased adherence when returning to treatment. If the immune system responds well to the STI, it often means there is the possibility of a longer drug-free period. However, after a period without anti-HIV drugs, most people have to start their treatment again. Some studies have found that people who were resistant to certain antiretrovirals were less resistant to the same drugs after a treatment break. The main risks of using a treatment break are that the viral load will rise and the CD4 count will drop. This may increase the risk of becoming ill. Also, stopping and re-starting the treatment could make it easier for the virus to develop resistance to the anti-HIV drugs. Some research has been carried out about the benefits and risks of interrupting anti-HIV treatments. However, long-term effects are unknown. STIs are not widely recommended for general use at the present. If you are considering treatment interruption or stopping your treatment - always talk to your doctor first. Taking unsupervised treatment breaks can do more harm than good to your health and limit you treatment options in the future. * Based on the grading by US NIH Division of AIDS See our other pages for more information about treatment: Introduction to HIV and AIDS treatment, Starting HIV Treatment, HIV and AIDS news (including treatment), HIV/AIDS Treatment Booklet and HIV/AIDS Treatment Glossary. Last updated January 20, 2005 |