Contracting HIV, or human immunodeficiency virus, is a serious condition, but thanks to treatment advances, the diagnosis is less severe than in previous years. However, it may take a few tries to find the most effective treatment for you. How HIV Works An HIV infection attacks cells in your immune system known as Cluster of Differentiation 4 (CD4) T cells, making it difficult for your body to fight off infections and disease. When your CD4 T cell count falls low enough--usually below 50--it’s then considered Acquired Immune Deficiency Syndrome (AIDS), the often fatal end-stage of an HIV infection. Fortunately, today there are more than 30 different medication options available that can treat HIV and prevent HIV from turning into AIDS, keeping your CD4 T cell count high and the viral load undetectable in your blood. The vast majority of patients will do very well with their first-line program of what’s known as antiretroviral therapy (ART), but unfortunately this isn’t always the case. You may experience intolerable side effects, and the treatment may even fail to work. Whatever the situation, your treatment plan may need to be changed. Don’t let that worry you too much, though. Like any other kind of medical treatment, finding what’s right for you involves some trial and error. You’ll need to take your anti-HIV medication every day for the rest of your life, so it’s important we get it right. Determining Your Anti-HIV Cocktail As part of your ART, you will take a combination of three HIV medications, known as an HIV regimen, each day. Usually we recommend taking three different drugs from two different drug classes: Nucleoside reverse transcriptase inhibitors (NRTIs): These drugs keep the virus from making copies of itself. Your ART should include two of these drugs. Integrase strand transfer inhibitors (INSTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) or protease inhibitors (PIs): Drugs in these classes block the protease enzyme and prevent the cell from producing new viruses. One of these will be the third drug in your ART. Even if your initial regimen doesn’t end up working, subsequent treatment plans should still include at least three active drugs. For convenience, many anti-HIV medication combinations can be offered as a single pill. Addressing Intolerable Side Effects You may experience a variety of minor side effects when starting anti-HIV medicine, such as fatigue, headaches and nausea, which usually subside after a few weeks as your body grows accustomed to the treatment. However, there are cases of more severe, intolerable side effects--known as drug toxicity--that can include liver damage and dangerous allergic reactions. If these more serious reactions occur, talk to your doctor immediately. Thankfully, switching treatments due to side effects is not as difficult as in the past. As long as your viral load remains low, we’ll only need to swap out one of the three drugs you’re taking. We have a wide enough variety of drug options to find the treatment cocktail that works best for you. The Possibility of Virologic Failure If your treatment just isn’t working, a less common response known as virologic failure, then changing your regimen becomes a bit more complicated. This ineffectiveness could be due to poor absorption by the body, unexpected viral resistance, or a negative interaction with a previous medication--all of which are compounded by failing to adhere to your prescribed regimen. Virologic failure essentially means your initial treatment plan is failing to keep the viral load down, and should be addressed as soon as possible. The next step is to consider both your treatment history and additional resistance testing, which will determine the most effective combination of medications for your new ART. This testing is done one of two ways: Genotypic assay, which looks for the genetic material of the HIV in your blood to determine to which drugs your virus is resistant Phenotypic assay, which evaluates how the virus responds to medication in a controlled environment In the case of viral resistance, each drug in your initial ART will mostly likely need to be changed. While a failed treatment is understandably worrisome, remember that some trial and error is to be expected. There are many options available to work to keep your viral load down, despite any treatment hiccups. Once we find the right regimen, there is no reason you can’t expect to live a long and full life.