Step 1 - It Starts with Mutations
The key to effective HIV medications is their ability to recognize the HIV virus in your blood. Without recognizing the virus, HIV medications can't work. Unfortunately, sometimes HIV makes copies of itself that are different from the original. Often this different copy is not recognized by the medications and is able to make more copies, resulting in increasing amounts of HIV in the blood. The changes that occur from one copy to another are called mutations.
Step 2 - Resistance...Not Being Recognized by the Medicines
When changes or mutations occur that result in the medicines not recognizing the virus, the HIV virus becomes resistant to the medicines. Simply put, resistance means the HIV has changed in such a way that the medicines no longer recognize the virus, meaning one or more of the medicines stop working the way they should, resulting in higher number of replication HIV particles.
Step 3 - More Resistant Copies Means Medicines that are Less and Less Effective
As the mutated HIV makes more copies of itself, the medicines become less and less effective. Eventually, the medicines will not be effective at all and will have to be changed to others that will recognize the mutated virus.
Step 4 - Which Medicines Will Work?
Unfortunately, when resistance to one medicine occurs, it can cause resistance to many medications. In fact sometimes entire classes of medicines will become resistant, limiting your medication choices in the future. But how do we know which medicines will work? There are two blood tests that will help determine which medications to choose:
- Phenotype: a test that determines how well a medication will stop HIV from making copies of itself. Read more about phenotypes...
- Genotype: a test that identifies which mutations are present. Read more about genotypes...
Step 5 - Poor Adherence = Resistance
To prevent HIV from making copies of itself, both normal and mutated copies, you must have enough medication in your blood at all times. The amount of medications in your blood decreases when doses are missed, skipped, or are late. So to make sure there is always enough medication in your blood and therefore HIV is unable to make copies of itself, you must take your medicines exactly how they are prescribed each and everyday without missing a dose.
Step 6 - Reduce Your Risk of Resistance
You can help reduce the risk of resistance by adhering to your medication regimen.
- Take your meds as prescribed, on time, each and every day.
- Learn about your meds, why you are taking them, how you should take them, and side effects you may experience.
- Get refills of your meds each month in advance so there is no doses missed while waiting for refills from your pharmacy.
- Remember that resistance will limit your medicatin options in the future.
- If you are having trouble taking your meds as prescribed, talk to your HIV physician as soon as possible.
Source: Abbott Laboratories; "HIV Resistance: An Interactive Guide"; May 2005.