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Home > Health Library > Resistance to HIV Medicines
The human immunodeficiency virus (HIV) changes (mutates) often. Sometimes these changes make the virus resistant to a medicine or class of medicines. This means the medicine no longer works against the virus. When this happens, treatment can fail. The medicine no longer controls virus growth (replication) or protects the immune system.
Here are some reasons why treatment fails.
Resistance reduces the number of treatment options in the future. So it is important to keep resistance from happening.
You may be tested for infection with a resistant virus when:
Two tests can find a resistant virus:
Both of these tests are done on a sample of blood taken from a vein. These tests may not be accurate if the resistant virus is less than 20% of the circulating virus.
Current as of:
July 1, 2021
Author: Healthwise StaffMedical Review: E. Gregory Thompson MD - Internal MedicineAdam Husney MD - Family MedicinePeter Shalit MD, PhD - Internal Medicine
Current as of: July 1, 2021
Author: Healthwise Staff
Medical Review:E. Gregory Thompson MD - Internal Medicine & Adam Husney MD - Family Medicine & Peter Shalit MD, PhD - Internal Medicine
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