human immunodeficiency virus (HIV) changes (mutates) often.
Sometimes these changes make the virus resistant to a particular
medicine or class of medicines, which means the medicine is no
longer effective against the virus. When this happens, the
medicine no longer controls virus growth (replication) or
protects the Resistance testing is done to determine whether
resistance has caused treatment to fail and to identify
antiretroviral medicines that can be used to treat the
infection. There are many reasons that treatment fails, such as:
- The virus is initially resistant to one or more antiretroviral
medicines, or the virus mutates and stops responding to the -
There is a change in the way your body absorbs a - There are
interactions between two or more medicines that you are taking.
- You have not taken your medicine as Two tests are available to
detect resistance to medicines used to treat HIV infections: -
Genotyping assays detect medicine resistance mutations in the
viral genes. It takes 1 to 2 weeks to ge