infectious diseases
Antiretroviral Treatment of HIV Infection
Interruption of antiretroviral therapy
Interruption of ART is usually safe if all drugs are stopped simultaneously, but levels of slowly metabolized drugs (eg,nevirapine) may remain high and thus increase the risk of resistance. Interruption may be necessary if intervening illnesses require treatment or if drug toxicity is intolerable or needs to be evaluated. After interruption to determine which drug is responsible for toxicity, clinicians can safely restart most drugs as monotherapy for up to a few days. Patients who had an adverse reaction toabacavirshould not be given the drug again. If they are reexposed to the drug, they may have a severe, potentially fatal hypersensitivity reaction. Risk of an adverse reaction toabacaviris 100-fold higher in patients with HLA-B*57:01, which can be detected by genetic testing. NOTE: The most important exception isabacavir; patients who had fever or rash during previous exposure toabacavirmay develop severe, potentially fatal hypersensitivity reactions with reexposure. Risk of an adverse reaction toabacaviris 100-fold higher in patients with HLA-B*57:01, which can be detected by genetic testing. 