Taking it

The standard dose of nevirapine (Viramune) is one 200mg tablet per day for the first 14 days on therapy and afterwards 200mg twice daily or one 400mg extended-release tablet once daily.

During the first two weeks on nevirapine, only one tablet should be taken once a day, to allow the body to establish safe levels of the drug, so reducing the risk of developing a serious rash or other side-effects. Nevirapine can be taken with or without food and at the same time as other anti-HIV drugs.

Nevirapine is also available as an oral suspension at a dose of 10mg/ml, which can be used by children weighing less than 50kg, and people who cannot take tablets.

The United States Food and Drug Administration (FDA) now recommends that if a rash with constitutional symptoms or a severe rash develops, treatment with nevirapine should be stopped. If a mild to moderate rash occurs without constitutional symptoms during the lead-in period, the nevirapine dose should not be doubled to the full dosage until the rash is gone. The lead in period of once-daily dosing should also not exceed 28 days. If the rash has not subsided, an alternative treatment should be used.¹

Those who wish to interrupt or stop nevirapine-based treatment should stop taking the nevirapine component of their regimen five days before the nucleoside reverse transcriptase inhibitor (NRTI) backbone. Since nevirapine has a long half-life and a low genetic barrier to resistance, stopping all the drugs at the same time could cause diminishing effects of nevirapine to persist much longer than those of the NRTIs, leading to the emergence of NNRTI resistance mutations.^{2 3}

If nevirapine therapy is stopped for any reason for more than seven days, the lead-in dosing of 200mg a day for 14 days should be used when the drug is resumed.

Individuals with hepatitis C/HIV co-infection may have elevated levels of nevirapine in the blood. Nevirapine is not advised for use in people with moderate or severe liver impairment.