Reuters 4 Jan. '01

Atlanta -- Health-care workers who take nevirapine after possible occupational exposure to the AIDS virus risk potentially life-threatening side effects from the anti-AIDS drug, federal health officials said on Thursday.

The Centers for Disease Control and Prevention (CDC) said it found 22 reported cases of serious side effects among people who took the drug fearing exposure to HIV, the virus that causes AIDS, because of a needlestick or similar injury.

Dr. Elise Beltrami of the CDC's National Center for HIV, STD and TB Prevention said the side effects have included liver toxicity and severe skin reactions. In one case, a 43-year-old health-care worker needed a liver transplant after suffering liver failure.

Nevirapine, sold under the name Viramune, is approved for use as an antiviral drug for people with HIV infection. It is also used to prevent transmission of HIV from a pregnant woman to her child.

However, the CDC said that because most occupational exposures to HIV do not result in transmission of the virus, the risk of side effects from nevirapine should be balanced against the risk of HIV transmission.

"In this setting, the risk of HIV transmission is very low and, in most cases, the risk of taking nevirapine would outweigh the risk of using it for possible prevention of HIV,'' Beltrami said.

The drug's manufacturer, Boehringer Ingelheim/Roxane Laboratories, Inc., notified health professionals in November that it was strengthening product package warnings because of continued reports of "severe, life-threatening and in some cases, fatal hepatotoxicity.''

Beltrami said the adverse reactions reported among health- care workers "do not, in any way, apply to the use of nevirapine in other settings.''

"Nevirapine has been shown to be safe as a single-dose treatment for prevention of perinataltransmission of HIV,'' Beltrami said.

"It also should not affect the use of nevirapine for HIV-infected individuals where nevirapine can be used in combination with other anti-retroviral agents with appropriate monitoring,'' she said.