Potential side effects and toxicity: Most common side effects include headache, nausea, vomiting, fever and rash. 14-day lead-in dosing reduces the frequency of rash and incidence of drug-induced hepatitis. A serious side effect of the NNRTI class is rash, which can be life-threatening. If you experience blistering, mouth sores, conjunctivitis (redness or inflammation of eye, or pink eye, which if untreated may result in permanent vision loss), swelling, muscle or joint aches, fever or general malaise (general ill feeling), stop taking Viramune and your other anti-HIV meds and seek immediate medical attention.
Do not increase dose if rash develops during dose escalation or if you develop any rash accompanied by the above listed conditions. An increase in liver enzyme levels has been observed and in rare instances the development of hepatitis. May need to stop taking nevirapine until liver function returns to normal. Permanently discontinue if abnormalities return. Although rare, severe and life-threatening skin reactions and hepatotoxicity (liver damage), including fatal cases of each, have occurred. Women with CD4 counts greater than 250 cells/mm3 and pregnant women have a higher risk of serious hepatotoxicity (liver damage).
Potential drug interactions: Methadone dose may need to be increased due to withdrawal symptoms. Viramune reduces levels of protease inhibitors. If they are taken at the same time the doses must be increased. Crixivan should be increased to 1,000 mg every eight hours. Kaletra should be increased to four capsules twice-a-day. Viramune interacts with rifampin requiring dose adjustment, but not with rifabutin. The effectiveness of birth control pills may be decreased when taking Viramune; women and their male partners should consider the use of alternative contraception methods with barrier. During the first six weeks of therapy, prednisone should be avoided. When taken with Viramune, it can cause increased severity and incidence of rash. Avoid St. John’s wort, due to decreased levels of Viramune.
Tips: Notify your doctor of any rash, even mild. Rash may be avoided by using dose escalation schedule. Women may be at higher risk for rash. Use of Benadryl may be used to minimize symptoms of rash and to control itching but the reaction can actually be worse. A topical hydrocortisone or an oatmeal-containing cream, such as Aveeno, may improve comfort. Topical antihistamine-containing products should be avoided since there have been reports of irritation and rashes spreading. Monitor liver function tests during first six months, initially every two weeks. The increased period of risk for liver injury is primarily in the first 6–12 weeks of taking Viramune. Do not ignore yellowing of your eyes or skin, as this may be a sign of a severe liver effect. Studies show that Viramune crosses the blood-brain barrier to a useful degree, which may be beneficial for patients at risk for neurological damage (such as dementia) from HIV. Viramune has also been shown to have a positive impact on triglycerides and cholesterol levels. When given around the time of labor Viramune has demonstrated effectiveness in preventing the transmission of HIV from mother to child, but there was an increase in HIV drug resistance in the moms. Single or double dose Viramune may be used for babies born to HIV-positive mothers. Mothers should not breastfeed their infants while taking Viramune because of the potential for serious side effects.
Doctor
Nevirapine is a potent inhibitor of the virus, comparable in efficacy to efavirenz. It is dosed twice daily, but its pharmacokinetics suggest it may be used once a day. It does not have FDA approval for this dosing frequency but is used “off-label” by some providers in this way. Its main problems involve side effects. As many as 10% of patients started on the drug develop a rash. Rarely, this rash may progress to a life-threatening condition known as Stevens-Johnson syndrome. Others may develop an immune-mediated hepatitis that may also be life-threatening. Recent labeling changes have been added, warning providers to use the drug with caution when starting it in patients with higher CD4+ counts at baseline, especially women. The drug has good central nervous system penetration making it useful in patients with neurological symptoms of HIV. The primary weakness of this drug (as with Sustiva) is a very low threshold for development of resistance. A single mutation (K103N) renders this and all other non-nukes useless. Adherence to this and all agents in the non-nucleoside class is critical.—Chad J. Zawitz, MD
Activist
Viramune was the first non-nuke to be approved, and has proven to work as well as Sustiva, although some docs may not think it has the same “punch” as its competitor. It can cause a rash that can be treated without discontinuation. Viramune may have a higher incidence of symptomatic liver toxicity which consists of elevated liver enzymes plus at least one symptom, typically rash, but may include flu-like symptoms or fever. The severity of symptomatic liver toxicity ranges from mild symptoms with liver enzyme abnormalities to rapidly occurring liver failure and death. Studies have found that females have a three-fold higher risk of symptomatic Viramune liver toxicity than males, and females with CD4+ counts above 250 T-cells have a 12-fold higher risk of symptomatic liver toxicity than those with less. Males with CD4+ counts above 400 T-cells have a five-fold higher risk of symptomatic liver toxicity than those with less. Viramune has been found to prevent mother-to-child transmission in a single dose, although it needs to be used with nukes to prevent the easy emergence of HIV resistance. Because of its seeming lack of negative effects on the central nervous system, cholesterol, triglycerides, glucose, and possible lipodystrophy, Viramune is still a popular drug 10 years after approval. I would love to see studies looking at Viramune+Truvada and its effect on lipodystrophy and long term viral suppression. Many doctors are prescribing this combo without any research data backing it up.—Nelson Vergel
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