Why is this drug prescribed?

Viramune tablets and suspension contain the active ingredient nevirapine, which is a type of drug called a non-nucleoside reverse transcriptase inhibitor. It is used in the treatment of HIV infection. AIDS is caused by infection with HIV. This virus invades cells of the immune system, particularly the white blood cells known as CD4 T-helper lymphocytes. These cells normally work to activate other cells in the immune system to fight infection. Since HIV kills CD4 T-helper cells, over time the body becomes less able to fight the virus or subsequent infections. Once the virus is inside the CD4 T-cell it multiplies. Part of the process of viral multiplication involves the conversion of the virus genetic material, RNA, into DNA. This is achieved by a compound essential to the virus, called reverse transcriptase. Reverse transcriptase is a compound known as an enzyme. Nevirapine works by blocking the action of this enzyme, thereby interfering with the conversion of viral RNA into DNA. This stops the virus from multiplying. There is no cure for HIV, but nevirapine is one of a number of drugs that lowers the amount of virus in the body and slows the progression of the disease from HIV to AIDS. Nevirapine is used in combination with other anti-HIV drugs that attack the HIV virus in different ways. This minimises the virus's ability to replicate and multiply, and helps prevent it becoming resistant to treatment. The most serious side effects associated with nevirapine are skin reactions and side effects on the liver, both of which can be severe or life-threatening. The risk of experiencing these side effects is minimised by starting treatment gradually. For this reason, nevirapine must be taken just once a day for the first two weeks of treatment. If no rash is experienced in this time your doctor will then increase your dose, however if you do get a rash the dose will not be increased until the rash has cleared up. If for any reason you stop taking this drug for longer than seven days during treatment, the drug will subsequently need to be re-introduced gradually, as when starting treatment. See the warnings below for further information, and make sure you talk to your doctor if you are unclear or concerned about any aspect of your treatment.

Treatments

* HIV infection.

What side effects can this drug cause?

* Rash * Nausea and vomiting * Fatigue * Headache * Fever * Diarrhoea * Abdominal pain * Pain in the muscles * Allergic reactions * Alteration in results of liver function tests * Jaundice * Severe, potentially life-threatening inflammation of the liver or liver failure * Severe, potentially life-threatening skin reactions, eg Stevens-Johnson syndrome, toxic epidermal necrolysis