Wiktionary
n. An antiretroviral drug, an integrase inhibitor, used to treat HIV infection.
Wikipedia
Raltegravir (RAL, Isentress, formerly MK-0518) is an antiretroviral drug produced by Merck & Co., used to treat HIV infection. It received approval by the U.S. Food and Drug Administration (FDA) on 12 October 2007, the first of a new class of HIV drugs, the integrase inhibitors, to receive such approval.
In December 2011, it received FDA approval for pediatric use in patients ages 2–18, taken in pill form orally twice a day by prescription with two other antiretroviral medications to form the cocktail (most anti-HIV drugs regimens for adults and children use these cocktails). Raltegravir is available in chewable form, but because the two tablet formulations are not interchangeable, the chewable pills are only approved for use in children two to 11. Older adolescents will use the adult formulation.