A large number of people who are infected with HIV have acquired it through injection drug use. Some of these people are currently being treated with Buprenorphine for their addiction and with medications for HIV infection. Raltegravir is a medication that was approved by the Food and Drug Administration (FDA) for the treatment of HIV infection. Raltegravir acts by making it more difficult for the virus that causes AIDS to multiply and cause more damage to the immune system in someone who is HIV infected.~Earlier studies looking at the effect of Buprenorphine and HIV medications have shown that Buprenorphine and some HIV medications act differently when taken together. It is important to learn if taking Buprenorphine and HIV medications together results in changes in the blood level of either medication. If the HIV medication affects the level of Buprenorphine in the blood, an individual taking Buprenorphine and HIV medications may experience symptoms of withdrawal, even while taking their usual dose of Buprenorphine. On the other hand, if Buprenorphine decreases the amount of HIV medication in the blood, then the HIV medication may be less effective in controlling HIV infection. It is therefore important to learn if Raltegravir and Buprenorphine will affect each other when taken together.~In order to learn about the effects of Buprenorphine and Raltegravir, we will need to measure the amount of Buprenorphine in your blood for 24 hours before you have taken Raltegravir and then compare that to the amount of Buprenorphine in your blood after you have taken Buprenorphine and Raltegravir together .
The main purpose of this protocol is to study the effect of an HIV medication known as Raltegravir on Buprenorphine in people who have been receiving the same dose of Buprenorphine for at least 3 weeks before study entry. This will be determined by giving Raltegravir along with Buprenorphine and by measuring the amount of Raltegravir and Buprenorphine in the blood. The investigators will also learn about the effects of Buprenorphine on Raltegravir and about the safety of taking these two medications together.