To determine if a pharmacokinetic (blood level) interaction exists between zidovudine (AZT) and oxazepam in the HIV-infected patient. Benzodiazepines (such as oxazepam) are among the most frequently prescribed class of drugs and are commonly used therapeutically for patients with chronic disease. This study is important because of the potential for toxicity resulting from a reaction between AZT and benzodiazepines and the likelihood of frequent use of the combination of these drugs in patients with HIV infection.