An Open Trial of Zidovudine (AZT) Treatment of the AIDS Dementia Complex in Patients With AIDS or Low CD4+ Lymphocyte Counts

Inclusion Criteria Concurrent Medication: Allowed: * Prophylactic therapy for Pneumocystis carinii pneumonia (PCP); aerosol pentamidine is the preferred method. * Maintenance anticonvulsant therapy following a seizure in the context of the AIDS dementia complex. * Patients taking anticonvulsants should have their anticonvulsant blood levels measured prior to starting zidovudine (AZT) or with changes in AZT dosage. * Phenytoin, carbamazepine, and valproic acid. * Judicious use of benzodiazepams. * For analgesia or fever, modest doses of aspirin, Tylenol, or ibuprofen. * Use of major mood or central nervous system altering drugs is discouraged and should be documented. Patients with the following are included: * An estimated pre-illness IQ = or \> 70. * A general neurodiagnostic evaluation before entry which will include a computerized tomographic (CT) scan or magnetic resonance imaging (MRI) scan and a lumbar puncture. * Stable or indolently progressive mucocutaneous Kaposi's sarcoma with \< 25 lesions and onset of \< 10 new lesions during the 30-day period prior to study entry. * Chronic seizure disorders requiring anticonvulsant therapy as long as the seizures are not associated with a fixed neurologic deficit. * A blood HIV culture and p24 antigen capture assay at the time of the lumbar puncture. A second p24 antigen assay on study entry. Informed consent form must be signed by the patient, legal guardian, or parent. Active substance abuse that would limit a patient's cooperation or evaluation. Exclusion Criteria Co-existing Condition: Patients with the following will be excluded from the study: * Active, symptomatic AIDS-associated opportunistic infections requiring ongoing maintenance therapy. * Persistent fever, active persistent diarrhea, or continued severe weight loss. * Severe premorbid psychiatric illness. * Confounding neurologic disease or deficit. * Concurrent or previous central nervous system infections or neoplasms. * Concurrent active neoplasms other than basal cell carcinoma of the skin and mucocutaneous Kaposi's sarcoma. Concurrent Medication: Excluded: * Major psychotropic medication including tricyclic antidepressants, MAO inhibitors, phenothiazines, butyrophenones, barbiturates, or amphetamines. * Cimetidine. * Ranitidine. * Probenecid. * Indomethacin. * Acyclovir (ACV) prophylaxis for recurrent Herpes simplex. Patients with the following will be excluded from the study: * Active, symptomatic AIDS-associated opportunistic infections requiring ongoing maintenance therapy. * Persistent fever, active persistent diarrhea, or continued severe weight loss. * Severe premorbid psychiatric illness. * Confounding neurologic disease or deficit. * Concurrent or previous central nervous system infections or neoplasms. * Concurrent active neoplasms other than basal cell carcinoma of the skin and mucocutaneous Kaposi's sarcoma. Prior Medication: Excluded within 2 weeks of study entry or for greater than 2 weeks of therapy: * Zidovudine (AZT). * Patients must not have previously exhibited toxic reaction to AZT. * Excluded within 30 days of study entry: * Immunomodulators and biologic response modifiers, including systemic steroids. * Any investigational agent. * Cytotoxic chemotherapy for Kaposi's sarcoma. Prior Treatment: Excluded within 30 days of study entry: * Radiation therapy. * Excluded within 2 weeks of study entry: * Blood transfusion.