Patients are randomized to receive thioctic acid alone, deprenyl alone, thioctic acid/deprenyl, or placebo alone for 10 weeks, after which all patients may receive active drug on an open-label basis. Patients must have seven clinic visits.

Inclusion Criteria

Concurrent Medication:

Allowed:

• Antiretrovirals provided dose has been stable for at least 6 weeks prior to study entry.

Patients must have:

• HIV seropositivity.
• Mild to moderate cognitive impairment (problems with short term memory, concentration, and feeling slowed down).
• No active opportunistic CNS infection.
• Ability to give informed consent.

Prior Medication:

Allowed:

• Prior antiretrovirals provided dose has been stable for at least the past 6 weeks.
• Prior thioctic acid or deprenyl.

Exclusion Criteria

Co-existing Condition:

Patients with the following symptoms or conditions are excluded:

• Severe premorbid psychiatric illness including schizophrenia and major depression that would interfere with study compliance.
• CNS neoplasms.
• Any other clinically significant condition or laboratory abnormality that would preclude participation on study.
• Current participation in other drug studies.

Concurrent Medication:

Excluded:

• Chemotherapy for malignancy.

Patients with the following prior conditions are excluded:

• History of chronic neurological disorders such as serious head injury, documented stroke, multiple sclerosis, uncontrolled epilepsy, Tourette's syndrome, and other neurodegenerative processes such as Huntington's disease.
• Prior participation in this study.
• History of adverse reaction/allergy to thioctic acid or deprenyl.

Prior Medication:

Excluded:

• Other investigational drugs within 30 days prior to study entry.