Inclusion Criteria

Inclusion Criteria

Concurrent Medication:

Allowed:

- Anti-HIV therapy provided therapy has remained constant in the 4 weeks prior to study
entry.

- Narcotic analgesia after the first week of treatment ONLY IF the patient is not
experiencing somnolence.

Patients must have:

- Documented HIV infection or AIDS.

- Biopsy-confirmed aphthous ulceration of the mouth or esophagus lasting at least 2
weeks.

- Negative culture of ulcer for Herpes simplex.

- En face diameter of >= 5 mm for largest aphthous ulcer.

- Life expectancy of at least 3 months.

NOTE:

- This study is approved for prisoner participation.

Exclusion Criteria

Co-existing Condition:

Patients with the following symptoms or conditions are excluded:

- Known allergy to thalidomide.

- Grade 2 or worse bilateral peripheral neuropathy.

EXCLUDED FOR MAINTENANCE PHASE:

- Toxicity other than somnolence in acute phase that required discontinuation of drug.

Concurrent Medication:

Excluded:

- Acute therapy for opportunistic infection.

- ddC.

- Pentoxifylline.

- Methotrexate, trimetrexate, antineoplastic alkylating agents.

- Other putative immunomodulators.

- CNS depressants and/or medications with sedative or hypnotic effect.

- Systemic and/or oral topical corticosteroids.

- Systemic chemotherapy for Kaposi's sarcoma or other malignancies.

- Compounded antibacterial mouthwashes containing anti-infective agents (such as
doxycycline, minocycline, tetracycline, or nystatin).

Concurrent Treatment:

Excluded:

- Radiation to head and/or neck.

Patients with the following prior conditions are excluded:

- History of grade 2 or worse bilateral peripheral neuropathy.

- Change in anti-HIV therapy within 4 weeks prior to study entry.

- Prior enrollment in ACTG 251 or prior treatment of aphthous ulcers with thalidomide.

Prior Medication:

Excluded:

- Systemic and/or oral topical corticosteroids within 1 week prior to first set of
bloods drawn.

- Other putative immunomodulators within 2 weeks prior to study entry.

- Prior thalidomide for aphthous ulcers.