To determine a safe, effective, and convenient dosing schedule for nystatin pastilles in the prevention of oral candidiasis in patients with AIDS or AIDS related complex (ARC) (group III or IV, CDC classification).

Inclusion Criteria

Concurrent Medication:

Allowed:

• Systemic or oral antibiotics.
• Experimental drugs (IND drugs) which are targeted specifically against the AIDS (group IV CDC classification) virus or stimulate the immune system.

Patients with the following conditions are included:

• AIDS or AIDS related complex (ARC) (HIV infection Group 3 or 4, CDC classification) who have had culture-proven oral candidiasis clinically cured within 7 days of study entry and are likely to be compliant for the 20 weeks of nystatin pastille prophylaxis.
• Able to follow instructions regarding the use of a pastille.
• Patients entering part II of this study (randomized double-blind) must have been clinically cured of oral candidiasis within 1 - 7 days of entry into this randomized study.
• Oral lesions such as Kaposi's sarcoma, herpes zoster, and herpes simplex can be enrolled.

Exclusion Criteria

Co-existing Condition:

Patients with the following are excluded:

• Systemic candidiasis.
• Hypersensitivity to nystatin.
• Suspected or proven candidal esophagitis.

Patients with the following are excluded:

• Systemic candidiasis.
• Projected survival of less than 6 months.
• Unable to maintain a pastille in the buccal cavity for approximately 20 minutes twice a day.
• Hypersensitivity to nystatin.
• Suspected or proven candidal esophagitis.