The compatibility of amifostine for injection with selected other drugs during simulated Y-site injection was evaluated. Five-milliliter samples of amifostine 10 mg/mL in 5% dextrose injection were combined with 5 mL each of 100 other drugs, including antineoplastics, anti-infectives, and supportive care drugs, in 5% dextrose injection or 0.9% sodium chloride injection. The combinations were stored under fluorescent light at 23 degrees C. The combinations were evaluated initially and at one and four hours after preparation. Visual examinations were performed in fluorescent light with the unaided eye and using a high-intensity monodirectional light beam to enhance visualization of small particles and low-level turbidity. The turbidity of each sample was measured. Particle sizing and counting were performed on selected samples. Most of the test drugs were compatible with amifostine 10 mg/mL for the observation period. However, 10 drugs exhibited various incompatibilities, including turbidity, particulate formation, precipitation, and color change. These drugs were acyclovir sodium, amphotericin B, cefoperazone sodium, chlorpromazine hydrochloride, cisplatin, ganciclovir sodium, hydroxyzine hydrochloride, miconazole, minocycline hydrochloride, and prochlorperazine edisylate. Amifostine 10 mg/mL in 5% dextrose injection was compatible with most of the 100 drugs tested for four hours at 23 degrees C. However, 10 drugs exhibited incompatibility with amifostine.