Allopurinol mouthwash kinetic and stability information based on normal volunteers

Oral mucositis can be a major dose-limiting toxicity of fluorouracil. An encouraging early report suggested that an allopurinol mouthwash can ameliorate fluorouracil induced mucositis. Prior to testing this concept in a randomized, double-blinded clinical trial, we investigated whether there was any appreciable systemic absorption of allopurinol when used as a mouthwash. We did not detect any evidence of systemic allopurinol in 10 normal volunteers who were administered multiple small doses of allopurinol as a mouthwash. Additionally, we determined that the allopurinol mouthwash solution is stable after storage at room temperature or refrigeration for at least 8 months.