benzydamine

Benzydamine, available as the hydrochloride, is a locally-acting nonsteroidal anti-inflammatory drug with local anaesthetic and analgesic properties providing both rapid and extended pain relief as well as a significant anti-inflammatory treatment for the painful inflammatory conditions of the mouth and throat.
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A substance that is being studied as a mouth rinse treatment for oral mucositis (painful mouth sores) caused by cancer therapy. It belongs to the family of nonsteroidal anti-inflammatory drugs (NSAIDS).