Magic Mouthwash (compounded oral rinse)

Also known as: Lidocaine/Diphenhydramine/Antacid rinse, BMX-type mouthwash

Other

In plain English

'Magic mouthwash' is a compounded rinse for painful mouth sores, especially mucositis from chemotherapy or radiation. It usually blends a numbing agent (lidocaine), an antihistamine (diphenhydramine), and an antacid to coat and soothe the mouth; some versions add other ingredients. It is swished (and often spit out) to relieve pain so patients can eat and drink. Formulas vary, and the numbing lidocaine component means dosing/frequency limits matter.

The science

These are combination rinses; the components are covered by their own entries — lidocaine (topical anesthetic, sodium-channel blockade), diphenhydramine (H1-antihistamine with local anesthetic/soothing effect), and an antacid (coating/pH buffering). They are used mainly for symptomatic relief of oral mucositis and stomatitis; evidence for specific 'magic mouthwash' formulas is modest and mostly supportive/symptomatic rather than disease-modifying.

References

• Buckley MM & Benfield P, eutectic lidocaine/prilocaine (local anesthetic pharmacology reference), Drugs 1993
• Tran AN & Koo JY, systemic toxicity with topical lidocaine (safety reference), J Drugs Dermatol 2014