Methenamine (INN) or hexamine (former BAN) is a chemical compound comprised of methene (methylene) and an amine. It has two very different common uses: as an antibiotic (commonly the hippurate salt, methenamine hippurate), and as a solid fuel tablet used for cooking while camping or hiking. The name hexamine is more common in non-medicinal applications.

GoldBamboo

... METHENAMINE (Hiprex®, Urex®, Mandameth®, Mandelamine®) is an antibiotic. It is used to treat cystitis (inflammation of the bladder) and to help prevent other urinary tract infections. Generic methenamine tablets or enteric-coated tablets are available. ...
Drug Digest - more...

Hexamine Chemical name 1,3,5,7-tetraazatricyclo[3.3.1.13,7]decane O ...
Wikipedia - [full article]

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