Source:http://linkedlifedata.com/resource/umls/id/C0025638
MSH: An anti-infective agent most commonly used in the treatment of urinary tract infections. Its anti-infective action derives from the slow release of formaldehyde by hydrolysis at acidic pH. (From Martindale, The Extra Pharmacopoeia, 30th ed, p173),NCI: A heterocyclic organic compound with antibiotic activity. In the body methenamine is converted to formaldehyde, a nonspecific bactericidal agent. Methenamine is typically used long-term to treat chronic urinary tract infections and to prevent the recurrence of infections.