The Effect of Methenamine Mandelate (Mandelamine) on Determination of Urinary Estriol

Abstract

Abstract The administration of methenamine mandelate (Mandelamine) to pregnant women causes the levels of estriol in their urines to be unmeasurably low when acid hydrolysis is used. When enzyme hydrolysis replaces acid hydrolysis, normal estriol values are obtained. This result is attributed to the formaldehyde released by acid from hexamethylenetetramine, a constituent of the drug. The formaldehyde reacts with estriol to prevent its determination.