AZO Urinary Tract Defense Tablets Combines: Methenamine, a powerful anti-bacterial medicine that works by slowing down the growth of the bacteria along the urinary tract and helping to control your UTI. Sodium Salicylate, a NSAID that provides general pain relief. Take AZO Urinary Tract Defense at the first sign - burning, urgency you know the drill - of a UTI to help slow the progression of the infection.8 From the #1 Most Trusted Brand in urinary health.