Last reviewed 2026-04-20 · How we verify

Hiprex (METHENAMINE)

Hiprex (METHENAMINE) is a small molecule drug developed by CNTY LINE PHARMS and currently owned by Esjay Pharma. It is used to prevent and treat bacterial urinary tract infections. Hiprex is an off-patent medication with multiple generic manufacturers. It was first approved by the FDA in 1967 for the prevention of bacterial urinary tract infections and urinary tract infectious diseases. As an off-patent medication, Hiprex is widely available in the market.

At a glance

Approved indications

• Prevention of Bacterial Urinary Tract Infection
• Urinary tract infectious disease

Common side effects

• Nausea
• Upset stomach
• Dysuria
• Rash

Key clinical trials

• Efficacy and Mechanism of Action of Methenamine Hippurate (Hiprex™) in Women With Recurring Urinary Tract Infections. (PHASE4)
• A Clinical Trial of Extended (High) Treatment Dose Antibiotics in Combination With Methenamine Hippurate Compared to the Standard of Care (Either Prophylactic (Low) Dose Antibiotic Treatment or Methenamine Hippurate) in Females With Chronic Urinary Tract Infection (PHASE2)
• Vitamin C and Hiprex in rUTI (EARLY_PHASE1)
• Methenamine Hippurate Following Intradetrusor OnabotulinumtoxinA Injection (PHASE4)
• A Multidisciplinary, Multimodal Bundled Care Approach to Chronic Pelvic Pain (PHASE3)
• Is Methenamine Prophylaxis for Urinary Tract Infection After Midurethral Sling as Effective as Antibiotic Prophylaxis? (NA)
• The Effect of Methenamine Hippurate to Reduce Antibiotic Prescribing in Elderly Women With Recurrent UTI (PHASE4)
• Oral Probiotic Supplementation in Pregnancy to Reduce Group B Streptococcus Colonization (PHASE3)

Primary sources

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