Adult Dosing

Prophylactic or suppressive treatment of frequently recurring UTIs

• 1000 mg PO bid

Pediatric Dosing

• Safety and effectiveness in pediatric patients <6 yrs of age have not been established

Prophylactic or suppressive treatment of frequently recurring UTIs

• >12 yrs: 1000 mg PO bid
• 6-12 yrs: 500-1000 mg PO bid

[Outline]

• Adult Dosing
• Pediatric Dosing

• For prophylactic or suppressive treatment of frequently recurring UTIs when long-term therapy is considered necessary

• Hypersensitivity to any of the ingredients of the product
• Renal insufficiency
• Severe hepatic insufficiency
• Severe dehydration
• Patients on sulfonamides

• N/A

Renal Dose Adjustment

• Renal impairment: Contraindicated

Hepatic Dose Adjustment

• Severe hepatic impairment: Contraindicated

• Incidence of bladder irritation, painful and frequent micturition, albuminuria, and gross hematuria have occurred during therapy with large doses of methenamine (8 g daily for 3-4 wks)
• Care should be taken to maintain an acid pH of the urine, especially when treating infections due to urea-splitting organisms such as proteus and strains of pseudomonas
• Perform periodic LFTs during therapy and especially in those with liver dysfunction; a slight increase in serum transaminase levels has been reported in some cases
• During pregnancy, drug may interfere with laboratory tests of urine estriol (resulting in unmeasurable low values)
• This product contains tartrazine, which may cause allergic-type reactions such as bronchial asthma in susceptible patients
• Methenamine is used for the treatment of bacterial infections and not for viral infections (e.g., the common cold)
• It should be used to treat or prevent infections that are proven or strongly suspected to be caused by bacteria in order to reduce the development of drug-resistant bacteria and maintain its effectiveness

Caution: Use cautiously in

• Mild to moderate hepatic impairment

Pregnancy Category:C

Breastfeeding: Low amounts of salts of methenamine (hippurate and mandelate) pass into milk and appears acceptable to use, even while nursing a newborn. This information is based upon LactMed database (available at http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT last accessed 30 March 2011). As per manufacturer's data, because of the possibility of serious adverse reactions in breastfed infants, a decision should be made whether to discontinue nursing or discontinue the drug, analyzing the importance of the drug to the mother.

• GI: Nausea, upset stomach, increase in liver transaminases
• GU: Dysuria, gross hematuria, crystalluria, albuminuria
• DERM: Rash

• Anti-infective agent; it is hydrolyzed to formaldehyde and ammonia in acidic urine; formaldehyde has nonspecific bactericidal action. Other components, hippuric acid or mandelic acid, aid in maintaining urine acidity and may aid in suppressing bacteria
• Metabolized in urine; active metabolite: Formaldehyde
• Renally excreted: >90%
• Half-life: Approximately 4.3 hrs

US Trade Name(s)

• Hiprex
• Urex

US Availability

methenamine (generic)

• TABS: 1000 mg

Hiprex, Urex

• TABS: 1000 mg

Canadian Trade Name(s)

• Mandelamine

Canadian Availability

Mandelamine

• TABS: 500 mg

UK Trade Name(s)

• Hiprex

UK Availability

Hiprex

• TABS: 1000 mg

Australian Trade Name(s)

• Hiprex

Australian Availability

Hiprex

• TABS: 1000 mg

[Outline]

Antimicrobials

Antibiotics

Urinary Antibiotics

Infectious Disease

Antibiotics

Urinary Antibiotics

Urologic

Antibiotics

Urinary Antibiotics

Pricing data from www.DrugStore.com in U.S.A.

• Hiprex 1 GM TABS [Bottle] (SANOFI-AVENTIS U.S.)
  20 gm = $53.99
  60 gm = $151.17

Warning: This pricing information is subject to change at the sole discretion of DS Pharmacy. For the most current and up-to-date pricing information, please visit drugstore.com.

• Hiprex 1000 MG Oral Tablet (sanofi-aventis U.S. LLC)
• Methenamine hippurate 1 GM Oral Tablet (Corepharma LLC)
• Methenamine hippurate 1 GM Oral Tablet (County Line Pharmaceuticals, LLC)
• Methenamine hippurate 1 GM Oral Tablet (Rising Pharmaceuticals Inc)