Methenamine + Sodium salicylate Benzoic acid

Indications

Methenamine + Sodium salicylate Benzoic acid is used for: Urinary Tract Infection Prophylaxis

Adult Dose

Urinary Tract Infection Prophylaxis 2 tablets PO q12hr

Child Dose

Renal Dose

Administration

Contra Indications

Contraindications Methenamine Hypersensitivity to methenamine or tartrazine (FD&C Yellow No. 5) Renal or severe hepatic insufficiency Concurrent sulfonamides or acetazolamide may form insoluble precipitate in urine Sodium Salicylate Hypersensitivity to aspirin or NSAIDs Bleeding gastrointestinal ulcers Asthma, Nasal polyps associated with asthma Hemolytic anemia from PK & G6PD deficiency Hemophilia Hemorrhagic diathesis Hemorrhoids, Lactating women, Sarcoidosis, Thrombocytopenia, Ulcerative colitis

Precautions

Methenamine Large doses may cause bladder irritation, urinary frequency, albuminuria, and hematuria Maintain acidic pH of urine, especially when treating urea-splitting organisms (eg, Proteus, Pseudomonas) Monitor LFTs, especially with history of liver impairment Safe use not established during pregnancy, especially 1st and 2nd trimester May precipitate uric acid stones in patients with gout Sodium Salicylate Anemia GI malabsorption History of peptic ulcers Gout Hepatic disease Hypochlorhydria, Hypoprothrombinemia, Renal impairment, Renal calculi, Thyrotoxicosis, Vitamin K deficiency

Pregnancy-Lactation

Pregnancy Category: C Lactation: methenamine is excreted in human milk; caution advised, risk to infant cannot be ruled out

Interactions

Adverse Effects

Side effects of Methenamine + Sodium salicylate Benzoic acid : 1-10% Methenamine Dysuria Gastric upset Nausea Rash Frequency Not Defined Sodium salicylate Angioedema Bronchospasm CNS alteration Dermatologic problems GI pain/ulceration/bleeding Hepatotoxicity Hearing loss

Mechanism of Action

Methenamine: Hydrolyzed in acidic urine to ammonia and formaldehyde, which are bactericidal agents; does not convert to formaldehyde in serum. Sodium salicylate: Analgesic Benzoic acid: Elicits weak antifungal and antibacterial properties; also helps acidify urine