Methenamine

Methenamine Brand Names

Hiprex | Mandelamine | Urex

What is Methenamine

Methenamine is used only for suppression and prophylaxis of frequently recurring urinary tract infections such as in patients with neurogenic bladder or in those who are intermittently catheterized.

It is not a primary agent in the treatment of urinary tract infections and should only be used after eradication of the infection by other appropriate antimicrobial agents.

Methenamine is available in the hippurate or mandelate salt formulation. All formulations of methenamine are contraindicated in patients with renal insufficiency, severe hepatic insufficiency, and severe dehydration.

Indications

  1. cystitis
  2. Enterococcus sp.
  3. Escherichia coli
  4. Proteus sp.
  5. Pseudomonas aeruginosa
  6. Staphylococcus sp.
  7. urinary tract infection (UTI)

Side Effects

  1. crystalluria
  2. dysuria
  3. elevated hepatic enzymes
  4. hematuria
  5. increased urinary frequency
  6. nausea
  7. rash

Monitoring Parameters

  • LFTs
  • serum creatinine/BUN

Contraindications

  • breast-feeding
  • dehydration
  • gout
  • hepatic disease
  • pregnancy
  • renal failure
  • renal impairment
  • tartrazine dye hypersensitivity

Methenamine, in all forms, is contraindicated in patients with renal impairment, renal failure, or severe dehydration because of the propensity for accumulation and subsequent toxicity.

Interactions

  • Acetazolamide
  • Aliskiren; Amlodipine; Hydrochlorothiazide, HCTZ
  • Aliskiren; Hydrochlorothiazide, HCTZ
  • Alkalinizing Agents
  • Aluminum Hydroxide
  • Aluminum Hydroxide; Magnesium Carbonate
  • Aluminum Hydroxide; Magnesium Hydroxide
  • Aluminum Hydroxide; Magnesium Hydroxide; Simethicone
  • Aluminum Hydroxide; Magnesium Trisilicate
  • Amiloride; Hydrochlorothiazide, HCTZ
  • Amlodipine; Hydrochlorothiazide, HCTZ; Olmesartan
  • Amlodipine; Hydrochlorothiazide, HCTZ; Valsartan
  • Amphetamine; Dextroamphetamine Salts
  • Antacids
  • Ascorbic Acid, Vitamin C
  • Atenolol; Chlorthalidone
  • Azilsartan; Chlorthalidone
  • Benazepril; Hydrochlorothiazide, HCTZ
  • Bendroflumethiazide; Nadolol
  • Benzphetamine
  • Bisoprolol; Hydrochlorothiazide, HCTZ
  • Calcium Carbonate
  • Calcium Carbonate; Magnesium Hydroxide
  • Calcium Carbonate; Risedronate
  • Calcium Carbonate; Simethicone
  • Candesartan; Hydrochlorothiazide, HCTZ
  • Captopril; Hydrochlorothiazide, HCTZ
  • Chlorothiazide
  • Chlorthalidone
  • Chlorthalidone; Clonidine
  • Citric Acid; Potassium Citrate
  • Citric Acid; Potassium Citrate; Sodium Citrate
  • Enalapril; Hydrochlorothiazide, HCTZ
  • Eprosartan; Hydrochlorothiazide, HCTZ
  • Erythromycin; Sulfisoxazole
  • food
  • Fosinopril; Hydrochlorothiazide, HCTZ
  • Hydralazine; Hydrochlorothiazide, HCTZ
  • Hydrochlorothiazide, HCTZ
  • Hydrochlorothiazide, HCTZ; Irbesartan
  • Hydrochlorothiazide, HCTZ; Lisinopril
  • Hydrochlorothiazide, HCTZ; Losartan
  • Hydrochlorothiazide, HCTZ; Methyldopa
  • Hydrochlorothiazide, HCTZ; Metoprolol
  • Hydrochlorothiazide, HCTZ; Moexipril
  • Hydrochlorothiazide, HCTZ; Olmesartan
  • Hydrochlorothiazide, HCTZ; Propranolol
  • Hydrochlorothiazide, HCTZ; Quinapril
  • Hydrochlorothiazide, HCTZ; Spironolactone
  • Hydrochlorothiazide, HCTZ; Telmisartan
  • Hydrochlorothiazide, HCTZ; Triamterene
  • Hydrochlorothiazide, HCTZ; Valsartan
  • Lisdexamfetamine
  • Magnesium Hydroxide
  • Methamphetamine
  • Methazolamide
  • Methyclothiazide
  • Metolazone
  • Phentermine; Topiramate
  • Potassium Bicarbonate
  • Potassium Chloride
  • Potassium Citrate
  • Pyrimethamine; Sulfadoxine
  • Sulfadiazine
  • Sulfamethoxazole; Trimethoprim, SMX-TMP, Cotrimoxazole
  • Sulfasalazine
  • Sulfisoxazole
  • Sulfonamides
  • Thiazide diuretics
  • Topiramate