Darpaz

Darpaz is contraindicated in patients hypersensitive to any of its ingredients. Risk benefits should be carefully considered when the following medical problems exist: achalasia of esophagus, atony of colon, diseases of cardiovascular system, gastrointestinal hemorrhage; glaucoma; hemolytic anemia from pyruvate kinase and G6PD deficiencies, infected urolithiasis, myasthenia gravis, paralytic ileus, severe ulcerative colitis, toxic megacolon; acute urinary retention may be precipitated in obstructive uropathy (such as bladder neck obstruction due to prostatic hypertrophy).

Cardiovascular: rapid heartbeat, flushing
Central Nervous System: blurred vision, dizziness, drowsiness
Genitourinary: difficulty micturition, acute urinary retention
Gastrointestinal: dry mouth nausea and vomiting
Respiratory: shortness of breath or trouble breathing

Serious allergic reactions to this drug are rare. Seek immediate medical attention if you notice symptoms of a serious allergic reaction, including itching, rash, severe dizziness, swelling or trouble breathing.

This medication can cause urine and sometimes stools to turn blue-green. This effect is harmless and will subside after medication is stopped.

Call your doctor or physician for medical advice about side effects. The following number does not provide medical advice, but in the U.S. you may report suspected side effects to the FDA at 1-800-FDA-1088.

This drug should not be used with the following medications because very serious interactions may occur: live influenza virus vaccine, pramlintide. Because of this products effect on gastrointestinal motility and gastric emptying, it may decrease the absorption of other oral medications during concurrent use such as: urinary alkalizers; thiazide diuretics (may cause the urine to become alkaline reducing the effectiveness of Methenamine by inhibiting its conversion to formaldehyde); antimuscarinics (concurrent use may intensify antimuscarinic effects of Hyoscyamine Sulfate because of secondary antimuscarinic activities of these medications); antacids/antidiarrheals (may reduce absorption of Hyoscyamine Sulfate, concurrent use with antacids may cause urine to become alkaline, reducing effectiveness of Methenamine by inhibiting its conversion to formaldehyde). Doses of these medications should be spaced 1 hour apart from doses of Hyoscyamine Sulfate; antimyasthenics  (concurrent use with Hyoscyamine Sulfate may further reduce intestinal motility); ketoconazole (patients should be advised to take this combination at least 2 hours after ketoconazole); monoamine oxidase (MAO) inhibitors (concurrent use may intensify antimuscarinic side effects), opioid (narcotic analgesics may result in increased risk of severe constipation); sulfonamides (these drugs may precipitate with formaldehyde in the urine, increasing the danger of crystalluria). This is not a complete list of all drug interactions. Tell your doctor or pharmacist of all presprtion mediations prior to use.

Hyoscyamine Sulfate:
Hyoscyamine Sulfate is a parasympatholytic which relaxes smooth muscles and thus produces an antispasmodic effect. It is well absorbed from the gastrointestinal tract and is rapidly distributed throughout the body tissues. Following oral administration, the drug has an onset of action of 20 to 30 minutes. The half-life is 3.5 hours. Hyoscyamine is distributed throughout the body, crosses the blood-brain barrier, and is approximately 50% bound to plasma proteins. It is metabolized in the liver to tropic acid, tropine, and Hyoscyamine glucuronide. Hyoscyamine is excreted primarily unchanged in the urine within 12 hours. Its biotransformation is hepatic.

Methenamine:
Methenamine, after oral administration, undergoes hydrolysis and gernerates formaldehyde, which provides bactericaldal or bacteriostatic action. Methenamine is rapidly absorbed from the intestinal tract and is excreted, for the most part, unchanged in the urine at which point it is hydrolyzed if the urine is acidic. It is almost completely excreted (90%) in the urine within 24 hours; of this at a pH of 5, approximately 10-30% is converted to formaldehyde in the stomach.

Phenyl Salicylate:
Phenyl Salicylate, a form of salicylic acid, is a mild analgesic for pain relief.

Sodium Biphosphate:
Sodium Biphosphate increases urinary acidity helping to maintain an acid pH necessary for the degradation or methenamine.

Methylene Blue:
Methylene Blue is a monoamine oxidase inhibitor with weak antiseptic properties. It is well absorbed by the intestinal tract and rapidly reduced to leukomethylene blue, which is stabilized in the urine. Approximately 70-80% is excreted unchanged in the urine.