Uretron D/S

Clinical summary

Indications and usage INDICATIONS AND USAGE Uretron D/S tablets are indicated for the treatment of symptoms of irritative voiding. Indicated for the relief of local symptoms, such as inflammation, hypermotility, and pain, which accompany lower urinary tract infections. Indicated for the relief of urinary tract symptoms caused by diagnostic procedures. Dosage and administration DOSAGE AND ADMINISTRATION Adults - O ne tablet orally 4 times per day followed by liberal fluid intake. Older Children - Dosage must be individualized by physician. Not recommended for use in children six years of age or younger. Warnings and cautions WARNINGS Do not exceed recommended dosage. If rapid pulse, dizziness or blurring of vision occurs discontinue use immediately. Drug interactions Drug interactions As a result of hyoscyamine's effects on gastrointestinal motility and gastric emptying, absorption of other oral medications may be decreased during concurrent use with this combination medication. Methylene blue inhibits a range of CYP isozymes in vitro, including 1A2, 2B6, 2C8, 2C9, 2C19, 2D6 and 3A4/5. This interaction could be more pronounced with narrow therapeutic index drugs that are metabolized by one of these enzymes (e.g., digoxin, warfarin, phenytoin, alfentanil, cyclosporine, dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, sirolimus and tacrolimus). However, the clinical relevance of these in vitro interactions is unknown. Urinary alkalizers and 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 because of secondary antimuscarinic activities of these medications. Antacids/antidiarrheals: Concurrent use may reduce absorption of hyoscyamine resulting in decreased therapeutic effectiveness. Concurrent use with antacids may cause urine to become alkaline reducing the effectiveness of methenamine by inhibiting its conversion to formaldehyde. Doses of these medications should be spaced 1 hour apart from doses of hyoscyamine. Antimyasthenics: Concurrent use with hyoscyamine may further reduce intestinal motility, therefore, caution is recommended. Ketoconazole and hyoscyamine may cause increased gastrointestinal pH. Concurrent administration with hyoscyamine may result in marked reduction in the absorption of ketoconazole. Patients should be advised to take this combination at least 2 hours after ketoconazole. Monoamine oxidase (MAO) inhibitors: Concurrent use with hyoscyamine 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. Patients should be advised that the urine and/or stools may become blue to blue-green as a result of the excretion of methylene blue. Pregnancy Pregnancy/Reproduction FDA Pregnancy Category C Hyoscyamine and methenamine cross the placenta. Studies concerning the effect of hyoscyamine and methenamine on pregnancy and reproduction have not been done in animals or humans. Thus it is not known whether Uretron D/S tablets cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Uretron D/S should be given to a pregnant woman only if clearly needed.