Treatment of initial episodes of uncomplicated urinary tract infections due to susceptible strains of organisms.
Adults: Usual: 100mg q12h or 200mg q24h for 10 days. CrCl 15-30mL/min: 50mg q12h for 10 days. Elderly: Start at lower end of dosing range.
Pediatrics: 12 yrs: Usual: 100mg q12h or 200mg q24h for 10 days. CrCl 15-30mL/min: 50mg q12h for 10 days.
Serious hypersensitivity reactions and interference with hematopoiesis (especially when administered in large dose and/or prolonged periods) rarely reported. Clinical signs such as sore throat, fever, pallor, or purpura may be early indications of serious blood disorders; obtain CBC if any of these signs are noted and d/c if significant reduction in the count of any formed blood element is found. Clostridium difficile-associated diarrhea (CDAD) reported. May result in bacterial resistance with prolonged use or use in the absence of a proven/suspected bacterial infection or a prophylactic indication; take appropriate measures if superinfection develops. Caution with possible folate deficiency, renal/hepatic impairment, and in elderly. May interfere with folic acid metabolism, serum methotrexate assay, and Jaffe alkaline picrate reaction assay. Not recommended with CrCl <15mL/min.
Tetrahydrofolic acid inhibitor; blocks the production of tetrahydrofolic acid from dihydrofolic acid by binding to and reversibly inhibiting dihydrofolate reductase, thus selectively interfering with bacterial biosynthesis of nucleic acids and proteins.
Absorption: Rapid. C=1mcg/mL; T=1-4 hrs. Distribution: Plasma protein binding
(44%); found in breast milk; crosses the placenta. Metabolism: Liver; 1- and 3-oxides and 3'- and 4'-hydroxy derivatives (principal metabolites). Elimination: Urine (50-60%, 80% unchanged),
Assess for previous hypersensitivity, megaloblastic anemia due to folate deficiency, possible folate deficiency, hepatic/renal impairment, pregnancy/nursing status, and possible drug interactions. Confirm diagnosis of causative organisms.
Monitor for signs of serious blood disorders (eg, sore throat, fever, pallor, purpura), CDAD, superinfections, renal/hepatic function. Obtain CBC if any signs of serious blood disorders are noted.
Clinical Pearl is a Continuous professional development platform with a precise and concise point of care clinical knowledge search engine and 360-degree learning cycle management platform for all healthcare professionals and organizations.