Sulfonamides類抗生素 Treatment of urinary tract infections caused by susceptible strains of E. coli, Proteus, Klebsiella, Enterobacter, H. influenzae, S. pneumoniae, Shigella spp
藥理
Co-trimoxazole is a synergistic fixed combination of sulfamethoxazole (an intermediate-acting antibacterial sulfonamide), and trimethoprim; both sulfamethoxazole and trimethoprim are synthetic folate-antagonist anti-infectives.
藥動學
1. Both trimethoprim and sulfamethoxazole are widely distributed into body tissues and and CSF; trimethoprim also distributes into bronchial secretions.
2. Trimethoprim and sulfamethoxazole have serum half-lives of approximately 8–11 and 10–13 hours, respectively (normal renal function). In adults with creatinine clearances of 10–30 and 0–10 mL/minute, serum half-life of trimethoprim may increase to 15 and greater than 26 hours, respectively.
3. In adults with chronic renal failure, sulfamethoxazole half-life may be 3 times that in patients with normal renal function. Trimethoprim serum half-lives of about 7.7 and 5.5 hours have been reported in children less than 1 year of age and between 1 and 10 years of age, respectively.
禁忌症
1. Pregnancy, infants younger than 2 months, lactation
2. Hypersensitivity to sulfonamides or trimethoprim, patients with impaired renal or hepatic function.
懷孕分類
C
哺乳分類
Probably safe, except in premature infant or infant with G6PD deficiency.
Dosage:
8-10 mg/kg/day of TMP and 40-50 mg/kg/day of SMZ, in 2-4 equally divided doses, every 6-12 hrs for 5 days for shigellosis and up to 14 day for severe UTI Administration:
1. For all IV doses of cotrimoxazole, the drug in 100 ml of D5W per 5 ml vial over 30 minutes is recommended.
2. If fluid restriction is required, each 5ml ampule can be added to 75 ml D5W and should be administered within 2 hours.
小兒調整劑量
General dosing: Infants 2 months, Children, and Adolescents:
Oral, IV: 8 to 12 mg TMP/kg/day in divided doses every 12 hours; maximum dose: 320 mg TMP/dose.
腎功能調整劑量
1. CrCl> 30ml/min: 10-20mg/kg/day In 2-3 divided doses
2. CrCl 15-30ml/min: 5-10mg/kg/day In 2-3 divided doses
3. CrCl< 15ml/min Not recommended
肝功能調整劑量
No dosage adjustment necessary; however, avoid use in patients with suspected or confirmed sulfamethoxazole-induced liver injury unless the benefits outweigh the risks.
安定性
於125 mL D5W: 6小時;於100 mL D5W: 4小時;於75 mL D5W: 2小時 (Handbook)
注射給藥指引
給藥途徑
IVD (靜脈滴注) (仿單)
靜脈輸注液
稀釋溶液:1/2NS (MDX)。NS、D5W (仿單建議,但MDX資料顯示易產生變化)。
每瓶稀釋液體積
加入125mL稀釋液 (仿單)
注射濃度
-
給藥速率
1.5小時 (仿單)
安定性
於125 mL D5W: 6小時;於100 mL D5W: 4小時;於75 mL D5W: 2小時 (Handbook)