To : Rose Marie Re : Trimethoprim/sulfamethoxazole (Septra, etc) This product is a combination of trimethoprim and the sulfa drug, sulfamethoxazole. It is primarily used for urinary tract infections, but also other respiratory tract and sinus infections, otitis, etc. etc. The only major contraindication is to use this product in the last trimester of pregnancy or probably during the first 2-4 weeks of life. Sulfonamides displace bilirubin off of its protein binding site and make hyperbilirubinemia much worse, that is why it is generally contraindicated "during this time period". After the period where hyperbilirubinemia generally occurs, it is generally no problem. I have enclosed data on both the medications. This product is available in generic form and has a thousand different names, but it is almost always the same formulation. Names: Septra, Bactrim, Cotrim, Uroplus SS, Sulfatrim, and dozens of other generic names. Regards Tom Hale ----------------------------------------- Trimethoprim Fax # 1418 Trade: Proloprim, Trimpex Uses: Antibiotic AAP: Approved by the American Academy of Pediatrics for use in breastfeeding mothers Trimethoprim is an inhibitor of folic acid production in bacteria. In one study of 50 patients, average milk levels were 2.0 mg/L. Milk:plasma ratio was 1.25. In another group of mothers receiving 160 mg 2-4 times daily, concentrations of 1.2 to 5.5 mg/L were reported in milk. Because it may interfere with folate metabolism, use with caution. However, trimethoprim apparently poses few problems in full term or older infants. PHL= 14.7-40 hours (neonate), 5-6 hours (older infants). Adverse Effects: Rash, pruritus nausea, vomiting, anorexia, altered taste sensation AHL= 8-10 hours M/P= 1.25 PHL= 14.7-40 hrs (neonate) PB = 44% PK = 1-4 hours Oral= Complete References: 1. Miller RD, Salter AJ. The passage of trimethoprim/sulphamethoxazole into breast milk and its significance. In Daikos GK, ed. Progress in Chemotherapy,Proceedings of the Eighth International Congress of Chemotherapy, Athens, 1973. Athens:Hellenic Society for Chemotherapy, 687-91, 1974. 2. Pagliaro and Levin (Eds): Problems in Pediatric Drug Therapy. Drug Intelligence Publications, Hamilton, IL, 1979. ------------------------------------ Sulfamethoxazole Fax # 1392 Trade: Gantanol Uses: Sulfonamide antibiotic AAP: Not reviewed Sulfamethoxazole is a common and popular sulfonamide antimicrobial. It is secreted in breastmilk in small amounts. It has a longer half-life than other sulfonamides. Use with caution in weakened infants and premature infants with hyperbilirubinemia. Gantrisin (Sulfisoxazole) is considered the best choice of sulfonamides due to reduced transfer to infant. Compatible but exercise caution. PHL= 14.7-36.5 hours (neonate), 8-9 hours (older infants). Adverse Effects: Anemia, blood dyscrasias, allergies AHL= 10.1 hours M/P= 0.06 PHL= 36.5 hrs(neonate) PB = 62% PK = 1-4 hours Oral= Complete References: 1. Rasmussen F. Mammary excretion of sulfonamides. Acta Pharmacol Toxicol 15:138-148, 1958.