Section 1.1

Midwives may independently prescribe, order and administer this drug.

Sulfamethoxazole-trimethoprim is a combination of two antimicrobials that act together to inhibit enzyme systems involved in bacterial DNA synthesis.

Indications and Clinical Use:

Effective in treating asymptomatic bacteriuria and uncomplicated cystitis caused by a wide variety of aerobic gram-positive and gram negative bacteria including but not limited to susceptible strains of Staphylococcus aureus, Staphylococcus albus, Staphylococcus viridans, Escherichia coli and Staphylococcus pyrogens. For use between 12 and 37 weeks of pregnancy and postpartum.


Contraindicated in the first trimester of pregnancy as sulfamethoxazole-trimethoprim decreases folate absorption and may be teratogenic. Contraindicated at term (37 or more weeks) and when onset of labour is imminent as it may cause hemolytic anemia and jaundice in infants. Contraindicated for anyone who is hypersensitive to sulfamethoxazole-trimethoprim or to any ingredient in the formulation or component of the container.

Warnings and Precautions:

Prolonged use may result in fungal or bacterial superinfection, including C. difficile-associated diarrhea (CDAD) and pseudomembranous colitis. Additional adverse effects include Stevens-Johnson syndrome, toxic epidermal necrolysis, fulminant hepatic necrosis, agranulocytosis, aplastic anemia, other blood dyscrasias and hypersensitivity of the respiratory tract. Use with caution in breastfeeding patients if the infant has G6PD deficiency or is jaundiced, ill or premature


Category D


Category L3 – Not Data- Probably Compatible

Dosage and Administration:

Cystitis: 800mg sulfamethoxazole and 160mg trimethoprim (one double strength tablet)
PO q12 hours (BID) for 3 days. Take with food.


10-12 hours


Urine and feces