Trimethoprim/Sulfamethoxazole (Bactrim)
160/800 mg DS
Stop: Call 911 or get emergency help
Trouble breathing or lip/tongue swelling; fainting; severe rash with blisters, peeling, or sores; skin redness spreading fast; yellow skin/eyes; very weak/dizzy or pounding/uneven heartbeat; shaky, sweaty, or confused.
Seek medical help first
Use this information only if you are unable to contact your provider. Then, contact your provider as soon as possible.
What it may treat & how much to take
- 1
Bladder infection (UTI) in a woman
Burning or urgency; frequent small pees; lower-belly pressure; cloudy/smelly urine. No fever or back pain.
Take 1 tablet twice a day for 3 days. Provider may also prescribe phenazopyridine (see card).
- 2
Kidney infection
UTI signs + fever/chills, shaking, one-sided lower-back pain, or nausea.
Take 1 tablet twice a day for 7 days. Get medical care ASAP.
- 3
Skin infection / mild cellulitis
Skin is red, warm, swollen and tender; no pus, boil or abscess.
See amoxicillin/clavulanate card.
- 4
Skin infection with pus / abscess
Red, warm, swollen, tender skin with pus or drainage.
Seek medical care; needs to be drained. After drained: a provider may prescribe 1 tablet twice a day for 5–7 days, OR doxycycline (see card).
How to take it
Take with food and a full glass of water; drink plenty of water all day. Take doses about 12 hours apart. Finish the full course, even if you feel better. Limit sun; wear a hat, long sleeves, and sunscreen.
Important information
Get medical care if not better in 3 days, symptoms worsen, a UTI adds fever/chills/back pain, or skin redness spreads fast.
Common side effects
Upset stomach/nausea, vomiting, low appetite, loose stools, headache.
Do not take if
You have a trimethoprim/sulfamethoxazole allergy; severe liver or kidney disease, low-folate megaloblastic anemia or G6PD deficiency; or take dofetilide or methotrexate unless a doctor specifically tells you otherwise.
Ask your provider or pharmacist first if
You take warfarin; lisinopril, losartan, spironolactone or potassium; diabetes pills; phenytoin; or have porphyria or thyroid disease.
If pregnant or breastfeeding
Do not take trimethoprim/sulfamethoxazole from the kit until a doctor says it is safe.