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Sulfadoxine/pyrimethamine (By mouth)

Pyrimethamine (pir-i-METH-a-meen), Sulfadoxine (sul-fa-DOX-een)

Treats or helps prevent malaria, an infection that can be serious, even life-threatening.

Brand Name(s):

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

You should not use this medicine if you have had an allergic reaction to any sulfa drug or to pyrimethamine. You should not use this medicine if you are breast feeding, or if you have megaloblastic anemia due to folate deficiency. This medicine should not be given to infants under 2 months of age.

How to Use This Medicine:


  • Your doctor will tell you how much medicine to use. Do not use more than directed. This medicine should be taken after a meal. Swallow the tablet whole. Do not crush, break, or chew it.
  • Drink extra fluids so you will urinate more often and help prevent kidney problems.
  • Take all of the medicine in your prescription to clear up your infection, even if you feel better after the first few doses.

If a dose is missed:

  • Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose. Do not use two doses at the same time.

How to Store and Dispose of This Medicine:

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep all medicine out of the reach of children. Never share your medicine with anyone.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Make sure your doctor knows if you are also taking chloroquine (Aralen®), or sulfa antibiotics such as Cotrim®, Septra®, or Bactrim®.

Warnings While Using This Medicine:

  • Make sure your doctor knows if you are pregnant or breast feeding, or if you have kidney problems, liver disease, or any blood problems. Tell your doctor if you have a history of folate (vitamin) deficiency, severe allergies, or asthma. Make sure your doctor knows if you have had an allergic reaction to a diuretic ("water pill") or a medicine taken by mouth to treat diabetes (high blood sugar).
  • If you develop a skin rash, stop taking this medicine immediately and see a doctor right away.
  • Becoming pregnant while using this medicine, or within three months after your last dose of this medicine, may harm your unborn baby. Use two forms of birth control to avoid getting pregnant while you are using this medicine. Keep using two forms for at least 3 months after your treatment ends.
  • If you are taking this medicine to keep from getting malaria, it is important that you also take other steps to protect yourself against the illness. Wear protective clothing, use insect repellants, and use bed nets to further decrease your risk of getting malaria. If you become ill and have a fever after returning from a malaria-prone area, call your doctor right away. Let your doctor know that you have been to an area where malaria infection is possible.
  • This medicine may make your skin more sensitive to sunlight. Wear sunscreen. Do not use sunlamps or tanning beds.
  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Abdominal (belly) pain.
  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Blistering, peeling, or red skin rash, skin sores, or painful skin.
  • Chest pain or tightness, or an uneven heartbeat.
  • Eye pain, eyes sensitive to light, or eye discharge (pus or mucus).
  • Extreme tiredness.
  • Seizures or hallucinations (seeing or sensing things that are not there).
  • Sores in your mouth or throat.
  • Unexplained fever, sore throat, body aches, wheezing, or cough.
  • Unusual bleeding or bruising.
  • Yellowing of your skin or the whites of your eyes.

If you notice these less serious side effects, talk with your doctor:

  • Diarrhea
  • Headache, ringing in your ears, or dizziness.
  • Irritability, nervousness, or other mood changes
  • Nausea, vomiting, or upset stomach.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 8/28/2020

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