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Generic Name: pyrimethamine/sulfadoxine (peer-i-METH-a-meen/sul-fa-DOX-een)
Brand Name: Fansidar
Severe and sometimes fatal reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis, have been associated with the use of pyrimethamine/sulfadoxine. Contact your doctor immediately if you develop signs of infection (eg, fever, chills, sore throat), unusual tiredness or weakness, unusual bruising or bleeding, a skin rash, or if you develop red, swollen, or blistered skin.
Pyrimethamine/ sulfadoxine is used for:
Treating and preventing malaria when other medicines (eg, chloroquine) are not effective or appropriate.
Pyrimethamine/sulfadoxine is an antimalarial agent. It works by blocking the formation of folinic acid within the malaria organism, which kills the parasite.
Do NOT use pyrimethamine/ sulfadoxine if:
- you are allergic to pyrimethamine or any other ingredient in pyrimethamine/sulfadoxine
- you are pregnant and at term or you are breast-feeding
- you have had a severe allergic reaction (eg, severe rash, hives, difficulty breathing, dizziness) to any other sulfonamide medicine, such as acetazolamide, celecoxib, certain diuretics (eg, hydrochlorothiazide), glyburide, probenecid, sulfamethoxazole, valdecoxib, or zonisamide
- you have severe kidney or liver problems or certain blood problems (eg, anemia due to folate deficiency)
- the patient being treated is younger than 2 months of age
Contact your doctor or health care provider right away if any of these apply to you.
Before using pyrimethamine/ sulfadoxine:
Some medical conditions may interact with pyrimethamine/sulfadoxine. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are planning to become pregnant
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have a history of asthma, severe allergies, kidney or liver problems, the blood disease porphyria or other blood problems, glucose-6-phosphate dehydrogenase (G-6-PD) deficiency, seizures, alcohol abuse, or depression
- if you have diarrhea, a stomach or intestinal infection, or a sore throat
Some MEDICINES MAY INTERACT with pyrimethamine/sulfadoxine. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Methotrexate because side effects may be increased by pyrimethamine/sulfadoxine
This may not be a complete list of all interactions that may occur. Ask your health care provider if pyrimethamine/sulfadoxine may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use pyrimethamine/ sulfadoxine:
Use pyrimethamine/sulfadoxine as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Take pyrimethamine/sulfadoxine after a meal.
- Swallow pyrimethamine/sulfadoxine whole. Do not break, crush, or chew before swallowing.
- Drinking extra fluids while you are taking pyrimethamine/sulfadoxine is recommended. Check with your doctor for instructions.
- If you miss a dose of pyrimethamine/sulfadoxine, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.
Ask your health care provider any questions you may have about how to use pyrimethamine/sulfadoxine.
Important safety information:
- Pyrimethamine/sulfadoxine may cause dizziness. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to pyrimethamine/sulfadoxine. Using pyrimethamine/sulfadoxine alone, with certain other medicines, or with alcohol may lessen your ability to drive or perform other potentially dangerous tasks.
- If you have had a severe allergic reaction to pyrimethamine/sulfadoxine or any other sulfonamide medicine (eg, sulfisoxazole, sulfamethoxazole, glyburide, probenecid), contact your doctor or pharmacist before taking pyrimethamine/sulfadoxine. A severe reaction includes a severe rash, hives, breathing difficulties, or dizziness. If you have a question about whether you are allergic to pyrimethamine/sulfadoxine or if a certain medicine is a sulfonamide, contact your doctor or pharmacist.
- It is important to use pyrimethamine/sulfadoxine for the full course of treatment. Failure to do so may decrease the effectiveness of pyrimethamine/sulfadoxine and increase the risk that the bacteria will no longer be sensitive to pyrimethamine/sulfadoxine and will not be able to be treated by this or certain other antibiotics in the future.
- Pyrimethamine/sulfadoxine may reduce the number of clot-forming cells (platelets) in your blood. To prevent bleeding, avoid situations in which bruising or injury may occur. Report any unusual bleeding, bruising, blood in stools, or dark, tarry stools to your doctor.
- Pyrimethamine/sulfadoxine may cause increased sensitivity to the sun. Avoid exposure to the sun, sunlamps, or tanning booths until you know how you react to pyrimethamine/sulfadoxine. Use a sunscreen or wear protective clothing if you must be outside for a prolonged period.
- Diabetes patients - Pyrimethamine/sulfadoxine may cause low blood sugar (eg, increased heartbeat, headache, chills, sweating, tremor, increased hunger, changes in vision, nervousness, weakness, dizziness, drowsiness, fainting). It is a good habit to carry glucose tablets or gel to treat low blood sugar. If you do not have a reliable source of glucose available, eat a quick source of sugar such as table sugar, honey, or candy, or drink a glass of orange juice or nondiet soda to quickly raise your blood sugar level. Tell your doctor immediately about the reaction. To prevent hypoglycemia, eat meals on a regular schedule and do not skip meals.
- LAB TESTS, including complete blood cell counts and liver and kidney function tests, may be performed to monitor your progress or to check for side effects. Be sure to keep all doctor and lab appointments.
- Use pyrimethamine/sulfadoxine with caution in the ELDERLY because they may be more sensitive to its effects.
- Pyrimethamine/sulfadoxine is not recommended for use in CHILDREN younger than 2 months of age. Safety and effectiveness in this age group have not been confirmed.
- If you are traveling to an area where malaria is common, avoid becoming pregnant while using pyrimethamine/sulfadoxine and for 3 months after the last dose. Talk with your doctor about using effective contraception.
- PREGNANCY and BREAST-FEEDING: Pyrimethamine/sulfadoxine may cause harm to the fetus. Avoid becoming pregnant while taking pyrimethamine/sulfadoxine. If you think you may be pregnant, discuss with your doctor the benefits and risks of using pyrimethamine/sulfadoxine during pregnancy. Pyrimethamine/sulfadoxine is excreted in breast milk. Do not breast-feed while taking pyrimethamine/sulfadoxine.
Possible side effects of pyrimethamine/ sulfadoxine:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Diarrhea; dizziness; headache; nausea; vomiting.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); cough; dark urine; decreased urination; depression; hallucinations; joint pain; lack of coordination; persistent sore throat, fever, or chills; red, swollen, or blistered skin; ringing in the ears; seizures; shortness of breath; sores on the mouth or lips; stomach pain; swelling or stinging of the tongue; tingling or numbness of the skin; unusual bruising or bleeding; unusual tiredness or weakness; yellowing of the skin or eyes.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include chills; crystals in the urine; loss of appetite; seizures; shaking; swelling of the tongue; vomiting.Proper storage of pyrimethamine/sulfadoxine:
Store pyrimethamine/sulfadoxine at room temperature, between 68 and 77 degrees F (20 and 25 degrees C). Brief storage at temperatures between 59 and 86 degrees F (15 and 30 degrees C) is permitted. Store away from heat, moisture, and light. Do not store in the bathroom. Keep pyrimethamine/sulfadoxine out of the reach of children and away from pets.
- If you have any questions about pyrimethamine/sulfadoxine, please talk with your doctor, pharmacist, or other health care provider.
- Pyrimethamine/sulfadoxine is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
This information is a summary only. It does not contain all information about pyrimethamine/sulfadoxine. If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.