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Sulfamethoxazole, Trimethoprim Oral tablet

What is this medicine?

SULFAMETHOXAZOLE; TRIMETHOPRIM or SMX-TMP (suhl fuh meth OK suh zohl; trye METH oh prim) is a combination of a sulfonamide antibiotic and a second antibiotic, trimethoprim. It is used to treat or prevent certain kinds of bacterial infections. It will not work for colds, flu, or other viral infections.

How should I use this medicine?

Take this medicine by mouth with a full glass of water. Follow the directions on the prescription label. Take your medicine at regular intervals. Do not take it more often than directed. Do not skip doses or stop your medicine early.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed. This medicine has been used in children as young as 2 months of age.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • allergic reactions like skin rash or hives, swelling of the face, lips, or tongue

  • breathing problems

  • fever or chills, sore throat

  • irregular heartbeat, chest pain

  • joint or muscle pain

  • pain or difficulty passing urine

  • red pinpoint spots on skin

  • redness, blistering, peeling or loosening of the skin, including inside the mouth

  • unusual bleeding or bruising

  • unusually weak or tired

  • yellowing of the eyes or skin

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • diarrhea

  • dizziness

  • headache

  • loss of appetite

  • nausea, vomiting

  • nervousness

What may interact with this medicine?

Do not take this medicine with any of the following medications:

  • aminobenzoate potassium

  • dofetilide

  • metronidazole

This medicine may also interact with the following medications:

  • ACE inhibitors like benazepril, enalapril, lisinopril, and ramipril

  • cyclosporine

  • digoxin

  • diuretics

  • indomethacin

  • medicines for diabetes

  • methenamine

  • methotrexate

  • phenytoin

  • potassium supplements

  • pyrimethamine

  • sulfinpyrazone

  • tricyclic antidepressants

  • warfarin

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

Where should I keep my medicine?

Keep out of the reach of children.

Store at room temperature between 20 to 25 degrees C (68 to 77 degrees F). Protect from light. Throw away any unused medicine after the expiration date.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:

  • anemia

  • asthma

  • being treated with anticonvulsants

  • if you frequently drink alcohol containing drinks

  • kidney disease

  • liver disease

  • low level of folic acid or glucose-6-phosphate dehydrogenase

  • poor nutrition or malabsorption

  • porphyria

  • severe allergies

  • thyroid disorder

  • an unusual or allergic reaction to sulfamethoxazole, trimethoprim, sulfa drugs, other medicines, foods, dyes, or preservatives

  • pregnant or trying to get pregnant

  • breast-feeding

What should I watch for while using this medicine?

Tell your doctor or health care professional if your symptoms do not improve. Drink several glasses of water a day to reduce the risk of kidney problems.

Do not treat diarrhea with over the counter products. Contact your doctor if you have diarrhea that lasts more than 2 days or if it is severe and watery.

This medicine can make you more sensitive to the sun. Keep out of the sun. If you cannot avoid being in the sun, wear protective clothing and use a sunscreen. Do not use sun lamps or tanning beds/booths.