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Medications and Drugs

Brand Names: Primsol

Generic Name: trimethoprim (Pronunciation: trye METH oh prim)

What is trimethoprim (Primsol)?

Trimethoprim is an antibiotic that fights bacteria in the body.

Trimethoprim is used to treat bladder or kidney infections, or ear infections caused by certain bacteria.

Trimethoprim may also be used for purposes not listed in this medication guide.

Trimethoprim 100 mg-BIO

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Trimethoprim 100 mg-TEV

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Trimethoprim 100 mg-WAT

oval, white, imprinted with DAN DAN, 5571

What are the possible side effects of trimethoprim (Primsol)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have a serious side effect such as:

  • fever, chills, body aches, flu symptoms, sores in your mouth and throat;
  • pale skin, easy bruising, unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin;
  • high potassium (slow heart rate, weak pulse, muscle weakness, tingly feeling); or
  • severe headache with muscle cramps, confusion, weakness, loss of coordination, feeling unsteady, and weak or shallow breathing.

Other common side effects may include:

  • stomach pain, vomiting, diarrhea;
  • sore or swollen tongue; or
  • mild itching or skin rash.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about trimethoprim (Primsol)?

You should not use trimethoprim if you are allergic to it, or if you have a certain type of anemia caused by a folate (folic acid) deficiency.

Before using trimethoprim, tell your doctor if you have kidney disease, liver disease, or a folic acid deficiency.

Take this medicine for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Skipping doses may also increase your risk of further infection that is resistant to antibiotics. Trimethoprim will not treat a viral infection such as the common cold or flu.

Avoid exposure to sunlight or tanning beds. Trimethoprim can make you sunburn more easily. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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