trimethoprim, Trimpex (Discontinued Brand), Proloprim (Discontinued Brand), Primsol (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

SIDE EFFECTS: The most common side effects associated with trimethoprim are gastrointestinal. They include loss of appetite, nausea, vomiting, diarrhea, abdominal pain, abnormal taste, and swelling of the tongue. Taking trimethoprim with food may reduce some of these side effects. Trimethoprim may cause anemia due to a deficiency of folic acid. The anemia usually is mild and resolves when the trimethoprim is stopped. Patients who are folate-deficient, such as malnourished, alcoholic, geriatric, or pregnant patients, may be at greater risk for developing anemia with trimethoprim. Warning signs of anemia include white or bluish fingernails and unusual tiredness and weakness. Prolonged therapy can result in low platelet counts, low white blood cell counts, and other toxic effects on the blood cells. The most common side effects related to the skin are rash and itching. Rarely, the rash can progress to peeling or blistering. Some patients have photosensitivity reactions, that is, they develop skin rashes on parts of their body that are exposed to the sun.

Reference: FDA Prescribing Information


Last Editorial Review: 1/4/2012



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