PRECAUTIONS: Before taking trimethoprim, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: a certain type of anemia (due to folate deficiency), kidney disease, liver disease, vitamin deficiency (folate or folic acid), blood disorders (such as bone marrow suppression, G6PD deficiency), mineral imbalances (such as high level of potassium or low level of sodium in the blood).This medication may make you more sensitive to the sun. Avoid prolonged sun exposure, tanning booths, and sunlamps. Use a sunscreen and wear protective clothing when outdoors.If you have diabetes, this product may affect your blood sugar levels. Check your blood sugar levels regularly as directed by your doctor. Tell your doctor immediately if you have symptoms of low blood sugar (see Side Effects section). Your doctor may need to adjust your diabetes medication, exercise program, or diet.Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).Older adults may be more sensitive to the side effects of this drug, especially mineral imbalance (high potassium blood level) and allergic reactions.This medication is not recommended for use during pregnancy. It may harm an unborn baby. Consult your doctor for more details. This medication may lower your folic acid levels, increasing the risk of spinal cord defects. Therefore, check with your doctor to make sure you are taking enough folic acid.Trimethoprim passes into breast milk. While there have been no reports of harm to nursing infants, consult your doctor before breast-feeding.
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