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

You should not use this medication if you are allergic to trimethoprim, or if you have any type of anemia (lack of red blood cells).

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

Take this medication for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Trimethoprim will not treat a viral infection such as the common cold or flu. Avoid exposure to sunlight or artificial UV rays (sunlamps or tanning beds). Trimethoprim can make your skin more sensitive to sunlight and sunburn may result. Use a sunscreen (minimum SPF 15) and wear protective clothing if you must be out in the sun.

What is trimethoprim?

Trimethoprim is an antibiotic that fights bacteria in the body.

Trimethoprim is used to treat bladder infection caused by certain bacteria.

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

What should I discuss with my healthcare provider before taking trimethoprim?

You should not use this medication if you are allergic to trimethoprim, or have certain conditions. Be sure your doctor knows if you have any type of anemia (lack of red blood cells).

Before using trimethoprim, tell your doctor if you are allergic to any drugs, or if you have:

• kidney disease;

• liver disease; or

• a folate (folic acid) deficiency.

If you have any of these conditions, you may need a dose adjustment or special tests to safely use trimethoprim.

FDA pregnancy category C. This medication may be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment. Trimethoprim can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

How should I take trimethoprim?

Take this medication exactly as prescribed by your doctor. Do not take it in larger amounts or for longer than recommended. Follow the directions on your prescription label.

Take your medicine with a full glass of water.

Measure liquid medicine with a special dose-measuring spoon or cup, not a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

Take this medication for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Trimethoprim will not treat a viral infection such as the common cold or flu.

This medication can cause you to have unusual results with certain medical tests. Tell any doctor who treats you that you are using trimethoprim.

Store trimethoprim at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. If it is almost time for your next dose, wait until then to take the medicine and skip the missed dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention if you think you have used too much of this medicine.

Overdose symptoms may include nausea, vomiting, dizziness, headache, confusion, weakness, or flu symptoms.

What should I avoid while taking trimethoprim?

Avoid exposure to sunlight or artificial UV rays (sunlamps or tanning beds). Trimethoprim can make your skin more sensitive to sunlight and sunburn may result. Use a sunscreen (minimum SPF 15) and wear protective clothing if you must be out in the sun.