Trimethoprim

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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.

Warning

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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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.

Precautions

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.

Instructions

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.

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.

Side Effects

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

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

pale skin, easy bruising or bleeding;
fever, chills, sore throat, flu symptoms; or
severe blistering, peeling, and red skin rash.

Less serious side effects may include:

nausea, vomiting;
sore or swollen tongue; or
mild itching or skin rash.

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.

Interactions

Tell your doctor about all other medications you use, especially phenytoin (Dilantin).

This list is not complete and there may be other drugs that can interact with trimethoprim. Tell your doctor about all your prescription and over-the-counter medications, vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start a new medication without telling your doctor.

Disclaimer

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.