Trimethoprim

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

Trimethoprim may also be used for reasons not mentioned in this medication guide.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Measure liquid medicine carefully. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

Use trimethoprim for the full prescribed length of time, even if your symptoms quickly improve. Skipping doses can increase your risk of infection that is resistant to medication. This medicine will not treat a viral infection such as the flu or a common cold.

This medicine can affect the results of certain medical tests. Tell any doctor who treats you that you are taking trimethoprim.

Store at room temperature away from moisture, heat, and light.

You should not use trimethoprim if you have anemia due to a folate (folic acid) deficiency.

You should not use trimethoprim if you are allergic to it, or if you have:

• anemia (low red blood cells) caused by a folate (folic acid) deficiency.

Trimethoprim is not approved for use by anyone younger than 2 months old. Trimethoprim should not be used to treat an ear infection in a child younger than 6 months old.

Tell your doctor if you have ever had:

• a folate deficiency;
• liver or kidney disease; or
• a blood disorder.

Tell your doctor if you are pregnant. Trimethoprim can interfere with your body's ability to metabolize folic acid, which is important for the development of the unborn baby's brain and spinal cord.

It may not be safe to breastfeed while using this medicine. Ask your doctor about any risk.

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

Trimethoprim may cause serious side effects. Call your doctor right away if you have:

• severe stomach pain, diarrhea that is watery or bloody (even if it happens months after your last dose);
• pale, gray, or bluish skin;
• fever, weakness;
• sore or swollen tongue;
• easy bruising, purple or red spots under your skin;
• a skin rash, no matter how mild; or
• high potassium level--nausea, weakness, tingling feeling, chest pain, irregular heartbeats, loss of movement.

Common side effects of trimethoprim may include:

• vomiting, diarrhea, stomach pain;
• rash, itching; or
• swelling in your tongue.

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

Usual Adult Dose for Urinary Tract Infection:

100 mg orally every 12 hours or 200 mg orally every 24 hoursDuration of therapy: 10 daysUse: For the treatment of initial episodes of uncomplicated urinary tract infections due to susceptible strains of Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Enterobacter species, and coagulase-negative Staphylococcus species (including Staphylococcus saprophyticus)

Usual Pediatric Dose for Urinary Tract Infection:

12 years or older: 100 mg orally every 12 hours or 200 mg orally every 24 hoursDuration of therapy: 10 daysUse: For the treatment of initial episodes of uncomplicated urinary tract infections due to susceptible strains of E coli, P mirabilis, K pneumoniae, Enterobacter species, and coagulase-negative Staphylococcus species (including S saprophyticus)

Usual Pediatric Dose for Otitis Media:

6 months or older: 5 mg/kg orally every 12 hours for 10 daysMaximum dose: 200 mg/doseComments:-This drug is not indicated for prophylactic or prolonged use in otitis media at any age.-When infection with Moraxella catarrhalis suspected, use of alternative antimicrobial agents should be considered.Use: For the treatment of acute otitis media due to susceptible strains of Streptococcus pneumoniae and Haemophilus influenzae

Take the medicine as soon as you remember, but skip the missed dose if it's nearly time for your next dose. Do not take two doses at the same time.

Seek emergency medical help or call the Poison Help line at 1-800-222-1222.

Signs of an overdose may include nausea, vomiting, headache, dizziness, confusion, depression, fever, chills, or flu-like symptoms.

An overdose can happen slowly over time if your daily doses are too high.

Antibiotic medicines can lead to diarrhea, which might indicate a new infection. If you experience diarrhea that is watery or bloody, contact your doctor before taking anti-diarrhea medicine.

Other drugs may affect trimethoprim, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you begin or stop using.