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Cotrim

Generic Name: sulfamethoxazole and trimethoprim (sul fa meth OX a zole and trye METH oh prim)
Brand Names: Bactrim, Cotrim, Septra, Sulfatrim Pediatric

Medically reviewed by Drugs.com. Last updated on Nov 2, 2020.

What is Cotrim?

Cotrim is an antibiotic combination containing sulfamethoxazole and trimethoprim and it works by killing sensitive bacteria. Both ingredients are antibiotics that treat different types of infection caused by bacteria.

Cotrim is used to treat ear infections, urinary tract infections, bronchitis, traveler's diarrhea, and Pneumocystis carinii pneumonia.

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

Warnings

You should not use Cotrim if you are allergic to sulfamethoxazole or trimethoprim, if you are pregnant or breast-feeding, or if you have anemia (lack of red blood cells) caused by folic acid deficiency.

Before using Cotrim, tell your doctor if you have kidney or liver disease, a folic acid deficiency, asthma or severe allergies, AIDS, a glucose-6-phosphate dehydrogenase deficiency (G6PD deficiency), or if you are malnourished.

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

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or has blood in it, call your doctor. Do not use any medicine to stop the diarrhea unless your doctor has told you to.

Avoid exposure to sunlight, sunlamps, or tanning beds. Cotrim can make your skin more sensitive to sunlight, and a sunburn may result. Wear protective clothing and use sunscreen (SPF 15 or higher) when you are outdoors.

Before taking this medicine

You should not use Cotrim if you are allergic to sulfamethoxazole or trimethoprim, if you are pregnant or breast-feeding, or if you have anemia (lack of red blood cells) caused by folic acid deficiency.

If you have certain conditions, you may need a dose adjustment or special tests to safely use this medication. Before using Cotrim, tell your doctor if you have:

  • kidney or liver disease;
  • a folic acid deficiency;

  • asthma or severe allergies;

  • AIDS;

  • a glucose-6-phosphate dehydrogenase deficiency (G6PD deficiency); or

  • if you are malnourished.

Do not use Cotrim if you are pregnant. This medicine could harm the unborn baby or cause birth defects.

Do not use Cotrim if you are breast-feeding a baby. Sulfamethoxazole and trimethoprim can pass into breast milk and may harm a nursing baby.

Do not give Cotrim to a child younger than 2 months old. Older adults may be more likely to have side effects while taking this medication.

How should I take Cotrim?

Take Cotrim 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 Cotrim for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Cotrim will not treat a viral infection such as the common cold or flu. Drink plenty of fluids to prevent kidney stones while you are taking trimethoprim and sulfamethoxazole. Store the tablets and liquid at room temperature away from moisture, heat, and light.

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 can cause dizziness, drowsiness, nausea, vomiting, loss of appetite, stomach pain, headache, yellowing of your skin or eyes, blood in your urine, fever, confusion, or fainting.

What should I avoid?

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or has blood in it, call your doctor. Do not use any medicine to stop the diarrhea unless your doctor has told you to.

Avoid exposure to sunlight, sunlamps, or tanning beds. Cotrim can make your skin more sensitive to sunlight, and a sunburn may result. Wear protective clothing and use sunscreen (SPF 15 or higher) when you are outdoors.

Cotrim 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.

Seek medical treatment if you have a serious drug reaction that can affect many parts of your body. Symptoms may include: skin rash, fever, swollen glands, muscle aches, severe weakness, unusual bruising, or yellowing of your skin or eyes.

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

  • severe stomach pain, diarrhea that is watery or bloody (even if it occurs months after your last dose);

  • a skin rash, no matter how mild;

  • yellowing of your skin or eyes;

  • a seizure;

  • new or unusual joint pain;

  • increased or decreased urination;

  • swelling, bruising, or irritation around the IV needle;

  • increased thirst, dry mouth, fruity breath odor;

  • an electrolyte imbalance - headache, confusion, weakness, slurred speech, tingly feeling, chest pain, irregular heartbeats, loss of coordination or movement, feeling unsteady, vomiting; or

  • low blood cell counts - fever, chills, mouth sores, skin sores, easy bruising, unusual bleeding, pale skin, cold hands and feet, feeling light-headed or short of breath.

Common side effects may include:

  • nausea, vomiting, loss of appetite; or

  • skin rash.

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

What other drugs will affect Cotrim?

You may need more frequent check- ups or medical tests if you also use medicine to treat depression, diabetes, seizures, or HIV.

Tell your doctor about all your current medicines. Many drugs can affect sulfamethoxazole and trimethoprim, especially:

  • amantadine, cyclosporine, indomethacin, leucovorin, methotrexate, pyrimethamine;

  • an "ACE inhibitor" heart or blood presure medication (benazepril, enalapril, lisinopril, quinapril, ramipril, and others); or

  • a diuretic or "water pill" (chlorthalidone, hydrochlorothiazide, and others).

This list is not complete and there may be other drugs that can interact with Cotrim. 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.

Copyright 1996-2021 Cerner Multum, Inc. Version: 10.01.

Frequently asked questions

Further information

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

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.