This medication is a combination of two antibiotics: sulfamethoxazole and trimethoprim. It is used to treat a wide variety of bacterial infections (such as middle ear, urine, respiratory, and intestinal infections). It is also used to prevent and treat a certain type of pneumonia (pneumocystis-type).
This medication should not be used in children less than 2 months of age due to the risk of serious side effects.
This medication treats only certain types of infections. It will not work for viral infections (such as flu). Unnecessary use or misuse of any antibiotic can lead to its decreased effectiveness.
Take this medication by mouth, as directed by your doctor, with a full glass of water (8 ounces / 240 milliliters). If stomach upset occurs, take with food or milk. Drink plenty of fluids while taking this medication to lower the unlikely risk of kidney stones forming, unless your doctor advises you otherwise. Dosage is based on your medical condition and response to treatment.
Antibiotics work best when the amount of medicine in your body is kept at a constant level. Therefore, take this drug at evenly spaced intervals.
Continue to take this medication until the full prescribed amount is finished, even if symptoms disappear after a few days. Stopping it too early may allow bacteria to continue to grow, which may result in a relapse of the infection.
Tell your doctor if your condition persists or worsens.
Tell your doctor right away if you have any serious side effects, including: muscle weakness, mental/mood changes, blood in the urine, change in the amount of urine, extreme drowsiness, signs of low blood sugar (such as nervousness, shakiness, sweating, hunger).
This medication may rarely cause serious (possibly fatal) allergic reactions and other side effects such as a severe peeling skin rash (such as Stevens-Johnson syndrome), blood disorders (such as agranulocytosis, aplastic anemia), liver damage, or lung injury. If you notice any of the following, get medical help right away: skin rash/blisters, itching/swelling (especially of the face/tongue/throat), persistent sore throat or fever, paleness, joint pain/aches, persistent cough, trouble breathing, easy bleeding/bruising, yellowing eyes or skin, persistent nausea/vomiting, unusual fatigue, dark urine.
This medication may rarely cause a severe intestinal condition (Clostridium difficile-associated diarrhea) due to a type of resistant bacteria. This condition may occur during treatment or weeks to months after treatment has stopped. Tell your doctor right away if you develop: persistent diarrhea, abdominal or stomach pain/cramping, blood/mucus in your stool.
Do not use anti-diarrhea products or narcotic pain medications if you have any of these symptoms because these products may make them worse.
Use of this medication for prolonged or repeated periods may result in oral thrush or a new yeast infection. Contact your doctor if you notice white patches in your mouth, a change in vaginal discharge, or other new symptoms.
In the US -
Before taking sulfamethoxazole with trimethoprim, tell your doctor or pharmacist if you are allergic to sulfa medications or trimethoprim; 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: kidney disease, liver disease, certain blood disorders (such as porphyria, anemia due to folate vitamin deficiency), history of blood disorders caused by trimethoprim or sulfa medications, vitamin deficiency (folate or folic acid), severe allergies, asthma, decreased bone marrow function (bone marrow suppression), a certain metabolic disorder (G6PD deficiency), underactive thyroid, mineral imbalances (such as high level of potassium or low level of sodium in the blood).
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
This medication may make you more sensitive to the sun. Avoid prolonged sun exposure, tanning booths or 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 right away 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.
Older adults may be more sensitive to the side effects of this drug, especially skin reactions, blood disorders, easy bleeding/bruising, and a high potassium blood level.
Patients with AIDS may be more sensitive to the side effects of this drug, especially skin reactions, fever, and blood disorders.
This medication is not recommended for use during pregnancy especially near the expected delivery date because of possible harm to the unborn baby. Consult your doctor for more details.
This drug passes into breast milk. While there have been no reports of harm to healthy infants, this drug may have undesirable effects on infants who are ill or premature or have certain disorders (jaundice, high blood levels of bilirubin, G6PD deficiency). Therefore, breast-feeding is not recommended for infants with these conditions. Consult your doctor before breast-feeding.
Some products that may interact with this drug include: "blood thinners" (such as warfarin), cyclosporine, dofetilide, hydantoins (such as phenytoin), live vaccines, methenamine, methotrexate.
Although most antibiotics are unlikely to affect hormonal birth control such as pills, patch, or ring, a few antibiotics (such as rifampin, rifabutin) can decrease their effectiveness. This could result in pregnancy. If you use hormonal birth control, ask your doctor or pharmacist for more details.
This product may interfere with certain laboratory tests, possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this product.
If overdose is suspected, contact a poison control center or emergency room right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe nausea/vomiting/diarrhea, severe dizziness or drowsiness, mental/mood changes.
Do not share this medication with others.
This medication has been prescribed for your current condition only. Do not use it later for another infection unless told to do so by your doctor. A different medication may be necessary in that case.
If taking this medication for an extended period, laboratory and/or medical tests (such as complete blood count, kidney function tests, potassium blood level, cultures) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.
Information last revised October 2015. Copyright(c) 2015 First Databank, Inc.
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