Septra

Generic Name: Sulfamethoxazole

  • What is Septra?

    Septra is an antibacterial agent used to treat a wide variety of bacterial infections, including urinary tract infections, middle ear infections, bronchitis, intestinal infection (shigellosis), pneumonia, and traveler's diarrhea. Septra can also be used to prevent pneumonia.

  • What is the most important information I should know about Septra?

    Septra may cause serious liver problems, blood disorders such as anemia, a severe skin rash, shortness of breath, cough, sore throat, fever, and joint pain. If you experience any of these reactions while taking Septra, stop taking it and contact your doctor immediately. These may be signs of a rare, but serious, allergic reaction.

    Mild diarrhea is common with antibiotic use. However, a more serious form of diarrhea, although rare, may occur. This condition can range in severity from mild diarrhea to a severe inflammation of the large intestine. Patients may develop watery and bloody stools even as late as 2 or more months after having taken the last dose of the antibiotic. Contact your doctor right away if this condition is suspected. Do not treat the diarrhea without first checking with your doctor.

    Septra should only be used to treat bacterial infections. It will not treat viral infections like the common cold.

    Although it is common to feel better early in the course of therapy, you should use this medication exactly as directed by your physician for the entire length of time prescribed. Complete the full course of therapy and do not skip any doses.

    Septra may make it more difficult for your blood to clot. If you notice any unusual bruising, bleeding, or rash, stop taking Septra and contact your doctor immediately. You may require frequent blood tests while on Septra, especially if you have kidney disease.

    Patients with AIDS are more likely to experience certain side effects.

  • Who should not take Septra?

    You should not take Septra if you are allergic to trimethoprim or sulfonamide antibiotics, or if you've experienced an allergic reaction to Septra before. Do not take Septra if you have a condition called megaloblastic anemia due to folate deficiency. Also, do not use Septra if you are near the end of your pregnancy (at term) or breastfeeding. Septra should not be used in children less than 2 months old.

  • What should I tell my doctor before I take the first dose of Septra?

    Tell your doctor about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Septra. Also talk to your doctor about your complete medical history, especially if have a drug allergy to sulfa drugs, liver or kidney disease, a blood disorder, if you are pregnant or breastfeeding, if you have asthma or severe allergies, anemia due to folate deficiency, AIDS, or if you are malnourished.

  • What is the usual dosage?

    The information below is based on the dosage guidelines your doctor uses. Depending on your condition and medical history, your doctor may prescribe a different regimen. Do not change the dosage or stop taking your medication without your doctor's approval.

    Acute Worsening of Chronic Bronchitis

    Adults: The usual dosage is one Septra DS (double strength) tablet or two Septra tablets, or four teaspoonfuls of Septra suspension, every 12 hours for 14 days.

    Middle Ear Infections (Acute Otitis Media)

    Children ≥ 2 months: Your doctor will prescribe the appropriate dosage based on your child's condition, age, and weight. The usual dosage is given in two divided doses every 12 hours for 10 days.

    Pneumonia

    Adults and Children ≥ 2 months: Your doctor will prescribe the appropriate dosage for you or your child based on age and weight. The usual dosage is given in equally divided doses every 6 hours for 14-21 days.

    Prevention of Pneumonia

    Adults: The usual dosage is one Septra DS (double strength) tablet daily.

    Children ≥ 2 months: Your doctor will prescribe the appropriate dosage based on your child's condition, age, and weight. The usual dosage is given in equally divided doses twice a day, on 3 consecutive days per week.

    Traveler's Diarrhea

    Adults: The usual dosage is one Septra DS (double strength) tablet, or two Septra tablets, or four teaspoonfuls of Septra suspension every 12 hours for 5 days.

    Urinary Tract Infections and Bacterial Infection of the Intestines (Shigellosis)

    Adults: The usual dosage for a urinary tract infection is one Septra DS (double strength) tablet or two Septra tablets, or four teaspoonfuls of Septra suspension, every 12 hours for 10-14 days. An identical dosage is used for 5 days in the treatment of shigellosis.

    Children ≥ 2 months: Your doctor will prescribe the appropriate dosage based on your child's condition, age, and weight. The usual dosage for a urinary tract infection is given in two divided doses every 12 hours for 10 days. An identical dosage is used for 5 days in the treatment of shigellosis.

  • How should I take Septra?

    Take this medication for the entire length of time prescribed by your doctor. Skipping doses or not completing the full course of therapy may decrease the drug's effectiveness, increase the chances for bacterial resistance, and will not be treatable by Septra or other antibacterial drugs in the future.

    While taking Septra, it's important to drink a lot of water in order to prevent kidney stones, unless told otherwise by your doctor.

    If you are using the suspension, make sure to shake it first and measure the liquid with a special dose-measuring spoon or cup.

  • What should I avoid while taking Septra?

    Avoid skipping doses or not completing the full course of therapy. 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 those cases.

    Do not use any medicine to stop diarrhea without your doctor's approval.

    Do not forget to drink plenty of water while taking Septra.

  • What are possible food and drug interactions associated with Septra?

    If Septra is used with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining Septra with the following: ACE inhibitors (such as enalapril and ramipril), blood-thinning medications such as warfarin, diuretics (such as hydrochlorothiazide), methotrexate, and phenytoin.

  • What are the possible side effects of Septra?

    Side effects cannot be anticipated. If any develop or change in intensity, tell your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking this drug.

    Side effects may include: diarrhea, nausea, vomiting, loss of appetite, skin rash, hives, anemia, liver/kidney problems, trouble sleeping

  • Can I receive Septra if I am pregnant or breastfeeding?

    Septra should not be used near the end of your pregnancy (at term). Because Septra may interfere with folic acid metabolism, it should be used earlier during pregnancy only if the potential benefit outweighs the potential risk. If you are pregnant or plan to become pregnant, inform your doctor immediately. Since Septra may appear in breast milk, you should not use it if you are breastfeeding.

  • What should I do if I miss a dose of Septra?

    If you miss a dose of Septra, take the missed dose as soon as you remember it. However, if it almost time for your next dose, skip the one you missed and return to your regular dosing schedule. Do not take two doses at once. If you are unsure, ask your doctor or pharmacist for advice.

  • How should I store Septra?

    Store Septra at room temperature in a well-closed container away from light.

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