The originating document has been archived. We cannot confirm the completeness, accuracy and currency of the content.
Generic Name: sulfamethoxazole/trimethoprim (SUL-fa-meth-OX-a-zole/trye-METH-oh-prim)
Brand Name: Examples include Bactrim and Bactrim DS
Septra is used for:
Treating infections caused by certain bacteria. It is also used to prevent certain infections.
Septra is an antibiotic combination containing a sulfonamide antibiotic. It works by killing sensitive bacteria.
Do NOT use Septra if:
- you are allergic to any ingredient in Septra or to any other sulfonamide (sulfa) medicine (eg, glipizide, hydrochlorothiazide)
- you have a history of low blood platelet levels (immune thrombocytopenia) caused by trimethoprim or a sulfa medicine
- you have liver damage or severe kidney problems
- you have anemia caused by low levels of folate in the blood
- the patient is a child younger than 2 months old
- you are taking dofetilide or methenamine
Contact your doctor or health care provider right away if any of these apply to you.
Before using Septra:
Some medical conditions may interact with Septra. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have liver or kidney problems, certain blood problems (eg, anemia, porphyria), thyroid problems, asthma, glucose-6-phosphate dehydrogenase (G6PD) deficiency, or HIV infection
- if you have low levels of folate in the blood or are at risk for low blood folate levels (eg, you have alcoholism, you are elderly, you do not absorb nutrients from food properly, you are in a poor nutritional state, you are taking medicine for seizures)
- if you have a history of high blood potassium levels
Some MEDICINES MAY INTERACT with Septra. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Angiotensin-converting enzyme (ACE) inhibitors (eg, enalapril), diuretics (eg, hydrochlorothiazide), or indomethacin because they may increase the risk of Septra's side effects
- Anticoagulants (eg, warfarin) because the risk of bleeding may be increased
- Dofetilide because the risk of its side effects, including severe irregular heartbeat, may be increased by Septra
- Pyrimethamine because it is possible that a certain type of anemia may develop
- Methenamine because certain urinary problems may occur
- Amantadine, digoxin, hydantoins (eg, phenytoin), methotrexate, sulfones (eg, dapsone), or oral medicine for diabetes (eg, glipizide, metformin, pioglitazone) because the risk of their side effects may be increased by Septra
- Tricyclic antidepressants (eg, amitriptyline) because their effectiveness may be decreased by Septra
- Cyclosporine because its effectiveness may be decreased and the risk of kidney side effects may be increased
This may not be a complete list of all interactions that may occur. Ask your health care provider if Septra may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use Septra:
Use Septra as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Take Septra by mouth with or without food.
- Septra works best if it is taken at the same time(s) each day.
- Take Septra with a full glass of water (8 oz [240 mL]). Drinking extra fluids while you are taking Septra is recommended. Check with your doctor for instructions.
- To clear up your infection completely, take Septra for the full course of treatment. Keep taking it even if you feel better in a few days.
- If you are using Septra to prevent an infection, continue to take it even if you feel well. Do not miss any doses.
- If you miss a dose of Septra, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.
Ask your health care provider any questions you may have about how to use Septra.
Important safety information:
- Septra may cause you to become sunburned more easily. Avoid the sun, sunlamps, or tanning booths until you know how you react to Septra. Use a sunscreen or wear protective clothing if you must be outside for more than a short time.
- Mild diarrhea is common with antibiotic use. However, a more serious and sometimes fatal form of diarrhea (pseudomembranous colitis) may rarely occur. This may develop while you use the antibiotic or within several months after you stop using it. Contact your doctor right away if stomach pain or cramps, severe diarrhea, or bloody stools occur. Do not treat diarrhea without first checking with your doctor.
- Be sure to use Septra for the full course of treatment. If you do not, the medicine may not clear up your infection completely. The bacteria could also become less sensitive to this or other medicines. This could make the infection harder to treat in the future.
- Septra only works against bacteria; it does not treat viral infections (eg, the common cold).
- Long-term or repeated use of Septra may cause a second infection. Tell your doctor if signs of a second infection occur. Your medicine may need to be changed to treat this.
- A very bad skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis) may happen. It can cause very bad health problems that may not go away and sometimes death. Get medical help right away if you have signs like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in your mouth, throat, nose, or eyes.
- Severe and sometimes fatal liver problems have happened in patients taking Septra. Tell your doctor right away if you develop symptoms of liver problems (eg, dark urine; pale stools; severe or persistent nausea or vomiting, loss of appetite, or stomach pain; unusual tiredness; yellowing of skin or eyes).
- Serious and sometimes fatal blood problems may happen. Contact your doctor immediately if you develop fever, chills, or sore throat; joint pain; pale skin; unusual bruising or bleeding; or unusual tiredness or weakness.
- Septra may cause serious lung problems. Tell your doctor right away if you develop a cough, shortness of breath, or chest pain.
- Patients taking Septra to treat a certain type of pneumonia should avoid taking leucovorin. It may decrease Septra's effectiveness. Talk with your doctor if you are taking leucovorin.
- Do not receive a live vaccine (eg, measles, mumps) while you are taking Septra. Talk with your doctor before you receive any vaccine.
- Diabetes patients - Septra may affect your blood sugar. Check blood sugar levels closely. Ask your doctor before you change the dose of your diabetes medicine.
- Septra may interfere with certain lab tests. Be sure your doctor and lab personnel know you are taking Septra.
- Lab tests, including complete blood cell counts, blood potassium levels, and kidney function, may be performed while you use Septra. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
- Use Septra with caution in the ELDERLY; they may be more sensitive to its effects, especially severe skin reactions, bone marrow problems, or high blood potassium levels.
- Septra should not be used in CHILDREN younger than 2 months old; safety and effectiveness in these children have not been confirmed.
- PREGNANCY and BREAST-FEEDING: Septra may cause harm to the fetus. If you think you may be pregnant, contact your doctor. You will need to discuss the benefits and risks of using Septra while you are pregnant. Septra is found in breast milk. If you are or will be breast-feeding while you use Septra, check with your doctor. Discuss any possible risks to your baby.
Possible side effects of Septra:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Appetite loss; mild diarrhea; nausea; vomiting.
Severe allergic reactions (rash; hives; itching; difficulty breathing or swallowing; tightness in the chest; swelling of the mouth, face, lips, throat, or tongue; unusual hoarseness); bloody or black, tarry stools; change in the amount of urine produced; confusion; decreased urination; fast or irregular heartbeat; hallucinations; joint or muscle pain; lower back or flank pain; mental or mood changes (eg, depression); painful or stiff neck; purple patches under the skin; seizures; severe or persistent diarrhea; severe or persistent headache; severe or persistent nausea or vomiting; severe stomach or back pain (with or without nausea or vomiting); stomach cramps; swelling or soreness of the mouth or tongue; symptoms of low blood sugar (eg, increased sweating, weakness, tremors, dizziness, fainting, drowsiness, headache, chills, fast heartbeat, vision changes, increased hunger); vaginal irritation or discharge; vomit that looks like coffee grounds.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately.Proper storage of Septra:
Store Septra at room temperature, between 68 and 77 degrees F (20 and 25 degrees C). Store away from heat, moisture, and light. Keep in a tight, light-resistant container. Do not store in the bathroom. Keep Septra out of the reach of children and away from pets.
- If you have any questions about Septra, please talk with your doctor, pharmacist, or other health care provider.
- Septra is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- Check with your pharmacist about how to dispose of unused medicine.
This information should not be used to decide whether or not to take Septra or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about Septra. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Septra. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using Septra.