
What is Septra?
Septra (sulfamethoxazole / trimethoprim) is used to treat certain bacterial infections. Septra treats infections like:
- Urinary tract infections (bladder infections)
- Ear infections in children
- Lung infections in adults with chronic bronchitis
- Certain bacteria cause traveler’s diarrhea
- Stomach infections caused by Shigella bacteria
- Lung infection called Pneumocystis jirovecii pneumonia, especially in people with weak immune systems
Septra does not work for treating colds or the flu. It only works for infections caused by certain bacteria.
Take this medication exactly as your doctor prescribes it.
How Does Septra Work?
Septra works by inhibiting the growth of bacteria. It contains two main ingredients: trimethoprim and sulfamethoxazole. These two work together to block the steps bacteria use to make folic acid. Bacteria need folic acid to grow and stay alive.
When Septra blocks this process, the bacteria stop multiplying and eventually die.
After you take Septra by mouth, it quickly goes into your blood. There, the two active parts start fighting the infection. They move through your body and help kill the bacteria causing the illness. Later, your body breaks them down and removes them through urine.
Septra Dosage Information and Administration
Doctors prescribe Septra to treat various bacterial infections. Your age, weight, and type of infection determine the right dose. Septra is available in various strengths and forms, including tablets and liquid suspension.
Avoid giving Septra to babies younger than two months. Children and adults usually take the dose every 12 hours.
Some infections require treatment for 5 to 14 days, while others need longer use or specific dosing schedules.
Dosage Form and Strengths of Septra
- Septra tablets: 80 mg trimethoprim and 400 mg sulfamethoxazole
- Septra DS (double strength) tablets: 160 mg trimethoprim and 800 mg sulfamethoxazole
- Septra oral suspension (cherry or grape flavor): 40 mg trimethoprim and 200 mg sulfamethoxazole in each 5 mL (1 teaspoon)
How to Take Septra?
- Take Septra exactly as directed by your doctor.
- Use a measuring spoon or cup for liquid forms.
- Take your dose every 12 hours unless told otherwise.
- Drink lots of water while using Septra to help protect your kidneys.
- Finish the full number of days even if you feel better.
- Do not double your dose if you forget to take it.
- If you overdose, get help right away.
Recommended Dosage by Condition or Population
Adults with Urinary Tract Infections or Shigellosis
Adults usually take one double-strength tablet, two regular tablets, or four teaspoons (20 mL) of the suspension every 12 hours.
Patients take this for 10 to 14 days to treat urinary infections. They take the same dose for 5 days to treat shigellosis.
Children with Urinary Tract Infections, Otitis Media, or Shigellosis
Children take Septra based on their weight. The dose is 8 mg/kg of trimethoprim and 40 mg/kg of sulfamethoxazole, administered in two divided doses every 12 hours.
For example:
- A child weighing 10 kg (22 lb) takes 5 mL every 12 hours
- A child weighing 20 kg (44 lb) takes 10 mL or one tablet every 12 hours
Doctors usually treat this condition for 10 days in cases of infection and 5 days in cases of shigellosis.
Adults with Chronic Bronchitis Flare-Ups
Adults take the same standard adult dose (1 DS tablet or 20 mL) every 12 hours for 14 days.
Adults with Travelers’ Diarrhea
The usual dose is 1 DS tablet, two tablets, or 20 mL of suspension every 12 hours for 5 days.
Pneumocystis jirovecii Pneumonia (Treatment)
Doctors administer 15 to 20 mg/kg of trimethoprim and 75 to 100 mg/kg of sulfamethoxazole per day to adults and children. They divide this into four doses, given every 6 hours, for 14 to 21 days.
The dose depends on body weight. For example:
- A child weighing 24 kg takes 15 mL every 6 hours
- An adult weighing 80 kg takes 50 mL or 2.5 DS tablets every 6 hours
Pneumocystis jirovecii Pneumonia (Prevention)
- Adults take 1 DS tablet once a day.
- Children take one hundred fifty milligrams per square meter of trimethoprim and seven hundred fifty milligrams per square meter of sulfamethoxazole each day. They take these doses in two parts, twice a week for three days each.
People with Kidney Problems
- If kidney function is normal, use the full dose.
- If kidney function is mildly reduced, use half the dose.
- If kidney function is very low (creatinine clearance below 15 mL/min), Septra should not be used.
Side Effects of Septra
Others may experience more serious problems, such as breathing trouble, yellow skin, or changes in how often they urinate.
Common Side Effects
These are the most common side effects people may feel when using Septra:
- Nausea
- Vomiting
- Loss of appetite
- Skin rash or itching
- Headache
- Feeling tired
- Diarrhea
- Mild stomach pain
Severe Side Effects
- Rash with blisters or skin peeling
- Fever, sore throat, or burning eyes
- Swelling of the face, lips, or throat
- Trouble breathing or chest pain
- Yellowing of the skin or eyes
- Severe stomach pain or bloody diarrhea
- Unusual tiredness or pale skin
- Bruising or bleeding easily
- Seizures or feeling confused
- New joint or muscle pain
- Little or no urination
- Irregular heartbeat or chest discomfort
- Feeling dizzy or faint
- Cold hands and feet
Warnings and Precautions for Septra
Septra can help fight many types of bacterial infections, but it is important to be aware of certain risks before using it.
Some people may have serious reactions, especially those with health problems or those who are pregnant.
Septra can also affect your blood, kidneys, liver, and lungs. It is important to follow your doctor’s directions and report any unusual symptoms.
- Septra may harm an unborn baby if taken during pregnancy. Consult your doctor if you are pregnant or planning to become pregnant.
- Serious allergic reactions can happen. These include skin rashes, breathing problems, or shock. Stop taking Septra and seek help immediately if you experience any of these signs.
- Some people may get serious lung problems after using Septra. This can cause breathing trouble and may require hospital care.
- Septra may cause serious skin problems, including rashes with blisters, peeling, and pain. These may be signs of life-threatening conditions.
- If you have had Septra recently and start it again, you may have a sudden severe reaction with fever, confusion, or very low blood pressure.
- Signs such as fever, sore throat, rash, yellowing of the skin, or unusual bruising may be early warnings of a potentially dangerous reaction. Get medical help right away.
- Septra may decrease blood platelet levels, which can lead to bleeding or bruising. This condition usually goes away after stopping Septra.
- Septra does not treat certain types of strep infections and should not be used to prevent complications, such as rheumatic fever.
- Diarrhea caused by a bacteria called C. difficile can happen during or after using Septra. This type of diarrhea can be serious and may last weeks.
- Using Septra with leucovorin in people with HIV who have a lung infection reduces its effectiveness and increases death rates. Avoid this drug combination.
- Using Septra without a clear bacterial infection may cause bacteria to become stronger and harder to treat in the future.
- People with poor nutrition, liver problems, kidney disease, or certain other conditions may be more likely to develop side effects. These patients should use Septra carefully.
- People with low folate levels, like the elderly or those with alcohol problems, may have a higher risk of bad reactions.
- Septra can cause red blood cell breakdown in people with a rare condition called G6PD deficiency. This can be serious.
- Low blood sugar can happen even in people who do not have diabetes. This risk is higher in people with poor health or kidney or liver problems.
- Septra may change how your body processes phenylalanine, but this is not a concern for most people.
- People with thyroid issues or porphyria, a rare blood condition, should use Septra with caution.
- People with HIV may have more side effects from Septra, especially fever, rash, or changes in blood tests. Reactions are often milder when Septra is used to prevent infections rather than to treat them.
- Taking Septra and leucovorin at the same time in people with HIV is not recommended.
- Septra can cause high potassium levels, especially in people with kidney problems or those taking other drugs that raise potassium.
- Septra can also cause low sodium levels, which can lead to confusion, weakness, and serious health problems.
- Drinking enough water while using Septra can help prevent crystals from forming in the urine, which may hurt the kidneys.
- Always finish the full course of Septra even if you feel better early. Skipping doses or stopping treatment too soon may cause the infection to return or become more difficult to treat.
Septra Drug Interactions
Septra can interact with many other drugs, which may increase the chance of side effects or make other treatments less effective.
Tell your doctor about all the drugs, vitamins, or herbal products you use before starting Septra.
Some combinations should be avoided, and others may need close monitoring.
- warfarin
- phenytoin
- methotrexate
- cyclosporine
- digoxin
- indomethacin
- pyrimethamine
- tricyclic antidepressants
- oral diabetes drugs like glipizide, glyburide, metformin, pioglitazone, repaglinide, rosiglitazone
- amantadine
- ACE inhibitors like enalapril, lisinopril, ramipril
- zidovudine
- dofetilide
- procainamide
- Diuretics like hydrochlorothiazide, chlorthalidone
- leucovorin
- HIV treatments
- seizure medications
- over-the-counter pain relievers
- Herbal supplements and vitamins
Alternative Medications to Septra
If you cannot take Septra due to side effects, allergies, or drug interactions, there are other antibiotics your doctor may prescribe instead.
These alternatives can treat many of the same bacterial infections. The right one for you will depend on the type of infection and your overall health.
- Macrobid (nitrofurantoin)
- Cipro (ciprofloxacin)
- Amoxil (amoxicillin)
- Keflex (cephalexin)
- Levaquin (levofloxacin)
- Clindamycin
- Doxycycline
- Zithromax (azithromycin)
- Augmentin (amoxicillin and clavulanate)
- Monurol (fosfomycin)
Order Budget-Friendly Septra from Canada
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How to Order Septra Online?
- Search for Septra, choose your dosage, and click Buy to add it to your cart.
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Disclaimer
Pharma Giant provides medical information to help you better understand medications and medical conditions.This content is for informational use only and does not replace advice from a licensed medical practitioner. Consult your doctor or pharmacist before starting or changing any medication. All our partners follow strict safety standards set by their country’s health authorities to make sure you receive safe and high-quality medications.





