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sulfisoxazole

Generic name: sulfisoxazole [ sul-fi-SOX-a-zole ]
Brand names: Gantrisin, Gantrisin Pediatric, Truxazole
Drug class: Sulfonamides

What is sulfisoxazole?

Sulfisoxazole is a sulfonamide ("sulfa") antibiotic that helps keep bacteria from growing in your body.

Sulfisoxazole is used to treat or prevent many different types of infections caused by bacteria, such as bladder infections, ear infections, or meningitis.

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

What is the most important information I should know about sulfisoxazole?

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

Do not share this medication with another person, even if they have the same symptoms you have.

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, stop taking sulfisoxazole and call your doctor. Do not use anti-diarrhea medicine unless your doctor tells you to.

What should I discuss with my health care provider before taking sulfisoxazole?

You should not use this medication if you are allergic to sulfisoxazole or to any other sulfa drugs such as Azulfidine, Bactrim, Cotrim, Septra, or Sulfazine. Women who are in late pregnancy or are breast-feeding should not take sulfisoxazole.

To make sure you can safely take sulfisoxazole, tell your doctor if you have any of these other conditions:

FDA pregnancy category C. It is not known whether sulfisoxazole will harm an unborn baby. Sulfisoxazole can cause jaundice (yellowing of the skin or eyes) and other problems in a newborn if the mother has taken this medication late in pregnancy. Tell your doctor if you are pregnant or plan to become pregnant while using this medication.

Sulfisoxazole can pass into breast milk and may harm a nursing baby. You should not breast-feed while you are taking sulfisoxazole, especially if your baby is younger than 2 months old.

Do not give this medicine to a child younger than 2 months old without the advice of a doctor.

How should I take sulfisoxazole?

Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

You may take sulfisoxazole with or without food.

Shake the oral suspension (liquid) well just before you measure a dose. Measure the liquid with a special dose-measuring spoon or medicine cup, not with a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

While you are taking sulfisoxazole, drink 6 to 8 glasses of water each day. This will help prevent kidney stones or crystals in the urine.

To be sure this medication is helping your condition, your blood may need to be tested often. Visit your doctor regularly.

If you need surgery, tell the surgeon ahead of time that you are using sulfisoxazole. You may need to stop using the medicine for a short time.

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

Do not share this medication with another person, even if they have the same symptoms you have.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include headache, drowsiness, nausea, vomiting, stomach pain, loss of appetite, fever, blood in your urine, pale skin, easy bruising or bleeding, flu symptoms, feeling light-headed, or fainting.

What should I avoid while taking sulfisoxazole?

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, stop taking sulfisoxazole and call your doctor. Do not use anti-diarrhea medicine unless your doctor tells you to.

Sulfisoxazole may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Avoid exposure to sunlight or tanning beds. Sulfisoxazole can make you sunburn more easily. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.

Sulfisoxazole 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.

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

Less serious side effects may include:

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.

Sulfisoxazole dosing information

Usual Adult Dose for Cystitis:

1 to 2 g orally every 6 hours for 3 to 7 days

Usual Adult Dose for Inclusion Conjunctivitis:

1 to 2 g orally every 6 hours for 21 days

Usual Adult Dose for Trachoma:

1 to 2 g orally every 6 hours for 21 days

Usual Adult Dose for Malaria:

2 g orally every 6 hours for 7 to 10 days; used only as adjunctive therapy in chloroquine-resistant Plasmodium falciparum

Usual Adult Dose for Nocardiosis:

2 g orally every 4 to 6 hours for at least 6 months
Immunocompromised patients may require up to 1 year or longer of treatment.

Usual Adult Dose for Otitis Media:

2 g orally every 6 hours for 10 to 14 days

Usual Adult Dose for Pelvic Inflammatory Disease:

500 mg orally every 6 hours for 21 days
Use in combination with ceftriaxone.

Usual Adult Dose for Pyelonephritis:

2 g orally every 6 hours for 14 days

Usual Adult Dose for Toxoplasmosis:

2 g orally every 6 hours with pyrimethamine 75 mg one time followed by 25 mg orally once a day
Folinic acid 3 to 9 mg orally 2 to 3 times a week is recommended to prevent bone marrow toxicity. Therapy should be continued for 2 to 4 months.

Usual Adult Dose for Meningitis -- Meningococcal:

2 g orally every 6 hours
Therapy should be continued for approximately 14 days, depending on the nature and severity of the infection.

Usual Adult Dose for Meningitis -- Haemophilus influenzae:

2 g orally every 6 hours
Therapy should be continued for approximately 14 days, depending on the nature and severity of the infection.

Usual Adult Dose for Chancroid:

2 g orally every 6 hours for approximately 7 days, depending on the nature and severity of the infection

The patient's sexual partner(s) should be evaluated. It is wise to also culture for gonococcus and to screen for syphilis.

Sulfisoxazole is not considered a drug of choice and is no longer recommended by the Centers for Disease Control and Prevention (CDC) to treat chancroid.

Usual Pediatric Dose for Bacterial Infection:

2 months or older: 75 mg/kg orally for 1 dose, followed by 120 to 150 mg/kg/day in divided doses every 4 to 6 hours
Maximum dose: 6 g/day

Usual Pediatric Dose for Chlamydia Infection:

2 months or older: 100 mg/kg/day orally in divided doses every 6 hours
Maximum dose: 2 g/day

Usual Pediatric Dose for Toxoplasmosis:

Congenital: Initial loading dose: 1/2 of the 24 hour dose
Maintenance dose: 150 mg/kg/day or 4 g/m2/day orally in 4 to 6 divided doses; used in conjunction with pyrimethamine
Maximum dose: 6 g/day

Usual Pediatric Dose for Pelvic Inflammatory Disease:

2 months or older: 100 mg/kg/day orally in divided doses every 6 hours; recommended to be used in combination with ceftriaxone

What other drugs will affect sulfisoxazole?

Tell your doctor about all other medicines you use, especially:

This list is not complete and other drugs may interact with sulfisoxazole. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

Further information

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

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