Pronounced: BAC-trim Generic ingredients: Trimethoprim, Sulfamethoxazole
Other brand name: Septra
Why is this drug prescribed? Return to top
Bactrim, an antibacterial combination drug, is prescribed for the treatment of certain urinary tract infections, severe middle ear infections in children, long-lasting or frequently recurring bronchitis in adults that has increased in seriousness, inflammation of the intestine due to a severe bacterial infection, and travelers' diarrhea in adults. Bactrim is also prescribed for the treatment of Pneumocystis carinii pneumonia, and for prevention of this type of pneumonia in people with weakened immune systems.
Most important fact about this drug Return to top
Sulfamethoxazole, an ingredient in Bactrim, is one of a group of drugs called sulfonamides, which prevent the growth of bacteria in the body. Rare but sometimes fatal reactions have occurred with use of sulfonamides. These reactions include Stevens-Johnson syndrome (severe eruptions around the mouth, anus, or eyes), progressive disintegration of the outer layer of the skin, sudden and severe liver damage, a severe blood disorder (agranulocytosis), and a lack of red and white blood cells because of a bone marrow disorder.
Notify your doctor at the first sign of an adverse reaction such as skin rash, sore throat, fever, joint pain, cough, shortness of breath, abnormal skin paleness, reddish or purplish skin spots, or yellowing of the skin or whites of the eyes.
Frequent blood counts by a doctor are recommended for patients taking sulfonamide drugs.How should you take this medication? Return to top
It is important that you drink plenty of fluids while taking this medication in order to prevent sediment in the urine and the formation of stones.
Bactrim works best when there is a constant amount in the blood. Take Bactrim exactly as prescribed; try not to miss any doses. It is best to take doses at evenly spaced times day and night.
If you are taking Bactrim suspension, ask your pharmacist for a specially marked measuring spoon that delivers accurate doses.
--If you miss a dose...
Take the forgotten dose as soon as you remember. If it is almost time for your next dose, skip the one you missed and go back to your regular schedule. Do not take 2 doses at once.
Store tablets and suspension at room temperature and protect from light. Keep tablets in a dry place. Protect the suspension from freezing.
What side effects may occur? Return to top
Side effects cannot be anticipated. If any develop or change in intensity, inform your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking Bactrim.
More common side effects may include: Hives, lack or loss of appetite, nausea, skin rash, vomiting
Less common or rare side effects may include: Abdominal pain, allergic reactions, anemia, chills, convulsions, depression, diarrhea, eye irritation, fatigue, fever, hallucinations, headache, hepatitis, inability to fall or stay asleep, inability to urinate, increased urination, inflammation of heart muscle, inflammation of the mouth and/or tongue, itching, joint pain, kidney failure, lack of feeling or concern, lack of muscle coordination, loss of appetite, low blood sugar, meningitis (inflammation of the brain or spinal cord), muscle pain, nausea, nervousness, red, raised rash, redness and swelling of the tongue, ringing in the ears, scaling of dead skin due to inflammation, sensitivity to light, severe skin welts or swelling, skin eruptions, skin peeling, vertigo, weakness, yellowing of eyes and skin
Why should this drug not be prescribed? Return to top
If you are sensitive to or have ever had an allergic reaction to trimethoprim, sulfamethoxazole, or other sulfa drugs, you should not take this medication. Make sure that your doctor is aware of any drug reactions that you have experienced.
Unless you are directed to do so by your doctor, do not take this medication if you have been diagnosed as having megaloblastic anemia, which is a blood disorder due to a deficiency of folic acid.
This drug should not be given to infants less than 2 months of age.
Bactrim is not recommended for preventative or prolonged use in middle ear infections and should not be used in the treatment of streptococcal pharyngitis (strep throat) or certain other strep infections.
You should not take Bactrim if you are pregnant or nursing a baby.
Special warnings about this medication Return to top
Make sure your doctor knows if you have impaired kidney or liver function, have a folic acid deficiency, are a chronic alcoholic, are taking anticonvulsants, have been diagnosed as having malabsorption syndrome (abnormal intestinal absorption), are in a state of poor nutrition, or have severe allergies or bronchial asthma. Bactrim should be used cautiously under these conditions.
If you develop severe diarrhea, call your doctor. This drug can cause a serious intestinal inflammation.
If you have AIDS (acquired immunodeficiency syndrome) and are taking Bactrim to treat or prevent Pneumocystis carinii pneumonia, you will experience more side effects than will someone without AIDS.Possible food and drug interactions when taking this medication Return to top
If Bactrim is taken 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 Bactrim with the following:
Blood thinners such as Coumadin
Cyclosporine (Neoral, Sandimmune)
Oral diabetes medications such as Micronase and Glucotrol Pyrimethamine (Daraprim)
Seizure medications such as Dilantin
Tricyclic antidepressants such as Elavil, Norpramin, Sinequan, and Tofranil
Water pills (diuretics) such as HydroDIURIL
Special information if you are pregnant or breastfeeding Return to top
Bactrim should not be taken during pregnancy. If you are pregnant or plan to become pregnant, notify your doctor immediately. Bactrim does appear in breast milk and could affect a nursing infant. It should not be taken while breastfeeding.
Recommended dosage Return to top
Urinary Tract Infections and Intestinal Inflammation
The usual adult dosage in the treatment of urinary tract infection is 1 Bactrim DS (double strength tablet) or 2 Bactrim tablets, or 4 teaspoonfuls (20 milliliters) of Bactrim Pediatric Suspension every 12 hours for 10 to 14 days. The dosage for inflammation of the intestine is the same but is taken for 5 days.
Worsening of Chronic Bronchitis
The usual recommended dosage is 1 Bactrim DS (double strength tablet), 2 Bactrim tablets, or 4 teaspoonfuls (20 milliliters) of Bactrim Pediatric Suspension every 12 hours for 14 days.
Treatment of Pneumocystis Carinii Pneumonia
The recommended dosage is 15 to 20 milligrams of trimethoprim and 75 to 100 milligrams of sulfamethoxazole per 2.2 pounds of body weight per 24 hours divided into equal doses every 6 hours for 14 to 21 days.
Prevention of Pneumocystis Carinii Pneumonia
The recommended dosage is 1 Bactrim DS (double strength tablet) once daily.
The usual recommended dosage is 1 Bactrim DS (double strength tablet), 2 Bactrim tablets, or 4 teaspoonfuls (20 milliliters) of Bactrim Pediatric Suspension every 12 hours for 5 days.
Urinary Tract Infections or Middle Ear Infections
The recommended dosage for children 2 months of age or older, given every 12 hours for 10 days, is determined by weight. The following table is a guideline for this dosage: 22 pounds, 1 teaspoonful (5 milliliters) 44 pounds, 2 teaspoonfuls (10 milliliters) or 1 tablet 66 pounds, 3 teaspoonfuls (15 milliliters) or one-and-a-half tablets 88 pounds, 4 teaspoonfuls (20 milliliters) or 2 tablets or 1 DS tablet
The recommended dosage is identical to the dosage recommended for urinary tract and middle ear infections; however, it should be taken for 5 days.
Treatment of Pneumocystis Carinii Pneumonia
The recommended dosage, taken every 6 hours for 14 to 21 days, is determined by weight.
The following table is a guideline for this dosage:
18 pounds, 1 teaspoonful (5 milliliters)
35 pounds, 2 teaspoonfuls (10 milliliters) or 1 tablet
53 pounds, 3 teaspoonfuls (15 milliliters) or one-and-a-half tablets
70 pounds, 4 teaspoonfuls (20 milliliters) or 2 tablets or 1 DS tablet
Prevention of Pneumocystis Carinii Pneumonia
The recommended dosage, taken twice a day, on 3 consecutive days per week, is determined by body surface area. The total daily dose should not exceed 320 milligrams trimethoprim and 1600 milligrams sulfamethoxazole.
The safety of repeated use of Bactrim in children under 2 years of age has not been established.
There may be an increased risk of severe side effects when Bactrim is taken by older people, especially in those who have impaired kidney and/or liver function or who are taking other medication. Consult with your doctor before taking Bactrim.
Overdosage Return to top
If you suspect an overdose of Bactrim, seek emergency medical attention immediately.
Symptoms of an overdose of Bactrim include: Blood or sediment in the urine, colic, confusion, dizziness, drowsiness, fever, headache, lack or loss of appetite, mental depression, nausea, unconsciousness, vomiting, yellowed eyes and skin
Sulfonamides and Trimethoprim (Systemic)