Sulfamethoxazole and Trimethoprim
Tablet · Oral, Intravenous
Uses
To reduce the development of drug-resistant bacteria and maintain the effectiveness of sulfamethoxazole and trimethoprim oral suspension and other antibacterial drugs, sulfamethoxazole and trimethoprim oral suspension should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to empiric selection of therapy. Urinary Tract Infections For the treatment of urinary tract infections due to susceptible strains of the following organisms: Escherichia coli, Klebsiella species, Enterobacter species, Morganella morganii, Proteus mirabilis and Proteus vulgaris . It is recommended that initial episodes of uncomplicated urinary tract infections be treated with a single effective antibacterial agent rather than the combination. Acute Otitis Media For the treatment of acute otitis media in pediatric patients due to susceptible strains of Streptococcus pneumoniae or Haemophilus influenzae when in the judgment of the physician sulfamethoxazole and trimethoprim offers some advantage over the use of other antimicrobial agents. To date, there are limited data on the safety of repeated use of sulfamethoxazole and trimethoprim in pediatric patients under two years of age. Sulfamethoxazole and trimethoprim is not indicated for prophylactic or prolonged administration in otitis media at any age. Acute Exacerbations of Chronic Bronchitis in Adults For the treatment of acute exacerbations of chronic bronchitis due to susceptible strains of Streptococcus pneumoniae or Haemophilus influenzae when in the judgment of the physician sulfamethoxazole and trimethoprim offers some advantage over the use of a single antimicrobial agent. Shigellosis For the treatment of enteritis caused by susceptible strains of Shigella flexneri and Shigella sonnei when antibacterial therapy is indicated. Pneumocystis Carinii Pneumonia For the treatment of documented Pneumocystis carinii pneumonia and for prophylaxis against Pneumocystis carinii pneumonia in individuals who are immunosuppressed and considered to be at an increased risk of developing Pneumocystis carinii pneumonia. Travelers' Diarrhea in Adults For the treatment of travelers’ diarrhea due to susceptible strains of enterotoxigenic E. coli.
Dosage and administration
Not recommended for use in pediatric patients less than 2 months of age. Urinary Tract Infections and Shigellosis in Adults and Pediatric Patients, and Acute Otitis Media in Children Adults The usual adult dosage in the treatment of urinary tract infections is four teaspoonfuls (20 mL) Sulfamethoxazole and trimethoprim oral suspension every 12 hours for 10 to 14 days. An identical daily dosage is used for 5 days in the treatment of shigellosis. Children The recommended dose for children with urinary tract infections or acute otitis media is 40 mg/kg sulfamethoxazole and 8 mg/kg trimethoprim per 24 hours, given in two divided doses every 12 hours for 10 days. An identical daily dosage is used for 5 days in the treatment of shigellosis. The following table is a guideline for the attainment of this dosage: Children 2 months of age or older: Weight Dose - every 12 hours lb kg Teaspoonfuls 22 10 1 (5 mL) 44 20 2 (10 mL) 66 30 3 (15 mL) 88 40 4 (20 mL) For Patients with Impaired Renal Function: When renal function is impaired, a reduced dosage should be employed using the following table: Creatine Clearance (mL/min) Recommended Dosage Regimen Above 30 Use standard regimen 15 to 30 1/2 the usual regimen Below 15 Use not recommended Acute Exacerbations of Chronic Bronchitis in Adults The usual adult dosage in the treatment of acute exacerbations of chronic bronchitis is four teaspoonfuls (20 mL) sulfamethoxazole and trimethoprim oral suspension every 12 hours for 14 days. Pneumocystis Carinii Pneumonia Treatment Adults and Children: The recommended dosage for treatment of patients with documented Pneumocystis carinii pneumonia is 75 to 100 mg/kg sulfamethoxazole and 15 to 20 mg/kg trimethoprim per 24 hours given in equally divided doses every 6 hours for 14 to 21 days. 10 The following table is a guideline for the upper limit of this dosage: Weight Dose - every 6 hours lb kg Teaspoonfuls 18 8 1 (5 mL) 35 16 2 (10 mL) 53 24 3 (15 mL) 70 32 4 (20 mL) 88 40 5 (25 mL) 106 48 6 (30 mL) 141 64 8 (40 mL) 176 80 10 (50 mL) For the lower limit dose (75 mg/kg sulfamethoxazole and 15 mg/kg trimethoprim per 24 hours) administer 75% of the dose in the above table. Prophylaxis Adults The recommended dosage for prophylaxis in adults is four teaspoonfuls (20 mL) of the oral suspension daily. 11 Children For children, the recommended dose is 750 mg/m 2 /day sulfamethoxazole with 150 mg/m2/day trimethoprim given orally in equally divided doses twice a day, on 3 consecutive days per week. The total daily dose should not exceed 1600 mg sulfamethoxazole and 320 mg trimethoprim.12 The following table is a guideline for the attainment of this dosage in children: Body Surface Area Dose - every 12 hours (m 2 ) Teaspoonfuls 0.26 1/2 (2.5 mL) 0.53 1 (5 mL) 1.06 2 (10 mL) Travelers' Diarrhea in Adults For the treatment of travelers’ diarrhea, the usual adult dosage is four teaspoonfuls (20 mL) of sulfamethoxazole and trimethoprim oral suspension every 12 hours for 5 days.
Contraindications
Sulfamethoxazole and trimethoprim is contraindicated in patients with a known hypersensitivity to trimethoprim or sulfonamides, in patients with a history of drug-induced immune thrombocytopenia with use of trimethoprim and/or sulfonamides, and in patients with documented megaloblastic anemia due to folate deficiency. Sulfamethoxazole and trimethoprim is also contraindicated in pregnant patients and nursing mothers, because sulfonamides pass the placenta and are excreted in the milk and may cause kernicterus. Sulfamethoxazole and trimethoprim oral suspension is contraindicated in pediatric patients less than 2 months of age. Sulfamethoxazole and trimethoprim is also contraindicated in patients with marked hepatic damage or with severe renal insufficiency when renal function status cannot be monitored.
Warnings
Hypersensitivity and Other Serious or Fatal Reactions Fatalities and serious adverse reactions including severe cutaneous adverse reactions (SCARs) including Stevens-Johnson syndrome, toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms (DRESS), acute febrile neutrophilic dermatosis (AFND), acute generalized erythematous pustulosis (AGEP); fulminant hepatic necrosis; agranulocytosis, aplastic anemia and other blood dyscrasias; acute and delayed lung injury; anaphylaxis and circulatory shock have occurred with the administration of sulfamethoxazole and trimethoprim products, (see ADVERSE REACTIONS ). Cough, shortness of breath, and pulmonary infiltrates potentially representing hypersensitivity reactions of the respiratory tract have been reported in association with sulfamethoxazole and trimethoprim treatment. Other severe pulmonary adverse reactions occurring within days to weeks of sulfamethoxazole and trimethoprim initiation and resulting in prolonged respiratory failure requiring mechanical ventilation or extracorporeal membrane oxygenation (ECMO), lung transplantation or death have also been reported in patients and otherwise healthy individuals treated with sulfamethoxazole and trimethoprim products. Circulatory shock with fever, severe hypotension, and confusion requiring intravenous fluid resuscitation and vasopressors has occurred within minutes to hours of re-challenge with trimethoprim-sulfamethoxazole products in patients with history of recent (days to weeks) exposure to sulfamethoxazole and trimethoprim. Sulfamethoxazole and trimethoprim should be discontinued at the first appearance of skin rash or any sign of a serious adverse reaction. A skin rash may be followed by a more severe reaction, such as Stevens-Johnson syndrome, toxic epidermal necrolysis, DRESS, AFND, AGEP, hepatic necrosis, or serious blood disorders (see PRECAUTIONS and ADVERSE REACTIONS ). Clinical signs, such as rash, pharyngitis, fever, arthralgia, cough, chest pain, dyspnea, pallor, purpura or jaundice may be early indications of serious reactions. Thrombocytopenia Sulfamethoxazole/trimethoprim-induced thrombocytopenia may be an immune-mediated disorder. Severe cases of thrombocytopenia that are fatal or life threatening have been reported. Thrombocytopenia usually resolves within a week upon discontinuation of sulfamethoxazole/trimethoprim. The sulfonamides should not be used for the treatment of group A β-hemolytic streptococcal infections. In an established infection, they will not eradicate the streptococcus and, therefore, will not prevent sequelae such as rheumatic fever. Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including sulfamethoxazole and trimethoprim and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile. C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile , and surgical evaluation should be instituted as clinically indicated.
Precautions
General Prescribing sulfamethoxazole and trimethoprim in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria. Sulfamethoxazole and trimethoprim oral suspension should be given with caution to patients with impaired renal or hepatic function, to those with possible folate deficiency (e.g., the elderly, chronic alcoholics, patients receiving anticonvulsant therapy, patients with malabsorption syndrome, and patients in malnutrition states) and to those with severe allergies or bronchial asthma. In glucose-6- phosphate dehydrogenase deficient individuals, hemolysis may occur. This reaction is frequently dose-related (see CLINICAL PHARMACOLOGY and DOSAGE AND ADMINISTRATION ). Use in Elderly Cases of hypoglycemia in non-diabetic patients treated with sulfamethoxazole and trimethoprim are seen rarely, usually occurring after a few days of therapy. Patients with renal dysfunction, liver disease, malnutrition or those receiving high doses of sulfamethoxazole and trimethoprim are particularly at risk. Hematological changes indicative of folic acid deficiency may occur in elderly patients or in patients with preexisting folic acid deficiency or kidney failure. These effects are reversible by folinic acid therapy. Trimethoprim has been noted to impair phenylalanine metabolism, but this is of no significance in phenylketonuric patients on appropriate dietary restriction. As with all drugs containing sulfonamides, caution is advisable in patients with porphyria or thyroid dysfunction. Use in the Treatment of and Prophylaxis for Pneumocystis Carinii Pneumonia in Patients with Acquired Immunodeficiency Syndrome (AIDS) AIDS patients may not tolerate or respond to sulfamethoxazole and trimethoprim in the same manner as non-AIDS patients. The incidence of side effects, particularly rash, fever, leukopenia and elevated aminotransferase (transaminase) values, with sulfamethoxazole and trimethoprim therapy in AIDS patients who are being treated for Pneumocystis carinii pneumonia has been reported to be greatly increased compared with the incidence normally associated with the use of sulfamethoxazole and trimethoprim in non-AIDS patients. The incidence of hyperkalemia appears to be increased in AIDS patients receiving sulfamethoxazole and trimethoprim. Adverse effects are generally less severe in patients receiving sulfamethoxazole and trimethoprim for prophylaxis. A history of mild intolerance to sulfamethoxazole and trimethoprim oral suspension in AIDS patients does not appear to predict intolerance of subsequent secondary prophylaxis.6 However, if a patient develops skin rash or any sign of adverse reaction, therapy with sulfamethoxazole and trimethoprim should be reevaluated (see WARNINGS ). High dosage of trimethoprim, as used in patients with Pneumocystis carinii pneumonia, induces a progressive but reversible increase of serum potassium concentrations in a substantial number of patients. Even treatment with recommended doses may cause hyperkalemia when trimethoprim is administered to patients with underlying disorders of potassium metabolism, with renal insufficiency, or if drugs known to induce hyperkalemia are given concomitantly. Close monitoring of serum potassium is warranted in these patients. During treatment, adequate fluid intake and urinary output should be ensured to prevent crystalluria. Patients who are “slow acetylators” may be more prone to idiosyncratic reactions to sulfonamides. Information for Patients Patients should be counseled that antibacterial drugs including sulfamethoxazole and trimethoprim oral suspension should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When sulfamethoxazole and trimethoprim oral suspension is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by sulfamethoxazole and trimethoprim oral suspension or other antibacterial drugs in the future. Patients should be instructed to maintain an adequate fluid intake in order to prevent crystalluria and stone formation. Diarrhea is a common problem caused by antibiotics which usually ends when the antibiotic is discontinued. Sometimes after starting treatment with antibiotics, patients can develop watery and bloody stools (with and without stomach cramps and fever) even as late as two or more months after having taken the last dose of the antibiotic. If this occurs, patients should contact their physician as soon as possible. Laboratory tests Complete blood counts should be done frequently in patients receiving sulfamethoxazole and trimethoprim; if a significant reduction in the count of any formed blood element is noted, sulfamethoxazole and trimethoprim should be discontinued. Urinalyses with careful microscopic examination and renal function tests should be performed during therapy, particularly for those patients with impaired renal function. Drug Interactions In elderly patients concurrently receiving certain diuretics, primarily thiazides, an increased incidence of thrombocytopenia with purpura has been reported. It has been reported that sulfamethoxazole and trimethoprim may prolong the prothrombin time in patients who are receiving the anticoagulant warfarin. This interaction should be kept in mind when sulfamethoxazole and trimethoprim is given to patients already on anticoagulant therapy, and the coagulation time should be reassessed. Sulfamethoxazole and trimethoprim may inhibit the hepatic metabolism of phenytoin.
Side effects
The most common adverse reactions are gastrointestinal disturbances (nausea, vomiting, anorexia) and allergic skin reactions (such as rash and urticaria). Fatalities and serious adverse reactions, including severe cutaneous adverse reactions (SCARs), including Stevens-Johnson syndrome, toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms (DRESS), acute febrile neutrophilic dermatosis (AFND), acute generalized erythematous pustulosis (AGEP); fulminant hepatic necrosis; agranulocytosis, aplastic anemia and other blood dyscrasias; acute and delayed lung injury; anaphylaxis and circulatory shock have occurred with the administration of sulfamethoxazole and trimethoprim products, (see WARNINGS ). Hematologic Agranulocytosis, aplastic anemia, thrombocytopenia, leukopenia, neutropenia, hemolytic anemia, megaloblastic anemia, hypoprothrombinemia, methemoglobinemia, eosinophilia. Allergic Reactions Stevens-Johnson syndrome, toxic epidermal necrolysis, anaphylaxis, allergic myocarditis, erythema multiforme, exfoliative dermatitis, angioedema, drug fever, chills, Henoch-Schönlein purpura, serum sickness-like syndrome, generalized allergic reactions, generalized skin eruptions, photosensitivity, conjunctival and scleral injection, pruritus, urticaria and rash, periarteritis nodosa, systemic lupus erythematosus, drug reaction with eosinophilia and systemic symptoms (DRESS), acute generalized erythematous pustulosis (AGEP), and acute febrile neutrophilic dermatosis (AFND) (see WARNINGS ). Gastrointestinal Hepatitis (including cholestatic jaundice and hepatic necrosis) elevation of serum transaminase and bilirubin, pseudomembranous enterocolitis, pancreatitis, stomatitis, glossitis, nausea, emesis, abdominal pain, diarrhea, anorexia. Genitourinary Renal failure, interstitial nephritis, BUN and serum creatinine elevation, toxic nephrosis with oliguria and anuria, crystalluria and nephrotoxicity in association with cyclosporine. Metabolic and Nutritional Hyperkalemia (see PRECAUTIONS: Use in the Treatment of and Prophylaxis for Pneumocystis Carinii Pneumonia in Patients with Acquired Immunodeficiency Syndrome (AIDS) ). Neurologic Aseptic meningitis, convulsions, peripheral neuritis, ataxia, vertigo, tinnitus, headache. Psychiatric Hallucinations, depression, apathy, nervousness. Endocrine The sulfonamides bear certain chemical similarities to some goitrogens, diuretics (acetazolamide and the thiazides) and oral hypoglycemic agents. Cross-sensitivity may exist with these agents. Diuresis and hypoglycemia have occurred rarely in patients receiving sulfonamides. Musculoskeletal Arthralgia and myalgia. Isolated cases of rhabdomyolysis have been reported with sulfamethoxazole and trimethoprim, mainly in AIDS patients. Respiratory Cough, shortness of breath, pulmonary infiltrates, acute eosinophilic pneumonia, acute and delayed lung injury, interstitial lung disease, acute respiratory failure (see WARNINGS ). Cardiovascular Circulatory shock (see WARNINGS ), QT prolongation resulting in ventricular tachycardia and torsades de pointes . Miscellaneous Weakness, fatigue, insomnia. Postmarketing Experience The following adverse reactions have been identified during post-approval use of trimethoprim-sulfamethoxazole. Because these reactions were reported voluntarily from a population of uncertain size, it is not possible to reliably estimate their frequency or establish a causal relationship to drug exposure:
• Thrombotic thrombocytopenia purpura
• Idiopathic thrombocytopenic purpura
Drug interactions
Use in the Treatment of and Prophylaxis for Pneumocystis Carinii Pneumonia in Patients with Acquired Immunodeficiency Syndrome (AIDS) AIDS patients may not tolerate or respond to sulfamethoxazole and trimethoprim in the same manner as non-AIDS patients. The incidence of side effects, particularly rash, fever, leukopenia and elevated aminotransferase (transaminase) values, with sulfamethoxazole and trimethoprim therapy in AIDS patients who are being treated for Pneumocystis carinii pneumonia has been reported to be greatly increased compared with the incidence normally associated with the use of sulfamethoxazole and trimethoprim in non-AIDS patients. The incidence of hyperkalemia appears to be increased in AIDS patients receiving sulfamethoxazole and trimethoprim. Adverse effects are generally less severe in patients receiving sulfamethoxazole and trimethoprim for prophylaxis. A history of mild intolerance to sulfamethoxazole and trimethoprim oral suspension in AIDS patients does not appear to predict intolerance of subsequent secondary prophylaxis.6 However, if a patient develops skin rash or any sign of adverse reaction, therapy with sulfamethoxazole and trimethoprim should be reevaluated (see WARNINGS ). High dosage of trimethoprim, as used in patients with Pneumocystis carinii pneumonia, induces a progressive but reversible increase of serum potassium concentrations in a substantial number of patients. Even treatment with recommended doses may cause hyperkalemia when trimethoprim is administered to patients with underlying disorders of potassium metabolism, with renal insufficiency, or if drugs known to induce hyperkalemia are given concomitantly. Close monitoring of serum potassium is warranted in these patients. During treatment, adequate fluid intake and urinary output should be ensured to prevent crystalluria. Patients who are “slow acetylators” may be more prone to idiosyncratic reactions to sulfonamides.
Pregnancy
Laboratory tests Complete blood counts should be done frequently in patients receiving sulfamethoxazole and trimethoprim; if a significant reduction in the count of any formed blood element is noted, sulfamethoxazole and trimethoprim should be discontinued. Urinalyses with careful microscopic examination and renal function tests should be performed during therapy, particularly for those patients with impaired renal function. Pregnancy Teratogenic effects Pregnancy Category C. In rats, oral doses of 533 mg/kg or 200 mg/kg produced teratologic effects manifested mainly as cleft palates. The highest dose which did not cause cleft palates in rats was 512 mg/kg sulfamethoxazole or 192 mg/kg trimethoprim when administered separately. In two studies in rats, no teratology was observed when 512 mg/kg of sulfamethoxazole was used in combination with 128 mg/kg of trimethoprim. In one study, however, cleft palates were observed in one litter out of 9 when 355 mg/kg of sulfamethoxazole was used in combination with 88 mg/kg of trimethoprim. In some rabbit studies, an overall increase in fetal loss (dead and resorbed and malformed conceptuses) was associated with doses of trimethoprim 6 times the human therapeutic dose. While there are no large, well-controlled studies on the use of sulfamethoxazole and trimethoprim in pregnant women, Brumfitt and Pursell, 9 in a retrospective study, reported the outcome of 186 pregnancies during which the mother received either placebo or sulfamethoxazole and trimethoprim. The incidence of congenital abnormalities was 4.5% (3 of 66) in those who received placebo and 3.3% (4 of 120) in those receiving sulfamethoxazole and trimethoprim. There were no abnormalities in the 10 children whose mothers received the drug during the first trimester. In a separate survey, Brumfitt and Pursell also found no congenital abnormalities in 35 children whose mothers had received oral sulfamethoxazole and trimethoprim at the time of conception or shortly thereafter. Because sulfamethoxazole and trimethoprim may interfere with folic acid metabolism, sulfamethoxazole and trimethoprim should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Pediatric use
Drug/Laboratory Test Interactions Sulfamethoxazole and trimethoprim, specifically the trimethoprim component, can interfere with a serum methotrexate assay as determined by the competitive binding protein technique (CBPA) when a bacterial dihydrofolate reductase is used as the binding protein. No interference occurs, however, if methotrexate is measured by a radioimmunoassay (RIA). The presence of sulfamethoxazole and trimethoprim may also interfere with the Jaffé alkaline picrate reaction assay for creatinine, resulting in overestimations of about 10% in the range of normal values. Pediatric use Sulfamethoxazole and trimethoprim is not recommended for infants younger than 2 months of age (see INDICATIONS AND USAGE and CONTRAINDICATIONS section).
Geriatric use
Geriatric use Clinical studies of sulfamethoxazole and trimethoprim did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. There may be an increased risk of severe adverse reactions in elderly patients, particularly when complicating conditions exist, e.g., impaired kidney and/or liver function, possible folate deficiency, or concomitant use of other drugs. Severe skin reactions, generalized bone marrow suppression (see WARNINGS and ADVERSE REACTIONS sections), a specific decrease in platelets (with or without purpura), and hyperkalemia are the most frequently reported severe adverse reactions in elderly patients. In those concurrently receiving certain diuretics, primarily thiazides, an increased incidence of thrombocytopenia with purpura has been reported. Increased digoxin blood levels can occur with concomitant sulfamethoxazole and trimethoprim therapy, especially in elderly patients. Serum digoxin levels should be monitored. Hematological changes indicative of folic acid deficiency may occur in elderly patients. These effects are reversible by folinic acid therapy. Appropriate dosage adjustments should be made for patients with impaired kidney function and duration of use should be as short as possible to minimize risks of undesired reactions (see DOSAGE AND ADMINISTRATION sections). The trimethoprim component of sulfamethoxazole and trimethoprim may cause hyperkalemia when administered to patients with underlying disorders of potassium metabolism, with renal insufficiency or when given concomitantly with drugs known to induce hyperkalemia, such as angiotensin converting enzyme inhibitors. Close monitoring of serum potassium is warranted in these patients. Discontinuation of sulfamethoxazole and trimethoprim treatment is recommended to help lower potassium serum levels. Pharmacokinetics parameters for sulfamethoxazole were similar for geriatric subjects and younger adult subjects. The mean maximum serum trimethoprim concentration was higher and mean renal clearance of trimethoprim was lower in geriatric subjects compared with younger subjects (see CLINICAL PHARMACOLOGY: Geriatric Pharmacokinetics ).
Overdosage
Acute The amount of a single dose of sulfamethoxazole and trimethoprim that is either associated with symptoms of overdosage or is likely to be life-threatening has not been reported.Signs and symptoms of overdosage reported with sulfonamides include anorexia, colic, nausea, vomiting, dizziness, headache, drowsiness and unconsciousness. Pyrexia, hematuria and crystalluria may be noted. Blood dyscrasias and jaundice are potential late manifestations of overdosage. Signs of acute overdosage with trimethoprim include nausea, vomiting, dizziness, headache, mental depression, confusion and bone marrow depression. General principles of treatment include the institution of gastric lavage or emesis, forcing oral fluids, and the administration of intravenous fluids if urine output is low and renal function is normal. Acidification of the urine will increase renal elimination of trimethoprim. The patient should be monitored with blood counts and appropriate blood chemistries, including electrolytes. If a significant blood dyscrasia or jaundice occurs, specific therapy should be instituted for these complications. Peritoneal dialysis is not effective and hemodialysis is only moderately effective in eliminating sulfamethoxazole and trimethoprim. Chronic Use of sulfamethoxazole and trimethoprim at high doses and/or for extended periods of time may cause bone marrow depression manifested as thrombocytopenia, leukopenia and/or megaloblastic anemia. If signs of bone marrow depression occur, the patient should be given leucovorin 5 to 15 mg daily until normal hematopoiesis is restored.
Description
Sulfamethoxazole and trimethoprim is a synthetic antibacterial combination product containing 200 mg sulfamethoxazole and 40 mg trimethoprim per 5 mL for oral administration. Sulfamethoxazole is N 1 -(5-methyl-3-isoxazolyl) sulfanilamide; the molecular formula is C 10 H 11 N 3 O 3 S. It is an almost white, odorless, tasteless compound with a molecular weight of 253.28 and the following structural formula is: Trimethoprim is 2,4-diamino-5-(3,4,5- trimethoxybenzyl) pyrimidine; the molecular formula is C 14 H 18 N 4 O 3 . It is a white to light yellow, odorless, bitter compound with a molecular weight of 290.3 and it has the following structural formula is: Sulfamethoxazole - structure Trimethoprin - structure INACTIVE INGREDIENTS: alcohol (less than 0.5%), carboxymethylcellulose sodium, citric acid, FD&C Red #40, FD&C Yellow #6, cherry flavor, methylparaben, microcrystalline cellulose and carboxymethylcellulose sodium, polysorbate 80, propylene glycol, propylparaben, purified water, saccharin sodium, simethicone emulsion, sucrose.
How supplied
Sulfamethoxazole and Trimethoprim Oral Suspension, USP, containing 200 mg sulfamethoxazole and 40 mg trimethoprim per teaspoonful (5 mL), is a cherry flavored suspension available in: NDC 0121-0853-20: 20 mL unit dose cup, in a tray of ten cups. Store at 20°-25°C (68°-77°F) [see USP Controlled Room Temperature]. Protect from light. SHAKE WELL BEFORE USING. Dispense in a tight, light-resistant container as defined in the USP, with a child-resistant closure (as required). To report SUSPECTED ADVERSE REACTIONS, contact Pharmaceutical Associates, Inc. at 1-800-845-8210 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. Rx only
Label text from the FDA structured product label by PAI Holdings, LLC dba PAI Pharma (revised Aug 1, 2024). Long sections are shortened; the complete label is on DailyMed.
Active ingredients
- Sulfamethoxazole in 94 products
- Trimethoprim in 94 products
Sulfamethoxazole and Trimethoprim NDC products (94)
| NDC | Strength & form | Labeler | Type |
|---|---|---|---|
| 50090-2198 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-6901 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-5682 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-5680 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-5679 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-4850 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-4848 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-4847 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-2479 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-2201 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-2200 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-2199 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-0525 | Sulfamethoxazole 200 mg/5mL; Trimethoprim 40 mg/5mL Suspension | A-S Medication Solutions | ANDA |
| 50090-6902 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-6904 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-7008 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-7393 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 50090-7399 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | A-S Medication Solutions | ANDA |
| 80425-0001 | Trimethoprim 160 mg/1; Sulfamethoxazole 800 mg/1 Tablet | Advanced Rx Pharmacy of Tennessee, LLC | ANDA |
| 80425-0002 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Advanced Rx Pharmacy of Tennessee, LLC | ANDA |
| 80425-0003 | Trimethoprim 160 mg/1; Sulfamethoxazole 800 mg/1 Tablet | Advanced Rx Pharmacy of Tennessee, LLC | ANDA |
| 60687-442 | Sulfamethoxazole 200 mg/5mL; Trimethoprim 40 mg/5mL Suspension | American Health Packaging | ANDA |
| 60687-614 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | American Health Packaging | ANDA |
| 65162-272 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Amneal Pharmaceuticals LLC | ANDA |
| 65162-271 | Sulfamethoxazole 400 mg/1; Trimethoprim 80 mg/1 Tablet | Amneal Pharmaceuticals LLC | ANDA |
| 53746-271 | Sulfamethoxazole 400 mg/1; Trimethoprim 80 mg/1 Tablet | Amneal Pharmaceuticals of New York LLC | ANDA |
| 53746-272 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Amneal Pharmaceuticals of New York LLC | ANDA |
| 70954-258 | Sulfamethoxazole 200 mg/5mL; Trimethoprim 40 mg/5mL Suspension | ANI Pharmaceuticals, Inc. | ANDA |
| 76420-064 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Asclemed USA, Inc. | ANDA |
| 17856-0496 | Sulfamethoxazole 200 mg/5mL; Trimethoprim 40 mg/5mL Suspension | ATLANTIC BIOLOGICALS CORP. | ANDA |
| 65862-419 | Sulfamethoxazole 400 mg/1; Trimethoprim 80 mg/1 Tablet | Aurobindo Pharma Limited | ANDA |
| 65862-420 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Aurobindo Pharma Limited | ANDA |
| 65862-496 | Sulfamethoxazole 200 mg/5mL; Trimethoprim 40 mg/5mL Suspension | Aurobindo Pharma Limited | ANDA |
| 42291-759 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | AvKARE | ANDA |
| 42291-758 | Sulfamethoxazole 400 mg/1; Trimethoprim 80 mg/1 Tablet | AvKARE | ANDA |
| 50268-728 | Sulfamethoxazole 400 mg/1; Trimethoprim 80 mg/1 Tablet | AvPAK | ANDA |
| 63629-1765 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Bryant Ranch Prepack | ANDA |
| 71335-0762 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Bryant Ranch Prepack | ANDA |
| 55154-7895 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Cardinal Health 107, LLC | ANDA |
| 55154-2580 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Cardinal Health 107, LLC | ANDA |
| 68999-873 | Sulfamethoxazole 800 mg/20mL; Trimethoprim 160 mg/20mL Suspension | Chartwell Governmental & Specialty RX, LLC. | ANDA |
| 62135-749 | Sulfamethoxazole 200 mg/5mL; Trimethoprim 40 mg/5mL Suspension | Chartwell RX, LLC | ANDA |
| 62135-873 | Sulfamethoxazole 800 mg/20mL; Trimethoprim 160 mg/20mL Suspension | Chartwell RX, LLC | ANDA |
| 62135-897 | Sulfamethoxazole 400 mg/1; Trimethoprim 80 mg/1 Tablet | Chartwell RX, LLC | ANDA |
| 62135-898 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Chartwell RX, LLC | ANDA |
| 67046-0295 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Coupler LLC | ANDA |
| 69043-010 | Sulfamethoxazole 400 mg/1; Trimethoprim 80 mg/1 Tablet | Cronus Pharma LLC | ANDA |
| 69043-011 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Cronus Pharma LLC | ANDA |
| 70934-544 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Denton Pharma, Inc. DBA Northwind Pharmaceuticals | ANDA |
| 60429-259 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Golden State Medical Supply, Inc. | ANDA |
| 81033-012 | Sulfamethoxazole 200 mg/5mL; Trimethoprim 40 mg/5mL Suspension | Kesin Pharma | ANDA |
| 0904-2725 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Major Pharmaceuticals | ANDA |
| 0615-8121 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | NCS HealthCare of KY, LLC dba Vangard Labs | ANDA |
| 51655-307 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Northwind Health Company, LLC | ANDA |
| 51655-188 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Northwind Health Company, LLC | ANDA |
| 82868-092 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Northwind Health Company, LLC | ANDA |
| 66267-196 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | NuCare Pharmaceuticals, Inc. | ANDA |
| 66267-816 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | NuCare Pharmaceuticals, Inc. | ANDA |
| 68071-3579 | Sulfamethoxazole 400 mg/1; Trimethoprim 80 mg/1 Tablet | NuCare Pharmaceuticals,Inc. | ANDA |
| 68071-4710 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | NuCare Pharmaceuticals,Inc. | ANDA |
| 68071-4948 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | NuCare Pharmaceuticals,Inc. | ANDA |
| 72789-018 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | PD-Rx Pharmaceuticals, Inc. | ANDA |
| 72789-064 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | PD-Rx Pharmaceuticals, Inc. | ANDA |
| 82982-044 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Pharmasource Meds, LLC | ANDA |
| 66993-727 | Sulfamethoxazole 200 mg/5mL; Trimethoprim 40 mg/5mL Suspension | Prasco Laboratories | ANDA |
| 68788-7622 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Preferred Pharmaceuticals Inc. | ANDA |
| 68788-8607 | Sulfamethoxazole 200 mg/5mL; Trimethoprim 40 mg/5mL Suspension | Preferred Pharmaceuticals Inc. | ANDA |
| 63187-008 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Proficient Rx LP | ANDA |
| 63187-782 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Proficient Rx LP | ANDA |
| 71205-810 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Proficient Rx LP | ANDA |
| 63187-695 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Proficient Rx LP | ANDA |
| 42708-053 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | QPharma, Inc. | ANDA |
| 55700-611 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Quality Care Products LLC | ANDA |
| 70518-0863 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | REMEDYREPACK INC. | ANDA |
| 70518-2604 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | REMEDYREPACK INC. | ANDA |
| 70518-3432 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | REMEDYREPACK INC. | ANDA |
| 70518-3454 | Sulfamethoxazole 400 mg/1; Trimethoprim 80 mg/1 Tablet | REMEDYREPACK INC. | ANDA |
| 57237-232 | Sulfamethoxazole 400 mg/1; Trimethoprim 80 mg/1 Tablet | Rising Pharma Holdings, Inc. | ANDA |
| 57237-233 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Rising Pharma Holdings, Inc. | ANDA |
| 70069-363 | Sulfamethoxazole 80 mg/mL; Trimethoprim 16 mg/mL Injection, Solution, Concentrate | Somerset Therapeutics, LLC | ANDA |
| 70069-362 | Sulfamethoxazole 80 mg/mL; Trimethoprim 16 mg/mL Injection, Solution, Concentrate | Somerset Therapeutics, LLC | ANDA |
| 70069-361 | Sulfamethoxazole 80 mg/mL; Trimethoprim 16 mg/mL Injection, Solution, Concentrate | Somerset Therapeutics, LLC | ANDA |
| 85766-015 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Sportpharm LLC | ANDA |
| 60760-541 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | St. Mary's Medical Park Pharmacy | ANDA |
| 53489-145 | Sulfamethoxazole 400 mg/1; Trimethoprim 80 mg/1 Tablet | Sun Pharmaceutical Industries, Inc. | ANDA |
| 53489-146 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Sun Pharmaceutical Industries, Inc. | ANDA |
| 0703-9526 | Sulfamethoxazole 80 mg/mL; Trimethoprim 16 mg/mL Injection, Solution, Concentrate | Teva Parenteral Medicines, Inc. | ANDA |
| 0703-9514 | Sulfamethoxazole 80 mg/mL; Trimethoprim 16 mg/mL Injection, Solution, Concentrate | Teva Parenteral Medicines, Inc. | ANDA |
| 0703-9503 | Sulfamethoxazole 80 mg/mL; Trimethoprim 16 mg/mL Injection, Solution, Concentrate | Teva Parenteral Medicines, Inc. | ANDA |
| 87441-078 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Unit Dose Solutions, Inc. | ANDA |
| 83939-0023 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | VERITYRX, LLC | ANDA |
| 61971-115 | Sulfamethoxazole 400 mg/1; Trimethoprim 80 mg/1 Tablet | Vista Pharmaceuticals, Inc. | ANDA |
| 61971-120 | Sulfamethoxazole 800 mg/1; Trimethoprim 160 mg/1 Tablet | Vista Pharmaceuticals, Inc. | ANDA |
| 0121-0853 | Sulfamethoxazole 200 mg/5mL; Trimethoprim 40 mg/5mL Suspension | PAI Holdings, LLC dba PAI Pharma | NDA |
Sulfamethoxazole and Trimethoprim recalls
- D-0654-2025 Sep 24, 2025 · Class II · Ongoing
Presence of a Foreign Substance: A specific lot of auxiliary polyester coil, used in product packaging by manufacturer (Amneal Pharmaceuticals LLC) was detected with presence of a micro-organism. No micro-organism was… - D-0624-2025 Sep 17, 2025 · Class II · Ongoing
Presence of a Foreign Substance: A specific lot of auxiliary polyester coil, used in product packaging by manufacturer (Amneal Pharmaceuticals LLC) was detected with presence of a micro-organism. No micro-organism was… - D-0625-2025 Sep 17, 2025 · Class II · Ongoing
Presence of a Foreign Substance: A specific lot of auxiliary polyester coil, used in product packaging by manufacturer (Amneal Pharmaceuticals LLC) was detected with presence of a micro-organism. No micro-organism was… - D-0615-2025 Sep 10, 2025 · Class II · Ongoing
Presence of a foreign substance.A specific lot of auxiliary polyester coil, used in product packaging was detected with presence of a micro-organism. No micro-organism was detected on any tablets. - D-0488-2025 Jun 18, 2025 · Class I · Ongoing
Microbial contamination of non-sterile products: tablets may exhibit black spots due to microbial contamination. - D-1059-2022 Jun 15, 2022 · Class II · Terminated
cGMP deviations: Temperature abuse - D-0719-2021 Aug 18, 2021 · Class II · Terminated
Presence of Foreign Substance- Potential of metal contamination. - D-1535-2020 Sep 2, 2020 · Class II · Terminated
Presence of Foreign Substance: product complaints were received by the firm for the presence of metal wire in the tablet(s). - D-0802-2018 May 23, 2018 · Class II · Terminated
Presence of Foreign Substance:Sun Pharma is recalling one (1) lot of Sulfamethoxazole and Trimethoprim Tablets USP, 800 mg/160 mg (500 ct.) because a foreign matter identified as polyethylene was detected in two (2)… - D-1450-2014 Jul 30, 2014 · Class II · Terminated
Labeling: Label Mix up; product labeled to contain Sulfamethoxazole and Trimethoprim Tablets, 400 mg/80 mg instead of Sulfamethoxazole and Trimethoprim Tablets, 800 mg/160 mg
Frequently asked questions
What is Sulfamethoxazole and Trimethoprim used for?
To reduce the development of drug-resistant bacteria and maintain the effectiveness of sulfamethoxazole and trimethoprim oral suspension and other antibacterial drugs, sulfamethoxazole and trimethoprim oral suspension should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are…
What are the side effects of Sulfamethoxazole and Trimethoprim?
The most common adverse reactions are gastrointestinal disturbances (nausea, vomiting, anorexia) and allergic skin reactions (such as rash and urticaria). Fatalities and serious adverse reactions, including severe cutaneous adverse reactions (SCARs), including Stevens-Johnson syndrome, toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms (DRESS), acute febrile… See the full label for the complete list.
Who makes Sulfamethoxazole and Trimethoprim?
Sulfamethoxazole and Trimethoprim is listed by 43 labelers in the FDA NDC directory, including A-S Medication Solutions, Advanced Rx Pharmacy of Tennessee, LLC, American Health Packaging, Amneal Pharmaceuticals LLC.
Has Sulfamethoxazole and Trimethoprim been recalled?
The FDA enforcement database lists 10 recalls for Sulfamethoxazole and Trimethoprim, most recently D-0654-2025 (class ii): Presence of a Foreign Substance: A specific lot of auxiliary polyester coil, used in product packaging by manufacturer (Amneal Pharmaceuticals LLC) was…