Sulfamethoxazole (28 brand names, 3 dosage forms, 2 routes)
Available dosage forms: TABLET, SUSPENSION, INJECTABLE.
Routes of administration: ORAL, INJECTION.
Brand Names
- AZO GANTANOL
- BACTRIM
- BACTRIM DS
- BACTRIM PEDIATRIC
- COTRIM
- COTRIM D.S.
- GANTANOL
- GANTANOL-DS
- SEPTRA
- SEPTRA DS
- SEPTRA GRAPE
- SULFAMETHOPRIM
- SULFAMETHOPRIM-DS
- SULFAMETHOXAZOLE
- SULFAMETHOXAZOLE AND TRIMETHOPRIM
- SULFAMETHOXAZOLE AND TRIMETHOPRIM AND PHENAZOPYRIDINE HYDROCHLORIDE
- SULFAMETHOXAZOLE AND TRIMETHOPRIM DOUBLE STRENGTH
- SULFAMETHOXAZOLE AND TRIMETHOPRIM SINGLE STRENGTH
- SULFATRIM
- SULFATRIM PEDIATRIC …and 8 more
Indications and Usage
To reduce the development of drug-resistant bacteria and maintain the effectiveness of sulfamethoxazole and trimethoprim tablets and other antibacterial drugs, sulfamethoxazole and trimethoprim tablets 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.
Dosage and Administration
Sulfamethoxazole and trimethoprim tablets are contraindicated in pediatric patients less than 2 months of age.
Contraindications
Sulfamethoxazole and trimethoprim tablets are contraindicated in the following situations: known hypersensitivity to trimethoprim or sulfonamides history of drug-induced immune thrombocytopenia with use of trimethoprim and/or sulfonamides documented megaloblastic anemia due to folate deficiency pediatric patients less than 2 months of age marked hepatic damage severe renal insufficiency when renal function status cannot be monitored concomitant administration with dofetilide (see PRECAUTIONS ).
Adverse Reactions
The following adverse reactions associated with the use of sulfamethoxazole and trimethoprim were identified in clinical trials, postmarketing or published reports. Because some of these reactions were reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. 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, including sulfamethoxazole and trimethoprim (see WARNINGS ). Hematologic: Agranulocytosis, aplastic anemia, thrombocytopenia, leukopenia, neutropenia, hemolytic anemia, megaloblastic anemia, hypoprothrombinemia, methemoglobinemia, eosinophilia, thrombotic thrombocytopenic purpura, idiopathic thrombocytopenic purpura. Allergic Reactions: Stevens-Johnson syndrome, toxic epidermal necrolysis, anaphylaxis, allergic myocarditis, erythema multiforme, exfoliative dermatitis, angioedema, drug fever, chills, Henoch-Schoenlein purpura, serum sickness-like syndrome, generalized allergic reactions, generalized skin eruptions, photosensitivity, conjunctival and scleral injection, pruritus, urticaria, rash, periarteritis nodosa, systemic lupus erythematosus, drug reaction with eosinophilia and systemic symptoms (DRESS), acute generalized erythematous pustulosis (AGEP), and acute febrile neutrophilic dermatosis (
Drug Interactions
Potential for Sulfamethoxazole and Trimethoprim to Affect Other Drugs Trimethoprim is an inhibitor of CYP2C8 as well as OCT2 transporter. Sulfamethoxazole is an inhibitor of CYP2C9. Avoid coadministration of sulfamethoxazole and trimethoprim with drugs that are substrates of CYP2C8 and 2C9 or OCT2. Table 1: Drug Interactions with Sulfamethoxazole and Trimethoprim Drug(s) Recommendation Comments Diuretics Avoid concurrent use In elderly patients concurrently receiving certain diuretics, primarily thiazides, an increased incidence of thrombocytopenia with purpura has been reported. Warfarin Monitor prothrombin time and INR It has been reported that sulfamethoxazole and trimethoprim may prolong the prothrombin time in patients who are receiving the anticoagulant warfarin (a CYP2C9 substrate). 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. Phenytoin Monitor serum phenytoin levels Sulfamethoxazole and trimethoprim may inhibit the hepatic metabolism of phenytoin (a CYP2C9 substrate). Sulfamethoxazole and trimethoprim, given at a common clinical dosage, increased the phenytoin half-life by 39% and decreased the phenytoin metabolic clearance rate by 27%. When administering these drugs concurrently, one should be alert for possible excessive phenytoin effect. Methotrexate Avoid concurrent use Sulfonamides can also displace methotrexate from plasma protein binding sites and can compete with the renal transport of methotrexate, thus increasing free methotrexate concentrations. Cyclosporine Avoid concurrent use There have been reports of marked but reversible nephrotoxicity with coadministration of sulfamethoxazole and trimethoprim and cyclosporine in renal transplant recipients. Digoxin Monitor serum digoxin levels Increased digoxin blood levels can occur with concomitant sulfamethoxazole and trimethoprim therapy, especially in elderly patients.