Trimethoprim/sulfamethoxazole

{{Short description|Combination of two antibiotic drugs}} {{Use dmy dates|date=January 2025}} {{cs1 config |name-list-style=vanc |display-authors=6}} {{Infobox drug | verifiedrevid = 388518461 | type = combo | image = Trimethoprim and sulfamethoxazole.svg | image_class = skin-invert-image | width = 200 | alt = | caption = Trimethoprim (top) and sulfamethoxazole (bottom) | BAN = Co-trimoxazole

| component1 = Sulfamethoxazole | class1 = Sulfonamide antibiotic | component2 = Trimethoprim | class2 = Dihydrofolate reductase inhibitor

| tradename = Bactrim, Cotrim, Septra, others | Drugs.com = {{drugs.com|monograph|co-trimoxazole}} | MedlinePlus = | DailyMedID = Sulfamethoxazole trimethoprim | pregnancy_AU = C | pregnancy_AU_comment = <ref name="Drugs.com pregnancy">{{Cite web |date=8 March 2019 |title=Sulfamethoxazole / trimethoprim Use During Pregnancy |url=https://www.drugs.com/pregnancy/sulfamethoxazole-trimethoprim.html |url-status=live |archive-url=https://web.archive.org/web/20150906073951/http://www.drugs.com/pregnancy/sulfamethoxazole-trimethoprim.html |archive-date=6 September 2015 |access-date=15 April 2020 |website=Drugs.com}}</ref> | pregnancy_category = | routes_of_administration = Oral, Intravenous infusion<ref name="AHFS2015" /> | ATC_prefix = J01 | ATC_suffix = EE01 | ATC_supplemental = {{ATC|J04|AM08}}

| legal_AU = S4 | legal_AU_comment = <ref name="TGA">{{Cite web |title=Bactrim DS tablet blister pack |url=https://tga-search.clients.funnelback.com/s/search.html?collection=tga-artg&profile=record&meta_i=162563 |url-status=live |archive-url=https://web.archive.org/web/20211229045805/https://tga-search.clients.funnelback.com/s/search.html?collection=tga-artg&profile=record&meta_i=162563 |archive-date=29 December 2021 |access-date=28 December 2021 |website=Therapeutic Goods Administration (TGA)}}</ref><ref>{{Cite web |title=TGA eBS – Product and Consumer Medicine Information Licence |url=http://www.ebs.tga.gov.au/ebs/picmi/picmirepository.nsf/pdf?OpenAgent&id=CP-2021-PI-01633-1 |url-status=live |archive-url=https://web.archive.org/web/20211229045813/https://www.ebs.tga.gov.au/ebs/picmi/picmirepository.nsf/pdf?OpenAgent&id=CP-2021-PI-01633-1 |archive-date=29 December 2021 |access-date=29 December 2021}}</ref> | legal_BR =  | legal_BR_comment = | legal_CA = Rx-only | legal_CA_comment = | legal_DE =  | legal_DE_comment = | legal_NZ =  | legal_NZ_comment = | legal_UK = POM | legal_UK_comment = <ref name="Co-Trimoxazole SmPC">{{Cite web |date=1 August 2021 |title=Co-Trimoxazole 80 mg/400 mg Tablets – Summary of Product Characteristics (SmPC) |url=https://www.medicines.org.uk/emc/product/6999/smpc |url-status=live |archive-url=https://web.archive.org/web/20211229045804/https://www.medicines.org.uk/emc/product/6999/smpc |archive-date=29 December 2021 |access-date=28 December 2021 |website=(emc)}}</ref> | legal_US = Rx-only | legal_US_comment = <ref name="Bactrim FDA label">{{Cite web |title=Bactrim DS- sulfamethoxazole and trimethoprim tablet Bactrim- sulfamethoxazole and trimethoprim tablet |url=https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=f59d0c04-9c66-4d53-a0e1-cb55570deb62 |url-status=live |archive-url=https://web.archive.org/web/20211229045803/https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=f59d0c04-9c66-4d53-a0e1-cb55570deb62 |archive-date=29 December 2021 |access-date=28 December 2021 |website=DailyMed}}</ref> | legal_EU = | legal_EU_comment = | legal_UN =  | legal_UN_comment = | legal_status =

| CAS_number_Ref = | CAS_number = 8064-90-2 | CAS_supplemental = | PubChem = 358641 | IUPHAR_ligand = | DrugBank = | ChemSpiderID_Ref = | ChemSpiderID = 318412 | UNII_Ref = | UNII = | KEGG_Ref = | KEGG = D00285 | ChEBI_Ref = | ChEBI = 3770 | ChEMBL_Ref = | ChEMBL = 58061 | NIAID_ChemDB = | PDB_ligand = | synonyms = TMP/SMX  }}

'''Trimethoprim/sulfamethoxazole''', sold under the trade names '''Bactrim''', '''Cotrim''' (a short form of the British Approved Name, '''Co-trimoxazole''') and '''Septra''', among others, is a fixed-dose combination antibiotic medication used to treat a variety of bacterial infections.<ref name="AHFS2015">{{Cite web |title=Co-trimoxazole |url=https://www.drugs.com/monograph/co-trimoxazole.html |url-status=live |archive-url=https://web.archive.org/web/20150906003435/http://www.drugs.com/monograph/co-trimoxazole.html |archive-date=6 September 2015 |access-date=1 August 2015 |publisher=The American Society of Health-System Pharmacists}}</ref> It consists of one part trimethoprim to five parts sulfamethoxazole.<ref name="Ric2015" /> It is used to treat urinary tract infections, methicillin-resistant Staphylococcus aureus (MRSA) skin infections, travelers' diarrhea, respiratory tract infections, and cholera, among others.<ref name="AHFS2015" /><ref name="Ric2015" /> It is used both to treat and prevent ''pneumocystis'' pneumonia and toxoplasmosis in people with HIV/AIDS and other causes of immunosuppression.<ref name="AHFS2015" /> It can be given orally (swallowed by mouth) or intravenous infusion (slowly injected into a vein with an IV).<ref name="AHFS2015" />

Trimethoprim/sulfamethoxazole is on the World Health Organization's List of Essential Medicines.<ref name="WHO23rd">{{Cite book |title=The selection and use of essential medicines 2023: web annex A: World Health Organization model list of essential medicines: 23rd list (2023) |publisher=World Health Organization |year=2023 |location=Geneva |hdl=10665/371090 |id=WHO/MHP/HPS/EML/2023.02 |hdl-access=free}}</ref> It is available as a generic medication.<ref name="Ric2015">{{Cite book |title=Tarascon Pocket Pharmacopoeia 2015 Deluxe Lab-Coat Edition |vauthors=Hamilton R |date=2015 |publisher=Jones & Bartlett Learning |isbn=978-1-284-05756-0 |page=105}}</ref><ref name="Brown2019" /> In 2023, it was the 128th most commonly prescribed medication in the United States, with more than 4{{nbsp}}million prescriptions.<ref name="Top 300">{{cite web | title=Top 300 of 2023 | url=https://clincalc.com/DrugStats/Top300Drugs.aspx | website=ClinCalc | access-date=12 August 2025 | archive-date=12 August 2025 | archive-url=https://web.archive.org/web/20250812130026/https://clincalc.com/DrugStats/Top300Drugs.aspx | url-status=live }}</ref><ref>{{Cite web |title=Sulfamethoxazole; Trimethoprim Drug Usage Statistics, United States, 2013–2023 |url=https://clincalc.com/DrugStats/Drugs/SulfamethoxazoleTrimethoprim |access-date=18 August 2025 |website=ClinCalc}}</ref>

== Medical uses == Trimethoprim/sulfamethoxazole generally kills bacteria, by blocking the microorganisms' ability to make and to use folate.<ref name="AHFS2015" />

=== ''Pneumocystis jirovecii'' pneumonia === Trimethoprim/sulfamethoxazole (TMP/SMX) is the medicine most commonly used to prevent ''Pneumocystis jirovecii'' pneumonia (PCP)<ref name="cdc.gov">{{Cite web |date=13 October 2021 |title=Pneumocystis pneumonia |url=https://www.cdc.gov/fungal/diseases/pneumocystis-pneumonia/index.html |url-status=live |archive-url=https://web.archive.org/web/20210726083526/https://www.cdc.gov/fungal/diseases/pneumocystis-pneumonia/index.html |archive-date=26 July 2021 |access-date=30 December 2021 |website=U.S. Centers for Disease Control and Prevention (CDC)}}</ref> People who get ''Pneumocystis'' pneumonia have a medical condition that weakens their immune system, like HIV/AIDS, or take medicines (such as corticosteroid, monoclonal antibody and immunosuppressants) that reduce the body's ability to fight bacterial and viral infections. People with HIV/AIDS are less likely to get ''Pneumocystis'' pneumonia as a result of antiretroviral therapy (ART). However, ''Pneumocystis'' pneumonia is still a substantial public health problem. Most of what is scientifically known about ''Pneumocystis'' pneumonia and its treatment comes from studying people with HIV/AIDS.<ref name="cdc.gov" />

=== Susceptibility === Organisms against which trimethoprim/sulfamethoxazole can be effective include:<ref name="MSR">{{Cite web |title=trimethoprim/sulfamethoxazole (Rx) |url=http://reference.medscape.com/drug/bactrim-trimethoprim-sulfamethoxazole-342543#showall |url-status=live |archive-url=https://web.archive.org/web/20140116124927/http://reference.medscape.com/drug/bactrim-trimethoprim-sulfamethoxazole-342543#showall |archive-date=16 January 2014 |access-date=13 January 2014 |website=Medscape Reference}}</ref><ref name="Drugs" /> {{div col|colwidth=20em}} * ''Acinetobacter'' spp. * ''Aeromonas'' spp. * ''Alcaligenes''/''Achromobacter'' spp. * ''Bartonella henselae'' * ''Bordetella pertussis'' (pertussis) * ''Brucella'' spp. * ''Burkholderia cepacia'' * ''Burkholderia mallei'' (glanders) * ''Burkholderia pseudomallei'' (melioidosis) * ''Chlamydia'' spp. * ''Chryseobacterium meningosepticum'' * ''Citrobacter'' spp. * ''Enterobacter'' spp. * ''Enterococcus'' spp. * ''Escherichia coli'' * ''Haemophilus spp.'' * ''Hafnia alvei'' * ''Kingella'' spp. * ''Klebsiella granulomatis'' * ''Klebsiella pneumoniae'' * ''Legionella'' spp. * ''Listeria monocytogenes'' (listeriosis) * ''Moraxella catarrhalis'' * ''Morganella morganii'' * ''Mycobacterium tuberculosis'' (tuberculosis) * ''Neisseria gonorrhoeae'' (gonorrhoea) * ''Neisseria meningitidis'' (meningococcal disease) * ''Nocardia'' spp. * ''Plesiomonas shigelloides'' * ''Pneumocystis jirovecii'' * ''Proteus mirabilis'' * ''Proteus vulgaris'' * ''Providencia rettgeri'' * ''Providencia stuartii'' * ''Salmonella typhi'' (typhoid fever) * Non-typhi (food poisoning) ''Salmonella'' * ''Serratia'' spp. * ''Shigella'' spp. * ''Staphylococcus aureus'' * ''Staphylococcus epidermidis'' * ''Staphylococcus saprophyticus'' * ''Stenotrophomonas maltophilia'' * ''Streptococcus agalactiae'' * ''Streptococcus pneumoniae'' * ''Streptococcus pyogenes'' * ''Streptococcus viridans'' * ''Toxoplasma gondii'' (toxoplasmosis) * ''Tropheryma whippelii'' (Whipple's disease) * ''Vibrio cholerae'' (cholera) * ''Yersinia enterocolitica'' * ''Yersinia pestis'' (bubonic plague) * ''Yersinia pseudotuberculosis'' {{div col end}}

The only notable nonsusceptible organisms are ''Pseudomonas aeruginosa'', the mycoplasmae<ref name="Drugs" /> and ''Francisella tularensis'' (the causative organism of tularaemia).<ref>{{Cite web |date=17 July 2011 |title=Tularemia |url=http://new.dhh.louisiana.gov/assets/oph/Center-PHCH/Center-CH/infectious-epi/EpiManual/TularemiaManual.pdf |url-status=live |archive-url=https://web.archive.org/web/20140223030105/http://new.dhh.louisiana.gov/assets/oph/Center-PHCH/Center-CH/infectious-epi/EpiManual/TularemiaManual.pdf |archive-date=23 February 2014 |access-date=12 February 2014 |website=Infectious Disease Epidemiology Section |publisher=Louisiana Office of Public Health}}</ref><ref>{{Cite journal |vauthors=Harik NS |date=July 2013 |title=Tularemia: epidemiology, diagnosis, and treatment |journal=Pediatric Annals |volume=42 |issue=7 |pages=288–292 |doi=10.3928/00904481-20130619-13 |pmid=23805970}}</ref>

=== Pregnancy and breast feeding === Its use during pregnancy is contraindicated, although it has been placed in Australian pregnancy category C.<ref name="MSR" /> Its use during the first trimester (during organogenesis) and 12 weeks prior to pregnancy has been associated with an increased risk of congenital malformations, especially malformations associated with maternal folic acid deficiency (which is most likely related to the mechanism of action of co-trimoxazole) such as neural tube defects such as spina bifida, cardiovascular malformations (e.g. Ebstein's anomaly), urinary tract defects, oral clefts, and club foot in epidemiological studies.<ref name="MSR" /> Its use later on during pregnancy also increases the risk of preterm labour (odds ratio: 1.51) and low birth weight (odds ratio: 1.67).<ref>{{Cite journal |vauthors=Yang J, Xie RH, Krewski D, Wang YJ, Walker M, Wen SW |date=May 2011 |title=Exposure to trimethoprim/sulfamethoxazole but not other FDA category C and D anti-infectives is associated with increased risks of preterm birth and low birth weight |journal=International Journal of Infectious Diseases |volume=15 |issue=5 |pages=e336–e341 |doi=10.1016/j.ijid.2011.01.007 |pmid=21345707 |doi-access=free |title-link=doi}}</ref><ref>{{Cite journal |vauthors=Santos F, Sheehy O, Perreault S, Ferreira E, Berard A |date=October 2011 |title=Exposure to anti-infective drugs during pregnancy and the risk of small-for-gestational-age newborns: a case-control study |journal=BJOG |volume=118 |issue=11 |pages=1374–1382 |doi=10.1111/j.1471-0528.2011.03041.x |pmid=21749628 |s2cid=21014782 |doi-access=free |title-link=doi}}</ref> Animal studies have yielded similarly discouraging results.<ref name="TGA" />

It appears to be safe for use during breastfeeding as long as the baby is healthy.<ref name="Preg2015">{{Cite web |title=Sulfamethoxazole / trimethoprim Pregnancy and Breastfeeding Warnings |url=https://www.drugs.com/pregnancy/sulfamethoxazole-trimethoprim.html |url-status=live |archive-url=https://web.archive.org/web/20150906073951/http://www.drugs.com/pregnancy/sulfamethoxazole-trimethoprim.html |archive-date=6 September 2015 |access-date=31 August 2015 |quote=An extensive systematic review of sulfonamide usage near term and during breastfeeding found no side effects in infants; the authors concluded that use of this combination drug during breastfeeding presents no risk of neonatal kernicterus... LactMed: Use is considered acceptable when breastfeeding healthy, full-term infants after the newborn period}}</ref>

=== Infants === Its use in those less than 2 months of age is not recommended due to the risk of adverse side effects.<ref>{{Cite web |title=Drugs & Medications |url=https://www.webmd.com/drugs/2/drug-5530/bactrim-ds-oral/details/list-sideeffects |url-status=live |archive-url=https://web.archive.org/web/20190419210051/https://www.webmd.com/drugs/2/drug-5530/bactrim-ds-oral/details/list-sideeffects |archive-date=19 April 2019 |access-date=19 April 2019 |website=WebMD}}</ref>

== Adverse effects == {{See also|List of side effects of trimethoprim/sulfamethoxazole}}

Common side effects include nausea, vomiting, rash, and diarrhea.<ref name="AHFS2015" /> Severe allergic reactions and ''Clostridioides difficile'' infection may occasionally occur.<ref name="AHFS2015" /> Its use in pregnancy is not recommended.<ref name="AHFS2015" /><ref name="Preg2015" /> It appears to be safe for use during breastfeeding as long as the baby is healthy.<ref name="Preg2015" />

A recent study supported previous case reports that the treatment of teens or young adults with trimethoprim/sulfamethoxazole can cause serious adverse results. The study found that the 30-day risk of developing potentially lethal respiratory failure in patients aged 10 to 25 years who were treated with trimethoprim/sulfamethoxazole was significantly higher than those in this age group who were treated with either amoxicillin or a cephalosporin. These findings supported the FDA warning on using trimethoprim/sulfamethoxazole. Overall, the study suggested that this risk of respiratory failure should be carefully weighed against the benefits of using this trimethoprim/sulfamethoxazole drug combination in individuals 10 to 25 years old.<ref name="pmid41284296">{{cite journal | vauthors = Ahmadi F, McArthur E, Garcia-Bournissen F, Rieder MJ, Muanda FT | title = Trimethoprim-Sulfamethoxazole and Acute Respiratory Failure in Adolescents and Young Adults | journal = JAMA Network Open | volume = 8 | issue = 11 | pages = e2545251 | date = November 2025 | pmid = 41284296 | pmc = 12645330 | doi = 10.1001/jamanetworkopen.2025.45251 | url = }}</ref>

== Contraindications == Contraindications include the following:<ref name="MSR" /><ref name="Co-Trimoxazole SmPC" />

{{div col|colwidth=36em}} * Known hypersensitivity to trimethoprim, sulphonamides or any other ingredients in the formulations * Pregnancy * Severe liver failure, marked liver parenchymal damage, or jaundice. * Serious haematological disorders and porphyria (due to the sulfonamide component of the preparation). * Severe chronic kidney disease (CrCl <15 ml/min) where repeated measurements of the plasma concentration cannot be performed {{div col end}}

== Interactions == Its use is advised against in people being concomitantly treated with:<ref name="MSR" /><ref name="TGA" /><ref name="Co-Trimoxazole SmPC" /><ref name="Bactrim FDA label" /><ref name="BNF">{{Cite book |last=Joint Formulary Committee |url=https://archive.org/details/bnf65britishnati0000unse |title=British National Formulary (BNF) |publisher=Pharmaceutical Press |year=2013 |isbn=978-0-85711-084-8 |edition=65 |location=London, UK |url-access=registration}}</ref><ref name="AMH">{{Cite book |title=Australian Medicines Handbook |publisher=The Australian Medicines Handbook Unit Trust |year=2013 |isbn=978-0-9805790-9-3 |veditors=Rossi S |edition=2013 |location=Adelaide}}</ref>

{{div col|colwidth=36em}} * ACE inhibitors like captopril, enalapril, lisinopril, perindopril, and ramipril due to the potential for additive hyperkalaemic effects<ref name="Co-Trimoxazole SmPC" /> * Prilocaine — additive risk of methaemoglobinaemia * Antiarrhythmics like amiodarone (increased risk of ventricular arrhythmias) and dofetilide (increased risk of QT interval prolongation) * Antibacterials like dapsone (increases plasma levels of both drugs), methenamine (increased risk of crystalluria) and rifampicin (as it may lead to an increased plasma level of rifampicin and lower plasma levels of trimethoprim) * Anticoagulants like warfarin and acenocoumarol — anticoagulant effects of either drug is potentiated by this combination * Sulfonylureas — effects enhanced * Phenytoin, half-life of phenytoin is increased * Antifolates like pyrimethamine, proguanil and methotrexate increase the risk of associated side effects like bone marrow toxicity, folic acid supplementation should be considered. A significant risk of megaloblastic anaemia exists with doses of pyrimethamine in excess of 25 mg/wk. * Antivirals, more specifically, lamivudine (increased plasma concentrations of lamivudine), zalcitabine (increased plasma concentrations of zalcitabine) and zidovudine (increased risk of haematological reactions) * Procainamide and/or amantadine may have their plasma concentrations increased bilaterally or unilaterally. * Clozapine and other antipsychotics — increased risk of haematological side effects * Nucleoside analogue antineoplastics like azathioprine and mercaptopurine — increased risk of haematological toxicity * Digoxin — increase in digoxin levels in a proportion of elderly patients * Diuretics — elderly patients receiving thiazide diuretics are at a heightened risk for developing thrombocytopaenia while on co-trimoxazole * Ciclosporin — patients who have received a kidney transplant and are receiving co-trimoxazole and ciclosporin concomitantly are at an increased risk of having a reversible deterioration in their kidney function. * Spironolactone — concurrent use can increase the likelihood of hyperkalemia, especially in the elderly. The trimethoprim portion acts to prevent potassium excretion in the distal tubule of the nephron.<ref name="pmid24156179">{{Cite journal |vauthors=Juvet T, Gourineni VC, Ravi S, Zarich SW |date=September 2013 |title=Life-threatening hyperkalemia: a potentially lethal drug combination |journal=Connecticut Medicine |volume=77 |issue=8 |pages=491–3 |pmid=24156179}}</ref> * Potassium aminobenzoate — effects of sulfonamides (like Sulfamethoxazole) inhibited. * Laboratory tests — trimethoprim and sulfonamides have been reported to interfere with diagnostic tests, including serum-methotrexate and elevated serum creatinine levels,<ref name="Gentry_2013">{{Cite journal |vauthors=Gentry CA, Nguyen AT |date=December 2013 |title=An evaluation of hyperkalemia and serum creatinine elevation associated with different dosage levels of outpatient trimethoprim-sulfamethoxazole with and without concomitant medications |journal=The Annals of Pharmacotherapy |volume=47 |issue=12 |pages=1618–26 |doi=10.1177/1060028013509973 |pmid=24259630 |s2cid=19395548}}</ref> also urea, urinary glucose and urobilinogen tests. {{div col end}}

=== Overdose === Likely signs of toxicity include:<ref name="TGA" /> {{div col|colwidth=14em}} * Nausea * Vomiting * Dizziness * Headache * Mental depression * Confusion * Thrombocytopenia * Uremia * Bone marrow depression * Loss of appetite * Colic * Drowsiness * Unconsciousness {{div col end}}

The recommended treatment for overdose includes:<ref name="TGA" /> * Administration of activated charcoal * Stomach pumping * General supportive measures * Haemodialysis, which is moderately effective in clearing co-trimoxazole from the plasma. * Calcium folinate treatment in cases of blood dyscrasias * Forcing oral fluids Alkalinisation of the urine may reduce the toxicity of sulfamethoxazole, but it may increase the toxic effects of trimethoprim.<ref name="TGA" />

== Pharmacology == class=skin-invert-image|thumb|300px|Tetrahydrofolate synthesis pathway

The synergy between trimethoprim and sulfamethoxazole was first described in the late 1960s.<ref>{{Cite journal |vauthors=Bushby SR, Hitchings GH |date=May 1968 |title=Trimethoprim, a sulphonamide potentiator |journal=British Journal of Pharmacology and Chemotherapy |volume=33 |issue=1 |pages=72–90 |doi=10.1111/j.1476-5381.1968.tb00475.x |pmc=1570262 |pmid=5301731}}</ref><ref>{{Cite journal |vauthors=Böhni E |year=1969 |title=[Comparative bacteriological investigations with the combination trimethoprim/sulfamethoxazole in vitro and in vivo] |journal=Chemotherapy |volume=14 |issue=Suppl |pages=Suppl:1–Suppl21 |doi=10.1159/000220651 |pmid=4908562}}</ref><ref>{{Cite journal |vauthors=Böhni E |date=November 1969 |title=Chemotherapeutic activity of the combination of trimethoprim and sulphamethoxazole in infections of mice |journal=Postgraduate Medical Journal |volume=45 |issue=Suppl |pages=Suppl:18–Suppl:21 |pmid=4902845}}</ref> Trimethoprim and sulfamethoxazole have a greater effect when given together than when given separately, because they inhibit successive steps in the folate synthesis pathway. They are given in a one-to-five ratio in their tablet formulations so that when they enter the body their concentration in the blood and tissues is roughly one-to-twenty — the exact ratio required for a peak synergistic effect between the two.<ref name="Drugs" />

Sulfamethoxazole, a sulfonamide, induces its therapeutic effects by interfering with the ''de novo'' (that is, from within the cell) synthesis of folate inside microbial organisms such as protozoa, fungi and bacteria. It does this by competing with ''p''-aminobenzoic acid (PABA) in the biosynthesis of dihydrofolate.<ref name="Drugs" />

Trimethoprim serves as a competitive inhibitor of dihydrofolate reductase (DHFR), hence inhibiting the ''de novo'' synthesis of tetrahydrofolate, the biologically active form of folate.<ref name="Drugs" />

Tetrahydrofolate is crucial in the synthesis of purines, thymidine, and methionine which are needed for the production of DNA and proteins<ref>{{Cite web |title=Tetrahydrofolic acid |url=https://pubchem.ncbi.nlm.nih.gov/compound/tetrahydrofolate#section=Drug-and-Medication-Information |url-status=live |archive-url=https://web.archive.org/web/20180226151952/https://pubchem.ncbi.nlm.nih.gov/compound/tetrahydrofolate#section=Drug-and-Medication-Information |archive-date=26 February 2018 |access-date=26 February 2018 |website=PubChem |publisher=U.S. National Library of Medicine}}</ref> during bacterial replication.

The effects of trimethoprim causes a backlog of dihydrofolate (DHF) and this backlog can work against the inhibitory effect the drug has on tetrahydrofolate biosynthesis. This is where the sulfamethoxazole comes in; its role is in depleting the excess DHF by preventing it from being synthesised in the first place.<ref name="Drugs" />

Co-trimoxazole was claimed to be more effective than either of its components individually in treating bacterial infections, although this was later disputed.<ref>{{Cite book |url=https://www.taylorfrancis.com/books/edit/10.1201/9781498747967/kucers-use-antibiotics-lindsay-grayson-sara-cosgrove-suzanne-crowe-lindsay-grayson-william-hope-james-mccarthy-john-mills-johan-mouton-david-paterson |title=Kucers' the Use of Antibiotics |vauthors=Trubiano JA, Grayson ML |publisher=CRC Press |year=2017 |isbn=978-1-4987-4796-7 |veditors=Grayson ML, Cosgrove S, Crowe S, Hope W, McCarthy J, Mills J, Mouton JW, Paterson D |edition=7th |pages=1625, 1634 |chapter=Trimethoprim and Trimethoprim–Sulfamethoxazole (Cotrimoxazole) |doi=10.1201/9781498747967 |chapter-url=https://www.taylorfrancis.com/chapters/edit/10.1201/9781498747967-92/trimethoprim-trimethoprim%E2%80%93sulfamethoxazole-cotrimoxazole-jason-trubiano-lindsay-grayson}}</ref><ref>{{Cite journal |vauthors=Brumfitt W, Hamilton-Miller JM |date=December 1993 |title=Reassessment of the rationale for the combinations of sulphonamides with diaminopyrimidines |journal=Journal of Chemotherapy |volume=5 |issue=6 |pages=465–469 |doi=10.1080/1120009X.1993.11741097 |pmid=8195839}}</ref>

{| class = wikitable |+ Pharmacokinetics of co-trimoxazole<ref name="MSR" /><ref name="TGA" /> ! Component !! Tmax (h) !! Vd (L) !! Protein binding !! t1/2 (h) ||Excretion |- | Sulfamethoxazole || 1-4 || 20 || 66% || 8-10 || Renal |- | Trimethoprim || 1-4 || 130 || 42-45% || 10 || Renal |}

== Society and culture ==

=== Legal status === {| class="wikitable" |+ <big>Indications for co-trimoxazole</big> ! scope="col" | Indication ! scope="col" | {{flagicon|USA}} FDA-labelled indication? ! scope="col" | {{flagicon|AUS}} TGA-labelled indication? ! scope="col" | {{flagicon|GBR}} MHRA-labelled indication? ! scope="col" style="text-align: left;" | Literature support |- | Acute infective exacerbation of COPD || {{Yes}} || {{No}} || {{No}} || Clinical trials are lacking. |- | Prophylaxis in HIV-infected individuals || {{No}} || {{No}} || {{No}} || Effective in one Ugandan study on morbidity, mortality, CD4-cell count, and viral load in HIV infection.<ref>{{Cite journal |vauthors=Mermin J, Lule J, Ekwaru JP, Malamba S, Downing R, Ransom R, Kaharuza F, Culver D, Kizito F, Bunnell R, Kigozi A, Nakanjako D, Wafula W, Quick R |date=October 2004 |title=Effect of co-trimoxazole prophylaxis on morbidity, mortality, CD4-cell count, and viral load in HIV infection in rural Uganda |url=https://zenodo.org/record/1259795 |url-status=live |journal=Lancet |volume=364 |issue=9443 |pages=1428–1434 |doi=10.1016/S0140-6736(04)17225-5 |pmid=15488218 |s2cid=23402992 |archive-url=https://web.archive.org/web/20210118194652/https://zenodo.org/record/1259795 |archive-date=18 January 2021 |access-date=12 September 2020}}</ref> |- | Otitis media || {{Yes|Pediatric population only}} || {{No}} || {{Yes}} || Clinical trials have confirmed its efficacy in chronic active<ref>{{Cite journal |vauthors=van der Veen EL, Rovers MM, Albers FW, Sanders EA, Schilder AG |date=May 2007 |title=Effectiveness of trimethoprim/sulfamethoxazole for children with chronic active otitis media: a randomized, placebo-controlled trial |journal=Pediatrics |volume=119 |issue=5 |pages=897–904 |doi=10.1542/peds.2006-2787 |pmid=17473089 |s2cid=23835227 |hdl-access=free |hdl=1874/25986}}</ref> and acute otitis media.<ref>{{Cite journal |vauthors=Leiberman A, Leibovitz E, Piglansky L, Raiz S, Press J, Yagupsky P, Dagan R |date=March 2001 |title=Bacteriologic and clinical efficacy of trimethoprim-sulfamethoxazole for treatment of acute otitis media |journal=The Pediatric Infectious Disease Journal |volume=20 |issue=3 |pages=260–264 |doi=10.1097/00006454-200103000-00009 |pmid=11303827 |s2cid=45262990}}</ref> |- | Travelers' diarrhea, treatment & prophylaxis || {{Yes}} || {{No}} || {{No}} || Clinical trials have confirmed its efficacy as a treatment for travellers' diarrhea.<ref>{{Cite journal |vauthors=Ericsson CD, Johnson PC, Dupont HL, Morgan DR, Bitsura JA, de la Cabada FJ |date=February 1987 |title=Ciprofloxacin or trimethoprim-sulfamethoxazole as initial therapy for travelers' diarrhea. A placebo-controlled, randomized trial |journal=Annals of Internal Medicine |volume=106 |issue=2 |pages=216–220 |doi=10.7326/0003-4819-106-2-216 |pmid=3541724}}</ref><ref>{{Cite journal |vauthors=Ericsson CD, DuPont HL, Mathewson JJ, West MS, Johnson PC, Bitsura JA |date=January 1990 |title=Treatment of traveler's diarrhea with sulfamethoxazole and trimethoprim and loperamide |journal=JAMA |volume=263 |issue=2 |pages=257–261 |doi=10.1001/jama.1990.03440020091039 |pmid=2403603}}</ref><ref>{{Cite journal |vauthors=Rendi-Wagner P, Kollaritsch H |date=March 2002 |title=Drug prophylaxis for travelers' diarrhea |journal=Clinical Infectious Diseases |volume=34 |issue=5 |pages=628–633 |doi=10.1086/338640 |pmid=11803509 |doi-access=free |title-link=doi}}</ref> |- | Urinary tract infection || {{Yes}} || {{No}} || {{Yes}} || Clinical trials have confirmed its efficacy in this indication.<ref name="Drugs">{{Cite journal |vauthors=Wormser GP, Keusch GT, Heel RC |date=December 1982 |title=Co-trimoxazole (trimethoprim-sulfamethoxazole): an updated review of its antibacterial activity and clinical efficacy |journal=Drugs |volume=24 |issue=6 |pages=459–518 |doi=10.2165/00003495-198224060-00002 |pmid=6759092 |s2cid=209121818}}</ref> |- | colspan="5" align="center" | '''<big>Bacterial infections</big>''' |- | Acne vulgaris || {{No}} || {{No}} || {{No}} || At least one clinical trial supports its use in this indication.<ref>{{Cite journal |vauthors=Nordin K, Hallander H, Fredriksson T, Rylander C |year=1978 |title=A clinical and bacteriological evaluation of the effect of sulphamethoxazole-trimethoprim in acne vulgaris, resistant to prior therapy with tetracyclines |journal=Dermatologica |volume=157 |issue=4 |pages=245–253 |doi=10.1159/000250840 |pmid=150980}}</ref> |- | Listeria || {{No}} || {{Yes}} || {{No}} || Well-designed clinical trials are lacking. |- | Melioidosis || {{No}} || {{Yes}} || {{No}} || Clinical trials have confirmed its efficacy, with or without adjunctive doxycycline; although, co-trimoxazole alone seems preferable.<ref>{{Cite journal |vauthors=Chetchotisakd P, Chaowagul W, Mootsikapun P, Budhsarawong D, Thinkamrop B |date=January 2001 |title=Maintenance therapy of melioidosis with ciprofloxacin plus azithromycin compared with cotrimoxazole plus doxycycline |journal=The American Journal of Tropical Medicine and Hygiene |volume=64 |issue=1–2 |pages=24–27 |doi=10.4269/ajtmh.2001.64.24 |pmid=11425157}}</ref><ref>{{Cite journal |vauthors=Chusri S, Hortiwakul T, Charoenmak B, Silpapojakul K |date=November 2012 |title=Outcomes of patients with melioidosis treated with cotrimoxazole alone for eradication therapy |journal=The American Journal of Tropical Medicine and Hygiene |volume=87 |issue=5 |pages=927–932 |doi=10.4269/ajtmh.2012.12-0136 |pmc=3516270 |pmid=23033403}}</ref><ref>{{Cite journal |vauthors=Chetchotisakd P, Chierakul W, Chaowagul W, Anunnatsiri S, Phimda K, Mootsikapun P, Chaisuksant S, Pilaikul J, Thinkhamrop B, Phiphitaporn S, Susaengrat W, Toondee C, Wongrattanacheewin S, Wuthiekanun V, Chantratita N, Thaipadungpanit J, Day NP, Limmathurotsakul D, Peacock SJ |date=March 2014 |title=Trimethoprim-sulfamethoxazole versus trimethoprim-sulfamethoxazole plus doxycycline as oral eradicative treatment for melioidosis (MERTH): a multicentre, double-blind, non-inferiority, randomised controlled trial |journal=Lancet |volume=383 |issue=9919 |pages=807–814 |doi=10.1016/S0140-6736(13)61951-0 |pmc=3939931 |pmid=24284287}}</ref> |- | Pertussis (whooping cough) || {{No}} || {{No}} || {{No}} || One Cochrane review supports its efficacy in preventing the spread of pertussis.<ref>{{Cite journal |vauthors=Altunaiji S, Kukuruzovic R, Curtis N, Massie J |date=July 2007 |title=Antibiotics for whooping cough (pertussis) |journal=The Cochrane Database of Systematic Reviews |volume=2013 |issue=3 |article-number=CD004404 |doi=10.1002/14651858.CD004404.pub3 |pmc=11322855 |pmid=17636756}}</ref> |- | Shigellosis || {{Yes}} || {{Yes}} || {{No}} || Generally accepted treatment for shigellosis.<ref>{{Cite web |date=25 June 2012 |title=''Shigella'' Infection Medication |url=http://emedicine.medscape.com/article/968773-medication#showall |url-status=live |archive-url=https://web.archive.org/web/20140108135323/http://emedicine.medscape.com/article/968773-medication#showall |archive-date=8 January 2014 |access-date=8 January 2014 |website=Medscape Reference |publisher=WebMD |vauthors=Sureshbabu J, Venugopalan P, Abuhammour W |veditors=Fennelly G, Windle ML, Lutwick LI, Tolan Jr RW, Steele RW}}</ref> A Cochrane review found that while it is an effective treatment for shigellosis it also produces more significant adverse effects than other antibiotic drugs.<ref>{{Cite journal |vauthors=Christopher PR, David KV, John SM, Sankarapandian V |date=August 2010 |title=Antibiotic therapy for Shigella dysentery |journal=The Cochrane Database of Systematic Reviews |volume=2010 |issue=8 |article-number=CD006784 |doi=10.1002/14651858.CD006784.pub4 |pmc=6532574 |pmid=20687081}}</ref> |- | ''Staphylococcus aureus'' infections || {{No}} || {{No}} || {{No}} || ''In vitro'' and ''in vivo'' activity against both non-resistant and methicillin-resistant ''Staphylococcus aureus'' (MRSA) infections.<ref>{{Cite journal |vauthors=Grim SA, Rapp RP, Martin CA, Evans ME |date=February 2005 |title=Trimethoprim-sulfamethoxazole as a viable treatment option for infections caused by methicillin-resistant Staphylococcus aureus |journal=Pharmacotherapy |volume=25 |issue=2 |pages=253–264 |doi=10.1592/phco.25.2.253.56956 |pmid=15767239 |s2cid=31546680}}</ref><ref>{{Cite journal |vauthors=Cenizal MJ, Skiest D, Luber S, Bedimo R, Davis P, Fox P, Delaney K, Hardy RD |date=July 2007 |title=Prospective randomized trial of empiric therapy with trimethoprim-sulfamethoxazole or doxycycline for outpatient skin and soft tissue infections in an area of high prevalence of methicillin-resistant Staphylococcus aureus |journal=Antimicrobial Agents and Chemotherapy |volume=51 |issue=7 |pages=2628–2630 |doi=10.1128/AAC.00206-07 |pmc=1913240 |pmid=17502411}}</ref><ref>{{Cite journal |vauthors=LaPlante KL, Leonard SN, Andes DR, Craig WA, Rybak MJ |date=June 2008 |title=Activities of clindamycin, daptomycin, doxycycline, linezolid, trimethoprim-sulfamethoxazole, and vancomycin against community-associated methicillin-resistant Staphylococcus aureus with inducible clindamycin resistance in murine thigh infection and in vitro pharmacodynamic models |journal=Antimicrobial Agents and Chemotherapy |volume=52 |issue=6 |pages=2156–2162 |doi=10.1128/AAC.01046-07 |pmc=2415789 |pmid=18411321}}</ref><ref>{{Cite journal |vauthors=Pappas G, Athanasoulia AP, Matthaiou DK, Falagas ME |date=April 2009 |title=Trimethoprim-sulfamethoxazole for methicillin-resistant Staphylococcus aureus: a forgotten alternative? |journal=Journal of Chemotherapy |volume=21 |issue=2 |pages=115–126 |doi=10.1179/joc.2009.21.2.115 |pmid=19423463 |s2cid=8425281}}</ref><ref>{{Cite journal |vauthors=Goldberg E, Paul M, Talker O, Samra Z, Raskin M, Hazzan R, Leibovici L, Bishara J |date=August 2010 |title=Co-trimoxazole versus vancomycin for the treatment of methicillin-resistant Staphylococcus aureus bacteraemia: a retrospective cohort study |journal=The Journal of Antimicrobial Chemotherapy |volume=65 |issue=8 |pages=1779–1783 |doi=10.1093/jac/dkq179 |pmid=20507860 |doi-access=free |title-link=doi}}</ref><ref>{{Cite journal |vauthors=Cadena J, Nair S, Henao-Martinez AF, Jorgensen JH, Patterson JE, Sreeramoju PV |date=December 2011 |title=Dose of trimethoprim-sulfamethoxazole to treat skin and skin structure infections caused by methicillin-resistant Staphylococcus aureus |journal=Antimicrobial Agents and Chemotherapy |volume=55 |issue=12 |pages=5430–5432 |doi=10.1128/AAC.00706-11 |pmc=3232808 |pmid=21930870}}</ref><ref>{{Cite journal |vauthors=Avery LM, Steed ME, Woodruff AE, Hasan M, Rybak MJ |date=November 2012 |title=Daptomycin-nonsusceptible vancomycin-intermediate staphylococcus aureus vertebral osteomyelitis cases complicated by bacteremia treated with high-dose daptomycin and trimethoprim-sulfamethoxazole |journal=Antimicrobial Agents and Chemotherapy |volume=56 |issue=11 |pages=5990–5993 |doi=10.1128/AAC.01046-12 |pmc=3486608 |pmid=22869580}}</ref> |- | Tuberculosis || {{No}} || {{No}} || {{No}} || ''In vitro'' and ''in vivo'' activity against both nonresistant and MDR strains of TB.<ref>{{Cite journal |vauthors=Forgacs P, Wengenack NL, Hall L, Zimmerman SK, Silverman ML, Roberts GD |date=November 2009 |title=Tuberculosis and trimethoprim-sulfamethoxazole |journal=Antimicrobial Agents and Chemotherapy |volume=53 |issue=11 |pages=4789–4793 |doi=10.1128/AAC.01658-08 |pmc=2772331 |pmid=19564358}}</ref><ref>{{Cite journal |vauthors=Vilchèze C, Jacobs WR |date=October 2012 |title=The combination of sulfamethoxazole, trimethoprim, and isoniazid or rifampin is bactericidal and prevents the emergence of drug resistance in Mycobacterium tuberculosis |journal=Antimicrobial Agents and Chemotherapy |volume=56 |issue=10 |pages=5142–5148 |doi=10.1128/AAC.00832-12 |pmc=3457372 |pmid=22825115}}</ref><ref>{{Cite journal |vauthors=Alsaad N, van Altena R, Pranger AD, van Soolingen D, de Lange WC, van der Werf TS, Kosterink JG, Alffenaar JW |date=August 2013 |title=Evaluation of co-trimoxazole in the treatment of multidrug-resistant tuberculosis |journal=The European Respiratory Journal |volume=42 |issue=2 |pages=504–512 |doi=10.1183/09031936.00114812 |pmid=23100498 |doi-access=free |title-link=doi}}</ref> |- | Whipple's disease || {{No}} || {{No}} || {{No}} || Co-trimoxazole is the recommended standard treatment for whipple's disease in some treatment protocols.<ref>{{Cite journal |vauthors=Fenollar F, Raoult D |date=January 2001 |title=Whipple's disease |journal=Clinical and Diagnostic Laboratory Immunology |volume=8 |issue=1 |pages=1–8 |doi=10.1128/CDLI.8.1.1-8.2001 |pmc=96003 |pmid=11139188}}</ref><ref>{{Cite journal |vauthors=Ojeda E, Cosme A, Lapaza J, Torrado J, Arruabarrena I, Alzate L |date=February 2010 |title=Whipple's disease in Spain: a clinical review of 91 patients diagnosed between 1947 and 2001 |journal=Revista Española de Enfermedades Digestivas |volume=102 |issue=2 |pages=108–123 |doi=10.4321/s1130-01082010000200006 |pmid=20361847 |doi-access=free |title-link=doi}}</ref><ref>{{Cite journal |vauthors=Puéchal X |date=November 2013 |title=Whipple's disease |journal=Postgraduate Medical Journal |volume=89 |issue=1057 |pages=659–665 |doi=10.1136/postgradmedj-2012-202684rep |pmid=24129033 |s2cid=24695700}}</ref> |- | colspan="5" align="center" | '''<big>Fungal and protozoal infections</big>''' |- | Isosporiasis || {{No}} || {{No}} || {{No}} || Clinical trials have confirmed its use in this indication.<ref name="pmid18257775">{{Cite journal |vauthors=Lagrange-Xélot M, Porcher R, Sarfati C, de Castro N, Carel O, Magnier JD, Delcey V, Molina JM |date=February 2008 |title=Isosporiasis in patients with HIV infection in the highly active antiretroviral therapy era in France |journal=HIV Medicine |volume=9 |issue=2 |pages=126–130 |doi=10.1111/j.1468-1293.2007.00530.x |pmid=18257775 |s2cid=26120155 |doi-access=free |title-link=doi}}</ref> |- | Malaria || {{No}} || {{No}} || {{No}} || Clinical trials have confirmed its efficacy in both the treatment and prevention of malaria.<ref>{{Cite journal |vauthors=Manyando C, Njunju EM, D'Alessandro U, Van Geertruyden JP |year=2013 |title=Safety and efficacy of co-trimoxazole for treatment and prevention of Plasmodium falciparum malaria: a systematic review |journal=PLOS ONE |volume=8 |issue=2 |article-number=e56916 |bibcode=2013PLoSO...856916M |doi=10.1371/journal.pone.0056916 |pmc=3579948 |pmid=23451110 |doi-access=free |title-link=doi}}</ref> |- | ''Pneumocystis jirovecii'' pneumonia || {{Yes}} || {{Yes}} || {{Yes}} || Its use as a prophylactic treatment is supported by one clinical trial involving children with acute lymphoblastic leukaemia.<ref>{{Cite journal |vauthors=Agrawal AK, Chang PP, Feusner J |date=January 2011 |title=Twice weekly Pneumocystis jiroveci pneumonia prophylaxis with trimethoprim-sulfamethoxazole in pediatric patients with acute lymphoblastic leukemia |journal=Journal of Pediatric Hematology/Oncology |volume=33 |issue=1 |pages=e1–e4 |doi=10.1097/MPH.0b013e3181fd6fca |pmid=21102354 |s2cid=42371307}}</ref> Other than this and one other clinical trial into its efficacy as a treatment for ''pneumocystis'' pneumonia,<ref>{{Cite journal |vauthors=Safrin S, Finkelstein DM, Feinberg J, Frame P, Simpson G, Wu A, Cheung T, Soeiro R, Hojczyk P, Black JR |date=May 1996 |title=Comparison of three regimens for treatment of mild to moderate Pneumocystis carinii pneumonia in patients with AIDS. A double-blind, randomized, trial of oral trimethoprim-sulfamethoxazole, dapsone-trimethoprim, and clindamycin-primaquine. ACTG 108 Study Group |journal=Annals of Internal Medicine |volume=124 |issue=9 |pages=792–802 |doi=10.7326/0003-4819-124-9-199605010-00003 |pmid=8610948 |s2cid=40999772}}</ref> data on its use in both the treatment and prevention of ''pneumocystis'' pneumonia is significantly lacking. |- | Toxoplasmosis || {{Yes}} || {{Yes|Prevention only}} || {{Yes}} || Clinical trials have confirmed its prophylactic and therapeutic utility in cases of toxoplasmosis.<ref>{{Cite journal |vauthors=Canessa A, Del Bono V, De Leo P, Piersantelli N, Terragna A |date=February 1992 |title=Cotrimoxazole therapy of Toxoplasma gondii encephalitis in AIDS patients |journal=European Journal of Clinical Microbiology & Infectious Diseases |volume=11 |issue=2 |pages=125–130 |doi=10.1007/BF01967063 |pmid=1396726 |s2cid=13621055}}</ref><ref>{{Cite journal |vauthors=Torre D, Casari S, Speranza F, Donisi A, Gregis G, Poggio A, Ranieri S, Orani A, Angarano G, Chiodo F, Fiori G, Carosi G |date=June 1998 |title=Randomized trial of trimethoprim-sulfamethoxazole versus pyrimethamine-sulfadiazine for therapy of toxoplasmic encephalitis in patients with AIDS. Italian Collaborative Study Group |journal=Antimicrobial Agents and Chemotherapy |volume=42 |issue=6 |pages=1346–1349 |doi=10.1128/AAC.42.6.1346 |pmc=105601 |pmid=9624473}}</ref><ref>{{Cite journal |vauthors=Muñoz P, Arencibia J, Rodríguez C, Rivera M, Palomo J, Yañez J, Bouza E |date=April 2003 |title=Trimethoprim-sulfamethoxazole as toxoplasmosis prophylaxis for heart transplant recipients |journal=Clinical Infectious Diseases |volume=36 |issue=7 |pages=932–3; author reply 933 |doi=10.1086/368209 |pmid=12652396 |doi-access=free |title-link=doi}}</ref><ref>{{Cite journal |vauthors=Béraud G, Pierre-François S, Foltzer A, Abel S, Liautaud B, Smadja D, Cabié A |date=April 2009 |title=Cotrimoxazole for treatment of cerebral toxoplasmosis: an observational cohort study during 1994–2006 |journal=The American Journal of Tropical Medicine and Hygiene |volume=80 |issue=4 |pages=583–587 |doi=10.4269/ajtmh.2009.80.583 |pmid=19346380 |s2cid=22240685 |doi-access=free}}</ref><ref>{{Cite journal |vauthors=Alavi SM, Alavi L |date=September 2010 |title=Treatment of toxoplasmic lymphadenitis with co-trimoxazole: double-blind, randomized clinical trial |journal=International Journal of Infectious Diseases |volume=14 |issue=Supplement 3 |pages=e67–e69 |doi=10.1016/j.ijid.2009.11.015 |pmid=20194044 |doi-access=free |title-link=doi}}</ref><ref>{{Cite journal |vauthors=Patil HV, Patil VC, Rajmane V, Raje V |date=January 2011 |title=Successful treatment of cerebral toxoplasmosis with cotrimoxazole |journal=Indian Journal of Sexually Transmitted Diseases and AIDS |volume=32 |issue=1 |pages=44–46 |doi=10.4103/0253-7184.81255 |pmc=3139289 |pmid=21799577 |doi-access=free}}</ref> |- |}

=== Brand names === Trimethoprim/sulfamethoxazole may be abbreviated as SXT, SMZ-TMP, TMP-SMX, TMP-SMZ, or TMP-sulfa.{{citation needed|date=December 2021}} The generic British Approved Name (BAN) Co-trimoxazole is used for trimethoprim/sulfamethoxazole manufactured and sold by many different companies.<ref>{{Cite web |title=Co-trimoxazole Medicinal forms |url=https://bnf.nice.org.uk/drugs/co-trimoxazole/medicinal-forms/#oral-tablet |access-date=4 June 2024 |publisher=NICE}}</ref>

The following list of brand names is incomplete:

{{div col|colwidth=22em}} * Bactrim, Bactrimel (manufactured by Roche and distributed in Europe) * Bactrom (Venezuela) * Bibactin (manufactured by PPM and distributed in Cambodia and some African countries) * Biseptol * Sumetrolim * Co-trimoxazole (used as generic UK name) * Cotrim * Deprim (AFT Pharmaceuticals) * Diseptyl (Israel) * Graprima Forte Kaplet (manufactured by PT Graha Farma and distributed in Indonesia) * Infectrin, Bactrim (Brazil) * Novo-Trimel<ref name="Novo-Trimel">{{Cite web |title=Novo-Trimel Advanced Patient Information – Drugs.com |url=https://www.drugs.com/cons/novo-trimel.html |url-status=live |archive-url=https://web.archive.org/web/20180201192950/https://www.drugs.com/cons/novo-trimel.html |archive-date=1 February 2018 |access-date=1 February 2018 |website=Drugs.com}}</ref> * Primadex (manufactured by Dexa Medica and distributed in Indonesia) * Primotren (Lek in Slovenia and other countries) * Resprim * Sanprima (manufactured by Sanbe Farma and distributed in Indonesia) * Septra (Aspen Pharmacare and formerly GlaxoSmithKline) * Septram (Panama) * Septran (GlaxoSmithKline)<ref name="GSK2017">{{Cite web |date=13 August 2017 |title=Septran/Sepman Double Strength – Co-Trimoxazole Oral Formulations |url=http://india-pharma.gsk.com/media/701285/septran-and-sepmax.pdf |url-status=live |archive-url=https://web.archive.org/web/20180601211744/http://india-pharma.gsk.com/media/701285/septran-and-sepmax.pdf |archive-date=1 June 2018 |access-date=1 June 2018 |publisher=GlaxoSmithKline}}</ref> * Septrin (Spain)<ref>{{Cite web |title=SEPTRIN FORTE Comp. 800/160 mg – Datos generales |url=http://www.vademecum.es/medicamento-septrin+forte_3626 |url-status=live |archive-url=https://web.archive.org/web/20150616233203/http://www.vademecum.es/medicamento-septrin+forte_3626 |archive-date=16 June 2015 |access-date=17 August 2015}}</ref> * Sulfatrim * Teva-Trimel * Trisul * Vactrim (manufactured and distributed in Laos) {{div col end}}

=== Economics === Trimethoprim/sulfamethoxazole is relatively inexpensive as of 2019.<ref name="Brown2019">{{Cite book |url=https://books.google.com/books?id=_nTADwAAQBAJ&dq=Cefalexin+relatively+inexpensive&pg=PA1173 |title=Lewis's Medical-Surgical Nursing EBook: Assessment and Management of Clinical Problems |vauthors=Brown D, Edwards H, Buckley T, Aitken RL |date=2019 |publisher=Elsevier Health Sciences |isbn=978-0-7295-8708-2 |page=1173 |access-date=30 March 2020 |archive-url=https://web.archive.org/web/20210829095029/https://www.google.com/books/edition/Lewis_s_Medical_Surgical_Nursing_EBook/_nTADwAAQBAJ?hl=en&gbpv=1&dq=Cefalexin+relatively+inexpensive&pg=PA1173 |archive-date=29 August 2021 |url-status=live}}</ref>

== References == {{Reflist}}

{{DEFAULTSORT:Trimethoprim Sulfamethoxazole}} Category:Acetaldehyde dehydrogenase inhibitors Category:Combination antibiotics Category:Drugs developed by Pfizer Category:Drugs developed by GSK plc Category:Drugs developed by Novartis Category:Drugs developed by Hoffmann-La Roche Category:World Health Organization essential medicines Category:Wikipedia medicine articles ready to translate