The SIDP Podcast
10 months ago

#83 – Dosing Consult: Sulfamethoxazole/trimethoprim

Episode Notes

In what has been described on Twitter as the “doing your own taxes of medicine,” Drs. Emily Heil (@emilylheil) and Andrew Fratoni (@AFratty) join Dr. Jillian Hayes (@thejillianhayes) to break down the ins and outs of sulfamethoxazole/trimethoprim dosing! Tune in for a discussion on the use of this agent for methicillin-resistant Staphylococcus aureus, gram-negatives, pneumocystis, and Stenotrophomonas maltophilia.


  1. Twitter Thread re: Bactrim dosing:
  2. PJP OI Guidelines:
  3. IDSA Resistant Gram Negative Guidance Document:
  4. (Lower doses of PJP Treatment): Butler-Laporte G, Smyth E, Amar-Zifkin A, Cheng M, McDonald E, Lee T. Low-dose TMP-SMX in the Treatment of Pneumocystis jirovecii Pneumonia: A Systematic Review and Meta-Analysis. Open Forum Infectious Diseases, Volume 7, Issue 5, May 2020, ofaa112,
  5. (DS Vs SS for PJP PPX): Schneider MM, Nielsen TL, Nelsing S, et al. Efficacy and toxicity of two doses of trimethoprim-sulfamethoxazole as primary prophylaxis against Pneumocystis carinii pneumonia in patients with human immunodeficiency virus. Dutch AIDS Treatment Group. J Infect Dis. 1995;171(6):1632-1636. Available at:
  6. General Bactrim PK/PD: Trubiano JA, Grayson ML. Trimethoprim and Trimethoprim-Sulfamethoxazole (Cotrimoxazole). Chapter 92, Kucers’ The Use of Antibiotics (7th Edition). Taylor & Francis, 2017.
  7. (2014 IDSA SSTI Guidelines). PMID 24973422
  8. Cadena J, Nair S, Henao-Martinez AF, Jorgensen JH, Patterson JE, Sreeramoju PV. Dose of trimethoprim-sulfamethoxazole to treat skin and skin structure infections caused by methicillin-resistant Staphylococcus aureus. Antimicrob Agents Chemother. 2011 Dec;55(12):5430-2. doi: 10.1128/AAC.00706-11. Epub 2011 Sep 19. PMID: 21930870; PMCID: PMC3232808.
  9. Halilovic J, Heintz BH, Brown J. Risk factors for clinical failure in patients hospitalized with cellulitis and cutaneous abscess. J Infect. 2012 Aug;65(2):128-34. doi: 10.1016/j.jinf.2012.03.013. Epub 2012 Mar 21. PMID: 22445732.
  10. Paul M, Bishara J, Yahav D, Goldberg E, Neuberger A, Ghanem-Zoubi N, Dickstein Y, Nseir W, Dan M, Leibovici L. Trimethoprim-sulfamethoxazole versus vancomycin for severe infections caused by meticillin resistant Staphylococcus aureus: randomised controlled trial. BMJ. 2015 May 14;350:h2219. doi: 10.1136/bmj.h2219. PMID: 25977146; PMCID: PMC4431679.
  11. Lasko MJ, Gethers ML, Tabor-Rennie JL, Nicolau DP, Kuti JL. In Vitro Time-Kill Studies of Trimethoprim/Sulfamethoxazole against Stenotrophomonas maltophilia versus Escherichia coli Using Cation-Adjusted Mueller-Hinton Broth and ISO-Sensitest Broth. Antimicrob Agents Chemother. 2022 Mar 15;66(3):e0216721. doi: 10.1128/aac.02167-21. Epub 2022 Jan 10. PMID: 35007135; PMCID: PMC8923228.
  12. Lasko MJ, Tabor-Rennie JL, Nicolau DP, Kuti JL. Trimethoprim/sulfamethoxazole pharmacodynamics against Stenotrophomonas maltophilia in the in vitro chemostat model. J Antimicrob Chemother. 2022 Oct 28;77(11):3187-3193. doi: 10.1093/jac/dkac304. PMID: 36101486.

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