Also found in: Thesaurus, Medical, Acronyms, Encyclopedia, Wikipedia.


An antibiotic drug, C14H18N4O3, used primarily to treat or prevent urinary tract infections, often in combination with sulfamethoxazole.

[tri- + meth- + o(xy)- + p(y)rim(idine).]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Pharmacology) an antibiotic often prescribed to be taken with a sulphonamide, esp to treat urinary infections
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(traɪˈmɛθ ə prɪm)

a synthetic crystalline compound, C11H18N4O3, usu. combined with a sulfonamide as an antibiotic preparation in the treatment of urinary tract infections and pneumocystis pneumonia.
[1960–65; trimetho(xyphenyl) + p(y)rim(idinediamine), components of its chemical name]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
The researchers found that 85.7 percent of UTIs had same-day antibiotic prescribing; 56.8 percent were treated with trimethoprim and 25.0 percent underwent urine sampling.
In our case, the sequence of events was probably development of prerenal failure due to the natriuretic effect of trimethoprim, resulting in further accumulation of trimethoprim and increasing the risk of hyperkalaemia.
Trimethoprim Sulfamethoxazole has significant potential to cause congenital defects in developing embryo.
sulphamethoxazole/ trimethoprim (SXT), which was introduced in year 1930 (Tadesse et al.
Trimethoprim is antibiotic agent with large spectrum commonly used in chemotherapy for the treatment of enteric, respiratory and urinary tract infections [11].
MICs to trimethoprim were determined by the agar dilution method described by the Clinical Laboratory Standards Institute (2006).
We therefore tested the hypothesis that trimethoprim use during the months prior to pregnancy increases the risk of congenital malformations.
Major Finding: Between 1998 and 2009, prescriptions for the first-line urinary anti-infectives trimethoprim/sulfamethoxazole, trimethoprim, fosfomycin, and nitrofurantoin for uncomplicated cystitis in women remained constant (P= .10); yet prescriptions for quinolones grew by 10% and prescriptions for cephalosporins grew by 3% (P less than .01 and P= .02, respectively).
Treatment of traveller's diarrhea with trimethoprim-sulphamethoxazole and with trimethoprim alone.
Bactrim is dosed on the trimethoprim portion of the combo.
They were randomized to receive either 500 mg of Cran-Max or 100 mg of trimethoprim for six months.