Simultaneous quantification of trimethoprim metabolites in pediatric plasma.

The dual agent antibiotic, trimethoprim/sulfamethoxazole (TMP-SMX), has been prescribed to treat or prevent infections for over 50 years. However, there are no published validated analytical methods for the measurement of TMP metabolites in humans. We developed methodology enabling reliable quantification of TMP and 5 metabolites in human plasma.

Screening Trimethoprim Primary Metabolites for Covalent Binding to Albumin.

Modification of endogenous proteins by drugs and drug metabolites are thought to be a cause of idiosyncratic adverse drug reactions (IADRs). Trimethoprim (TMP) is a commonly prescribed antibiotic that has been implicated in IADRs; however, there is no known mechanism by which this drug or its metabolites modify proteins. This study describes the results of screening trimethoprim and its primary metabolites for the ability to covalently modify human serum albumin (HSA).