trimethoprim, Trimpex (Discontinued Brand), Proloprim (Discontinued Brand), Primsol
Omudhome Ogbru, PharmD
Omudhome Ogbru, PharmD
Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.
Medical and Pharmacy Editor:
GENERIC NAME: trimethoprim
BRAND NAMES: Primsol
DISCONTINUED BRANDS: Trimpex, Proloprim
DRUG CLASS AND MECHANISM: Trimethoprim is a synthetic (man-made) antibiotic that interferes with the production of tetrahydrofolic acid, a chemical that is necessary in order for bacteria and human cells to produce proteins. Trimethoprim inhibits production of tetrahydrofolic acid by inhibiting the enzyme responsible for making tetrahydrofolic acid from dihydrofolic acid. Trimethoprim inhibits the bacterial enzyme more than the human enzyme. Therefore, trimethoprim has less effect on the production of tetrahydrofolic acid by humans. Because of the frequent development of resistance to trimethoprim, it is more effective when combined with another antibiotic, sulfamethoxazole (Azo-Gantanol), and is rarely used alone. Trimethoprim was first approved by the FDA in combination with sulfamethoxazole (for example, Bactrim, Septra) in 1973. It was approved as a stand-alone drug in 1980.
PRESCRIBED FOR: Trimethoprim is used for the treatment of uncomplicated urinary tract infections due to susceptible bacteria.
SIDE EFFECTS: The most common side effects associated with trimethoprim are gastrointestinal, such as:
Medically Reviewed by a Doctor on 1/28/2015
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