Which antibiotic is most commonly used for urinary tract infections (UTIs)?

Trimethoprim is commonly used for urinary tract infections (UTIs) due to its effectiveness against the bacteria that frequently cause these infections, such as Escherichia coli. It works by inhibiting bacterial folic acid synthesis, which is essential for bacterial growth and reproduction. This mechanism makes it particularly effective in the urinary tract, where bacterial infection is prevalent.

The choice of Trimethoprim as a first-line treatment is also influenced by factors such as its favorable pharmacokinetics, allowing for good renal excretion and adequate concentrations in the urine. Additionally, it is typically well-tolerated with a relatively low incidence of side effects, making it a preferred choice among healthcare providers for non-complicated UTIs.

In contrast, while other antibiotics on the list may also be used for UTIs, they are generally not the first choice. For example, Ciprofloxacin is a fluoroquinolone that is effective for a broader range of infections but may be reserved for cases where first-line therapies fail or in complicated infections to limit the development of resistance. Amoxicillin has some effectiveness against uncomplicated UTIs but is less commonly used now due to rising resistance rates. Azithromycin is primarily used for respiratory infections and certain sexually transmitted infections,