Urinary tract infections can occur in the bladder, kidneys, ureters and the urethra says MedlinePlus from the National Institutes of Health. According to the National Kidney and Urologic Diseases Information Clearinghouse, infections are primarily caused by bacteria, mostly E. coli, and in some cases Chlamydia and Mycoplasma. Antibiotics are commonly used to treat urinary tract infections, with the specific type of antibiotic dependent on the type of bacteria causing the infection.
Fluoroquinolones
Fluoroquinolones are a class of drugs that are replacing trimethoprim-sulfamethoxazole as the most popular prescribed antibiotic for urinary tract infections from E. coli, according to the University of Maryland Medical Center. Fluoroquinolones include norfloxacin, ciprofloxacin, ofloxacin and trovafloxin. According to the Centers for Disease Control, fluoroquinolones reduce the ability for E. coli to grow. Scientists are concerned about development of resistance by E. coli, Chlamydia and Mycoplasma to fluoroquinolones.
Fluoroquinolones are taken orally once or twice daily, maintain activity for most of the day and have a low incidence of serious side effects. However, fluoroquinolones could cause birth defects if taken during pregnancy and should not be the first-line prescription for children.
Beta-Lactams
Beta-lactams are a class of antibiotics that include penicillins and cephalosporins used to treat urinary tract infections. These antibiotics kill the bacteria causing the infection. Penicillins, such as amoxicillin and a combination of amoxicillin and clavulanate, are effective in treating urinary tract infections caused by E. coli, P. mirabilis and E. faecalis and beta-lactamase producing strains of E. coli, Klebsiella spp. and Enterobacter spp. bacteria, respectively. However, penicillins are ineffective in up to 25 percent of people infected by E. coli. Cephalosporins such as cefuroxime, cephalexin, cefixime, loracarbef and cefadroxil are used as alternatives for urinary tract infections that do not respond to other antibiotics. Beta-lactams can cure a urinary tract infection with two days of treatment, but are often prescribed longer.
Tetracyclines
Tetracyclines are a class of antibiotics that include doxycycline and minocycline used to treat urinary tract infections caused by Chlamydia and Mycoplasma. According to research published in "Microbiology and Molecular Biology Reviews," tetracyclines exhibit their antibiotic activity by inhibiting bacterial protein synthesis. Treatment usually exceeds a few days and can cause skin reactions to sunlight, tooth discoloration and burning in the throat. Pregnant women and children should not take tetracyclines. The high rate of tetracycline-resistant bacteria limits the use of these drugs.
References
- National Kidney and Urologic Diseases Information Clearinghouse: Urinary Tract Infections in Adults
- University of Maryland Medical Center: Urinary Tract Infection Medications
- PubMed Central: Tetracycline Antibiotics--Mode of Action, Applications, Molecular Biology, and Epidemiology of Bacterial Resistance
- "Microbiology and Molecular Biology Reviews"; Tetracycline Antibiotics; Chopra, I. and M. Roberts; Jun 2001
- Ortho-McNeil Janssen Scientific Affairs: Doribax Prescribing Information
