Urinary tract infection (UTI) can happen anywhere along the urinary tract - the kidney (pyelonephritis), the ureters, the bladder (cystitis), or the urethra (urethritis). Left untreated, it can lead to acute or chronic pyelonephritis which can permanently damage the kidneys.
Women are more prone to UTIs because their urethras are shorter and closer to the anus. UTIs are most common in sexually active women, in diabetics and people with sickle-cell disease or anatomical malformations of the urinary tract.
Commonly Prescribed Drugs
Antibiotics are the first line of treatment for most UTIs. The treatment regimen will depend on the patient's health condition and the bacteria found in urine tests.
- Sulfonamides (sulfadiazine, sulfamethoxazole, sulfisoxazole). They kill the bacterium by interfering with para-aminobenzoic acid (PABA), the enzyme that helps form folic acid a chemical necessary for bacterial growth.
- Drug Interaction: Sulfonamides should not be given with anticoagulants, barbiturate anesthetics, hydantoins, sulfonylureas, diuretics and salicylates.
- Trimethoprim inhibits bacterial growth by blocking the production of dihydrofolate reductase, an enzyme that completes the synthesis of proteins and nucleic acids needed by bacterial cells to multiply. Phenytoin's pharmacologic effects may be increased with co-administration of trimethoprim.
- Quinolones (ciprofloxacin, gatifloxacin, norfloxacin, levofloxacin, ofloxacin, pefloxacin) works by inhibiting the enzymes (DNA gyrase, topo-isomerase IV) responsible for bacterial DNA replication.
- Penicillins (amoxicillin, ampicillin, amoxicillin clavulanic acid, cloxacillin, sultamicillin) interferes with bacterial cell wall synthesis.
- Drug Interaction: Penicillins should not be given with oral contraceptives, heparin, allopurinol, erythromycin, tetracyclines, cyclosporine and probenecid.
- Nitrofurantoin interferes with bacterial cell wall formation and bacterial duplication.
- Drug Interaction: It should not be given with anticholinergic drugs, magnesium salts and probenecid.
- Other Drugs:
- Sulfonamide Combinations: Trimethoprim and sulfamethoxazole (Cotrimoxazole)
- Aminoglycosides: Amikacin, Gentamicin, Netilmicin.
- Carbapenems: Ertapenem, Meropenem, Imipenem.
- 1st Generation Cephalosporins: Cefalexin, Cefradine, Cefadroxyl, Cefazolin.
- 2nd Generation Cephalosporins: Cefaclor, Cefoxitin, Cefu-roxime.
- 3rd Generation Cephalosporins: Cefpodoxime, Cefoperazone, Ceftazidime, Ceftriaxone, Ceftizoxime.
- 4th Generation Cephalosporins: Cefepime.
- Chloramphenicols: Chloramphenicol.
- Macrolides: Erythromycin. Monocyclic Beta-lactam
- Antibiotic: Aztreonam
Side effects: Rashes, headache, convulsions, drowsiness, nausea, vomiting, GI disturbances, hypersensitivity and renal stones (crystalluria), leukopenia, neutropenia and megaloblastic anemia.