Overview
Cefixime is a third-generation cephalosporin antibiotic with broad-spectrum activity against Gram-negative bacteria. It is commonly used to treat various bacterial infections including otitis media, pharyngitis, urinary tract infections, and uncomplicated gonorrhea. The drug works by inhibiting bacterial cell wall synthesis, leading to bacterial cell death.
Mechanism of Action
Cefixime is a bactericidal antibiotic that inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs). This interference prevents the final transpeptidation step of peptidoglycan synthesis in bacterial cell walls, leading to cell lysis and death.
Indications
- Acute otitis media caused by Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis
- Pharyngitis and tonsillitis caused by Streptococcus pyogenes
- Acute bronchitis and acute exacerbations of chronic bronchitis caused by Streptococcus pneumoniae and Haemophilus influenzae
- Uncomplicated urinary tract infections caused by Escherichia coli and Proteus mirabilis
- Uncomplicated gonorrhea (cervical/urethral) caused by Neisseria gonorrhoeae
Common Doses
- 400 mg capsules
- 100 mg/5 mL oral suspension
- 200 mg/5 mL oral suspension
Dosage
Typical adult dosage is 400 mg once daily. For otitis media, the recommended pediatric dosage is 8 mg/kg once daily. Dosage adjustments may be necessary for renal impairment. The drug may be taken with or without food.
Contraindications
- Known hypersensitivity to cefixime
- Known allergy to cephalosporin class antibiotics
Side Effects
- Diarrhea (most common)
- Nausea
- Abdominal pain
- Dyspepsia
- Flatulence
- Headache
- Vaginitis
- Rash
- Elevated liver enzymes
- Pseudomembranous colitis
Interactions
- Probenecid may increase and prolong cefixime blood levels
- May reduce efficacy of oral contraceptives - recommend alternative contraception
- May cause false-positive Coombs' test
- Concurrent use with potent diuretics may increase risk of nephrotoxicity
Counseling Points
- Complete the full course of therapy even if symptoms improve
- May be taken with or without food
- Report severe diarrhea, abdominal pain, or blood/mucus in stool immediately
- Inform healthcare provider of any allergic reactions to penicillin or cephalosporins
- Use alternative contraception if taking oral contraceptives during therapy