Cefixime

# Cefixime ## Overview - **Classification**: Third-generation cephalosporin antibiotic. - **Mechanism**: Inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), leading to bacterial cell lysis. ## Primary Indications 1. **Acute Otitis Media (AOM)** - Bacterial infection of the middle ear. 2. **Pharyngitis/Tonsillitis** - Due to *Streptococcus pyogenes* (Group A Strep). 3. **Acute Exacerbations of Chronic Bronchitis (AECB)** - Bacterial exacerbations. 4. **Uncomplicated Urinary Tract Infections (UTI)** - Caused by susceptible organisms. 5. **Uncomplicated Gonorrhea** - Cervical, urethral, rectal infections. ## Adult Dosing ### Standard Dosing **Acute Otitis Media, Pharyngitis/Tonsillitis, AECB, Uncomplicated UTI** - **Dose**: **400 mg** - **Frequency**: Once daily OR **200 mg** every 12 hours - **Route**: Oral - **Duration**: 7-14 days (varies by indication); 10 days for Strep Pharyngitis. **Uncomplicated Gonorrhea** - **Dose**: **800 mg** - **Frequency**: Single dose - **Route**: Oral ### Dose Adjustments - **Renal Impairment**: - CrCl 21-60 mL/min: **300 mg** orally once daily. - CrCl < 20 mL/min (including dialysis): **200 mg** orally once daily. - **Hepatic Impairment**: No specific dose adjustment generally needed. - **Elderly Patients**: No specific dose adjustment solely based on age; assess renal function. ## Pediatric Dosing ### Neonates (0-28 days) - **Dose**: Not routinely recommended due to limited safety data. - **Special Notes**: Consult infectious disease specialist if considering use. ### Infants (1-12 months) - **Dose**: **8 mg/kg/day** - **Frequency**: Once daily OR divided every 12 hours - **Maximum**: **400 mg/day** - **Special Notes**: Oral suspension preferred. ### Children (1-12 years) - **Dose**: **8 mg/kg/day** - **Frequency**: Once daily OR divided every 12 hours - **Maximum**: **400 mg/day** (unless treating gonorrhea where adult dose may apply based on weight/pubertal stage) - **Special Notes**: Oral suspension for younger children, chewable tablets also available. ### Adolescents (13-18 years) - **Dose**: Adult dosing applies. - **Maximum**: **400 mg/day** (or **800 mg** single dose for gonorrhea). ## Safety Information ### Contraindications - **Absolute**: Hypersensitivity to cefixime or other cephalosporin antibiotics. - **Absolute**: History of severe hypersensitivity (e.g., anaphylaxis) to penicillins. ### Common Adverse Effects - **Very Common (>10%)**: Diarrhea, Nausea, Abdominal pain. - **Common (1-10%)**: Headache, Dizziness, Flatulence, Dyspepsia, Rash. - **Serious but Rare**: *Clostridioides difficile*-associated diarrhea (CDAD), Stevens-Johnson Syndrome (SJS), Toxic Epidermal Necrolysis (TEN), Anaphylaxis, Hemolytic anemia, Renal dysfunction. ### Key Drug Interactions - **Oral Anticoagulants (e.g., Warfarin)**: May increase INR and bleeding risk. Monitor INR closely. - **Probenecid**: May increase cefixime plasma concentrations by decreasing renal excretion. - **Carbamazepine**: May increase carbamazepine plasma levels. Monitor carbamazepine levels. ## Monitoring & Follow-up - **Before Treatment**: Assess allergies, renal function (CrCl). - **During Treatment**: Monitor for signs of allergic reaction (rash, dyspnea), severe diarrhea, or superinfection. - **Clinical Signs**: Worsening symptoms of infection, new onset fever, severe watery diarrhea. ## Clinical Pearls - 💡 Administer with or without food; food may help reduce GI upset. - 💡 Complete the full course of treatment, even if symptoms improve, to prevent resistance. - 💡 Oral suspension must be shaken well before each use. Store reconstituted suspension at room temperature or in refrigerator. - 💡 **Gonorrhea**: For uncomplicated gonorrhea, CDC recommends Ceftriaxone **500 mg** IM as preferred. Cefixime **800 mg** orally is an alternative if IM Ceftriaxone is not feasible. Co-treatment for *Chlamydia trachomatis* is often indicated. > **⚠️ Important**: This information is for educational purposes only. Always consult current prescribing information, local guidelines, and clinical judgment before prescribing.