cefaclor
Brand: Ceclor
Prototype: cefuroxime
Drug Class: second-generation cephalosporin
Drug Family: antibiotic
Subclass: oral second-generation cephalosporin
Organ Systems: infectious-disease
Mechanism of Action
Inhibits bacterial cell wall synthesis by binding PBPs; improved gram-negative coverage over first-generation cephalosporins while retaining gram-positive activity.
penicillin-binding proteins (PBPs)
Indications
- otitis media
- sinusitis
- community-acquired pneumonia
- skin and soft tissue infections
- UTI
Contraindications
- cephalosporin hypersensitivity
Adverse Effects
Common
- diarrhea
- nausea
- skin rash
Serious
- serum sickness-like reaction (more common with cefaclor than other cephalosporins)
- anaphylaxis
- C. difficile colitis
Pharmacokinetics (ADME)
| Absorption | ~90% oral bioavailability; food slows but does not reduce absorption |
| Distribution | widely distributed; poor CSF penetration |
| Metabolism | partial hepatic |
| Excretion | renal (~60–85% unchanged) |
| Half-life | 0.5–1 hour |
| Onset | rapid |
| Peak | 0.5–1 hour |
| Duration | 8 hours |
| Protein Binding | 25% |
| Vd | moderate |
Drug Interactions
| Drug / Agent | Mechanism | Severity |
|---|---|---|
| probenecid | reduces renal excretion of cefaclor | minor |
| warfarin | may enhance anticoagulation via gut flora suppression | moderate |
Nursing Considerations
- May be taken with or without food; advise food if GI upset occurs.
- Counsel patients about the risk of serum sickness-like reaction (rash, arthralgia, low-grade fever) more common with cefaclor than other cephalosporins; report these symptoms.
- Assess for cephalosporin or penicillin allergy history before administration.
- Complete the full course; instruct patient not to share medication.
Clinical Pearls
- Cefaclor has a higher rate of serum sickness-like reactions than other cephalosporins, an important counseling point.
- For otitis media in children, cefaclor offers improved coverage of H. influenzae compared to first-generation agents.
Safety Profile
Pregnancy generally-safe
Lactation use-with-caution
Renal Adjustment Required
Hepatic Adjustment Not required
TDM Not required
Concordance Terms
Cross-referenced clinical concepts — click any term to see all content where it appears.