cefadroxil

Brand: Duricef

Prototype: cephalexin
Drug Class: first-generation cephalosporin
Drug Family: antibiotic
Subclass: oral first-generation cephalosporin
Organ Systems: infectious-disease

Mechanism of Action

Inhibits bacterial cell wall synthesis by binding PBPs; bactericidal. First-generation spectrum covers gram-positive cocci and some gram-negative organisms.

penicillin-binding proteins (PBPs)

Indications

  • skin and soft tissue infections
  • group A streptococcal pharyngitis
  • uncomplicated UTI

Contraindications

  • cephalosporin hypersensitivity
  • severe penicillin allergy (cross-reactivity ~1–2%)

Adverse Effects

Common

  • diarrhea
  • nausea
  • skin rash

Serious

  • anaphylaxis
  • C. difficile colitis
  • serum sickness-like reaction

Pharmacokinetics (ADME)

Absorption >90% oral bioavailability; food does not affect absorption
Distribution widely distributed; poor CSF penetration
Metabolism not significantly metabolized
Excretion renal (unchanged); dose reduction required in CKD
Half-life 1.5 hours
Onset rapid
Peak 1–2 hours
Duration 12–24 hours
Protein Binding 20%
Vd moderate

Drug Interactions

Drug / Agent Mechanism Severity
probenecid blocks renal tubular secretion, increasing cefadroxil levels moderate
warfarin gut flora suppression reduces vitamin K; enhanced anticoagulation moderate

Nursing Considerations

  1. May be taken with or without food; advise patients that GI upset is reduced by taking with meals.
  2. Assess for penicillin or cephalosporin allergy before administration; cross-reactivity is low (~1–2%) but possible.
  3. Monitor renal function; dose reduction is required when CrCl falls below 50 mL/min.
  4. Instruct patient to complete the full course even if symptoms improve.

Clinical Pearls

  • Cefadroxil offers the convenience of once- or twice-daily dosing compared to cephalexin's four-times-daily regimen.
  • It is an acceptable alternative to penicillin for streptococcal pharyngitis in non-anaphylactic penicillin-allergic patients.

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.