Cefazolin
Ancef
First-generation cephalosporin
β-lactam — inhibits bacterial cell wall PBPs.
Indications
- •Surgical prophylaxis (most common SCIP antibiotic)
- •Skin/soft tissue infections (gram-positive)
Dosing
| Context | Adult | Pediatric |
|---|---|---|
| Surgical prophylaxis | 2 g IV (3 g if > 120 kg) | 30 mg/kg IV |
| Re-dose interval | q4 h intraop OR after blood loss > 1.5 L | — |
Pharmacokinetics
Onset 5 min. Half-life 1.5–2 h. Renal excretion.
Side effects
- !Allergy: ~1% true cross-reactivity with penicillin (modern data)
- !Phlebitis with peripheral push
- !C. diff (any antibiotic exposure)
Contraindications
- ×Documented anaphylaxis to cephalosporins
Clinical pearls
- ★Modern PCN allergy with non-anaphylactic history → cefazolin generally safe.
- ★Give within 60 min of incision (vancomycin within 120 min — slow infusion).
- ★Re-dose for case > 4 h or significant blood loss.
Education only — confirm against current package inserts and institutional protocols. Doses assume normal organ function unless otherwise noted.