Can Cefepime Be Given Intramuscularly?
Yes, cefepime can be administered intramuscularly and is FDA-approved for IM administration with specific reconstitution instructions. 1
FDA-Approved IM Administration
The FDA label explicitly provides detailed preparation instructions for intramuscular cefepime administration 1:
- For 1 gram IM dose: Reconstitute with 2.4 mL of diluent to achieve a concentration of 280 mg/mL, yielding 3.6 mL total volume 1
- Approved diluents for IM preparation: Sterile Water for Injection, 0.9% Sodium Chloride, 5% Dextrose Injection, 0.5% or 1% Lidocaine Hydrochloride, or Sterile Bacteriostatic Water for Injection with Parabens or Benzyl Alcohol 1
- Stability after reconstitution: IM cefepime remains stable for 24 hours at room temperature (20°C to 25°C) or 7 days refrigerated (2°C to 8°C) 1
Clinical Context for IM Use
IM cefepime should be considered primarily when vascular access is limited or unavailable in emergency situations. 2
The Surviving Sepsis Campaign guidelines specifically mention IM cefepime as an option when timely establishment of vascular access is not possible 2. The American Academy of Pediatrics recognizes IM cefepime for managing various infections including urinary tract infections and bacteremia when no focus is identified 2.
Pharmacokinetic Profile
IM administration provides reliable drug delivery with excellent bioavailability 3:
- Bioavailability: Approximately 82-100% after IM injection 4, 3
- Peak concentration timing: Achieved at 1.0-1.6 hours post-injection 3
- Elimination half-life: Approximately 1.8-2 hours, slightly prolonged compared to IV due to absorption kinetics 4, 3
- Tolerability: Well tolerated with none to mild pain and minimal discomfort at injection site 3
Pediatric Considerations
IM cefepime is appropriate for pediatric patients aged 2 months and older 4:
- Pharmacokinetic data support a single dosing strategy of 50 mg/kg every 12 hours for patients ≥2 months of age 4
- Bioavailability in children averages 82% (range 61-124%) 4
- No significant differences in disposition characteristics between age groups beyond 6 months 4
Important Clinical Caveats
Always prioritize IV administration when vascular access is readily available, as this remains the preferred route for serious infections 2. The IM route should be reserved for situations where IV access is genuinely problematic or delayed.
Patients with renal impairment require dosage adjustment regardless of administration route to prevent neurotoxicity (encephalopathy, seizures, myoclonus) 1. The same dosing adjustments based on creatinine clearance apply to both IV and IM routes 1.