Does cefepime affect blood sugar levels?

Cefepime Does Not Directly Affect Blood Sugar Levels

Cefepime is not associated with causing hyperglycemia or hypoglycemia and does not directly affect blood glucose metabolism. The FDA-approved labeling for cefepime does not list dysglycemia as an adverse effect, and the drug's mechanism of action as a fourth-generation cephalosporin antibiotic does not involve glucose homeostasis 1.

Evidence Base

Direct Effects on Glucose

• Cefepime's pharmacologic profile shows no interaction with insulin secretion, glucose absorption, or hepatic glucose metabolism 2, 3
• The drug is primarily excreted unchanged by renal mechanisms with a half-life of approximately 2 hours, without metabolic pathways that would affect glucose regulation 4
• Clinical trials and pharmacokinetic studies have not identified dysglycemia as an adverse effect of cefepime 2, 4

Comparative Data with Other Antibiotics

• A retrospective study of 17,108 hospitalized patients compared dysglycemia rates across antibiotics and found ceftriaxone (a third-generation cephalosporin) had a dysglycemia rate of only 0.18%, significantly lower than fluoroquinolones 5
• This study provides indirect evidence that cephalosporins as a class, including cefepime, have minimal impact on blood glucose 5
• The dysglycemia events observed with ceftriaxone were primarily in patients with pre-existing diabetes or those receiving concomitant sulfonylureas 5

Important Clinical Caveats

False Laboratory Results

• Cefepime can cause false-positive urine glucose tests when using certain methods (e.g., Clinitest tablets), but this is a laboratory artifact, not an actual change in blood glucose 1
• This does not reflect true hyperglycemia and should not be confused with actual dysglycemia 1

Indirect Effects in Critically Ill Patients

• While cefepime itself does not affect blood sugar, critically ill patients receiving cefepime may experience glucose fluctuations due to:
  • Underlying infection and inflammatory response
  • Concurrent medications (corticosteroids, vasopressors)
  • Nutritional status changes
  • Stress hyperglycemia from sepsis 6

Neurotoxicity Considerations

• Cefepime's most significant adverse effect is neurotoxicity (encephalopathy, seizures, myoclonus), particularly in patients with renal impairment who do not receive appropriate dose adjustments 1, 7
• This neurotoxicity is unrelated to glucose metabolism but is critical to monitor, especially in patients with estimated glomerular filtration rate below 60 mL/min 1, 7
• Symptoms are typically reversible after discontinuation or hemodialysis 1, 7

Clinical Monitoring Recommendations

• Do not attribute blood glucose changes to cefepime unless all other causes have been excluded 5
• Continue standard glucose monitoring protocols based on the patient's underlying diabetes status and critical illness, not because of cefepime use 6
• If using urine glucose testing (uncommon in modern practice), be aware of potential false-positive results and confirm with serum glucose measurements 1
• Focus monitoring efforts on cefepime's actual adverse effects: neurotoxicity in renal impairment, hypersensitivity reactions, and Clostridioides difficile infection 1