Treat Foot Infections in Diabetes Based on Severity

This complimentary article from Prescriber's Letter is being provided to readers of Pharmacist's Letter, who may find its content relevant to their practice.

Questions are coming up about how to treat foot infections in patients with diabetes.

Create an individualized care plan that includes debridement...wound care...off-loading...and a vascular referral, if needed.

Choose empiric antibiotics based on likely pathogens, your local antibiogram, and patient-specific factors (allergies, severity, etc).

Mild. For infections with superficial inflammation, cover gram-positives with oral cephalexin or dicloxacillin.

But for patients given antibiotics within the last month, also cover gram-negatives with agents such as amoxicillin/clavulanate.

Add methicillin-resistant Staph aureus (MRSA) coverage in patients at risk...such as those with a history of MRSA infection or known colonization. For example, think of doxycycline or TMP/SMX.

Don't empirically cover for Pseudomonas unless there are additional risk factors...such as frequent foot exposure to water (hot tub, lake, pool, etc).

Moderate. For wounds that are deeper or with erythema over 2 cm...withOUT systemic signs (fever, tachycardia, etc)...ensure gram-positive and gram-negative coverage.

Start amoxicillin/clavulanate in most cases, especially if you suspect anaerobes...such as a wound with a foul odor or necrosis.

And if needed, add empiric coverage for MRSA.

Consider IV antibiotics for high-risk patients, such as those with severe peripheral artery disease or unable to adhere to oral meds.

Severe. For any patient with at least 2 systemic signs...or not responding to oral therapy...jump to IV antibiotics. Cover gram-positives, gram-negatives, and anaerobes (ampicillin/sulbactam, etc).

But consider a med such as piperacillin/tazobactam if Pseudomonas coverage is needed. And for those at risk for MRSA, add IV vancomycin.

Use our FAQ, Foot Infections in Patients With Diabetes, for more nuances...such as duration of therapy, when to switch to PO, and tips for prevention.

Key References

  • Diabetes Metab Res Rev 2020;36(Suppl 1):e3280
  • Clin Infect Dis 2012;54(12):e132-73
  • Cochrane Database Syst Rev 2015;(9):CD009061
  • Infect Dis Clin North Am 2021;35(1):183-97
  • J Vasc Surg 2016;63(Suppl 2):3S-21S
Pharmacist's Letter. September 2021, No. 370912



Get concise advice on drug therapy, plus unlimited access to CE

Pharmacist's Letter includes:

  • 12 issues every year, with brief articles about new meds and hot topics
  • 300+ CE courses, including the popular CE-in-the-Letter
  • Quick reference drug comparison charts
  • Access to the entire archive

Already a subscriber? Log in

Volume pricing available. Get a quote