Is mupirocin (antibiotic ointment) appropriate for treating an ingrown toenail?

Mupirocin for Ingrown Toenail Treatment

Mupirocin is not recommended as the primary treatment for ingrown toenails as it does not address the underlying mechanical issue causing the condition. 1, 2

Understanding Ingrown Toenails

• Ingrown toenails (onychocryptosis) occur when the edge of the nail plate grows into the surrounding soft tissue, causing pain, inflammation, and potentially infection 1
• They account for approximately 20% of foot problems in primary care, most commonly affecting the great toe 1
• Contributing factors include improper nail trimming, trauma, genetic predisposition, hyperhidrosis, and poor foot hygiene 2

Appropriate Management Approach

Primary Treatment Options

• The cornerstone of ingrown toenail management is mechanical correction of the nail-fold relationship, not antimicrobial therapy 1, 2
• For mild to moderate cases, nonsurgical approaches include:
  • Correcting improper footwear 1
  • Soaking the affected toe in warm, soapy water 2
  • Placing cotton wisps or dental floss under the ingrown nail edge 2
  • Gutter splinting to separate the nail from the lateral fold 1

Surgical Approaches

• For moderate to severe cases, surgical intervention is superior to nonsurgical approaches for preventing recurrence 1
• Partial nail avulsion with phenolization is more effective than surgical excision alone in preventing symptomatic recurrence 2, 3
• Randomized clinical trials show that phenol application gives significantly better results than matrix excision regarding recurrence rates 3

Role of Antimicrobials

• Topical antibiotics like mupirocin are not indicated as primary therapy for uncomplicated ingrown toenails 1, 2
• Local antibiotics have not been shown to reduce signs of infection or recurrence rates in clinical trials 3
• For cases with secondary bacterial infection:
  • Bacterial cultures should be considered before starting antibiotics, especially in severe cases 4
  • Augmentin (amoxicillin-clavulanate) may be recommended for infected paronychia at 500 mg/125 mg every 12 hours 4

When Mupirocin Might Be Considered

• Mupirocin may be appropriate only in specific limited scenarios:
  • For mild cases of neonatal pustulosis with localized disease 5
  • For superficial secondary bacterial infections after addressing the mechanical issue 6
  • When there is evidence of localized staphylococcal or streptococcal infection 6

Important Considerations and Pitfalls

• Treating only the infection without addressing the mechanical problem will lead to recurrence 1, 2
• Up to 25% of paronychia cases may have secondary fungal infections requiring antifungal therapy 4
• Overuse of topical antibiotics like mupirocin can contribute to antimicrobial resistance 6
• Phenolization does not increase infection risk compared to matrix excision 3