Is mupirocin safe to use on penile infections?

Safety of Mupirocin for Penile Infections

Mupirocin 2% ointment can be safely used for localized penile infections, particularly those caused by Staphylococcus aureus, but should not be applied to mucosal surfaces of the penis due to potential irritation and absorption concerns.

Indications and Safety Profile

• Mupirocin is indicated for topical treatment of impetigo and other localized skin infections caused by susceptible strains of Staphylococcus aureus and Streptococcus pyogenes 1, 2.
• It can be safely applied to the skin of the penis for treating superficial skin infections, but caution should be exercised when applying to mucosal surfaces 2.
• The FDA label specifically notes that "mupirocin ointment is not formulated for use on mucosal surfaces" 2.

Considerations for Penile Application

• When treating penile skin infections:

  • Apply only to the keratinized skin of the penis (shaft, pubic area) 2.
  • Avoid application to the glans penis if uncircumcised, as this is mucosal tissue 2.
  • Do not apply to the urethral meatus or inside the urethra 2.

• Potential concerns with mucosal application include:

  • Stinging and drying (reported with intranasal use) 2.
  • Possible increased absorption of the polyethylene glycol vehicle through mucosal surfaces 2.
  • Risk of irritation to sensitive tissues 2.

Efficacy for Skin Infections

• Mupirocin has excellent activity against Staphylococcus aureus (including MRSA) and Streptococcus species, which are common causes of skin infections 1, 3.
• Clinical trials have shown 73.7% cure rates and 22.5% marked improvement in patients with various skin infections treated with mupirocin 3.
• It has been successfully used for treatment of impetigo and secondarily infected skin lesions 3, 4.

Special Case: Zoon's Balanitis

• There is a case report of successful treatment of Zoon's balanitis (balanitis circumscripta plasmacellularis) with topical mupirocin 2% ointment 5.
• This suggests that in specific cases, mupirocin may be used on penile tissue under medical supervision 5.

Precautions and Monitoring

• Treatment should be discontinued if sensitivity reactions or chemical irritation occur 2.
• Prolonged use may result in overgrowth of nonsusceptible organisms, including fungi 2.
• In patients with moderate to severe renal impairment, caution should be exercised due to potential absorption of polyethylene glycol from the ointment base 2.
• Monitor for local side effects such as burning, itching, and reddening, which occur in approximately 2.9% of patients 3.

Alternative Approaches for Penile Infections

• For infections involving mucosal surfaces of the penis, alternative antimicrobial agents formulated for mucosal use may be more appropriate 1.
• For skin abscesses, incision and drainage along with appropriate systemic antibiotics based on culture results is recommended 1.
• For MRSA infections, treatment options include trimethoprim-sulfamethoxazole, doxycycline, or clindamycin for susceptible isolates 1.

Conclusion

When treating penile infections, mupirocin 2% ointment can be safely used on the keratinized skin portions but should be avoided on mucosal surfaces. Careful patient monitoring for irritation or sensitivity reactions is recommended, and treatment should be discontinued if such reactions occur 2.