Otic administration of amphotericin B 0.25% in sterile water

Abstract

Objective: To report otic administration of parenteral amphotericin B 0.25% in sterile water.

Case summary: A 44-year-old HIV+ man was diagnosed with otitis externa. The patient's past medical history was remarkable for positive Coccidioides immitis serology for more than five months, essential hypertension, and Barrett's esophagitis. Culture results from an ear swab revealed 4+ Aspergillus fumigatus and 3+ Staphylococcus, coagulase negative. Antiinfective therapy for the otitis externa included oral and topical antibacterial and antifungal medications. Amphotericin B 0.25% in sterile water was prepared by the pharmacy for topical otic administration. The otic amphotericin B was dispensed with instructions to refrigerate and assigned a one-week expiration date. The prescription called for instillation of 1-2 drops in each ear three times a day. The patient's signs and symptoms of otitis externa resolved during several weeks of antiinfective therapy. Topical administration of amphotericin B 0.25% in sterile water was not associated with any local adverse effects in this patient.

Discussion: The rationale for use of the parenteral amphotericin B formulation to prepare an otic dosage form, and the rationale for the specific concentration and expiration date chosen are discussed.

Conclusions: This patient tolerated topical otic administration of amphotericin B 0.25% in sterile water when administered three times daily.