Formulations for trans-tympanic antibiotic delivery.

We have developed a drug delivery system for prolonged trans-tympanic antibiotic delivery from a single dose administration. Increased permeability to ciprofloxacin of the intact tympanic membrane (TM) was achieved by chemical permeation enhancers (CPEs--bupivacaine, limonene, sodium dodecyl sulfate); this was also seen by CPEs contained within a hydrogel (poloxamer 407) to maintain the formulation at the TM. The CPE-hydrogel formulation had minimal effects on auditory thresholds and tissue response in vivo. CPE-hydrogel formulations have potential for ototopical delivery of ciprofloxacin for the treatment of acute otitis media (AOM) and other middle ear diseases.