Reversible hearing loss in temporal association with chemoprophylactic mefloquine use.

A 67 year old Caucasian lady received pre-travel immunizations against tetanus, diphtheria, typhoid fever, hepatitis A, and mefloquine chemoprophylaxis. Left sided hearing loss consequent upon tympanic rupture was present since childhood; she was otherwise in good health and without history of recent upper respiratory tract infection. After 1 dose of mefloquine right sided tinnitus and hearing loss developed; audiometry revealed mixed left sided loss and right sided sensorineural loss (-90db at 1kHz; -70dB at 4kHz). Prednisone, aspirin and omeprazole were prescribed; mefloquine chemoprophylaxis was discontinued. On day 9 of her hearing loss the tinnitus suddenly disappeared, and right sided hearing improved. Audiometry on day 93 revealed normal right sided hearing (-10dB at 1kHz; -10dB at 4kHz). Causality remains undetermined, but it may be prudent to avoid mefloquine chemoprophylaxis in individuals with known hearing impairment.