Melkersson–Rosenthal syndrome (MRS) is a rare disorder of unknown etiology. It is characterized by the triad of macrocheilitis, peripheral facial palsy, and lingua plicata.

A 48-year-old nonobese man with a diagnosis of MRS and marked macroglossia was evaluated because of clinically suspected obstructive sleep apnea (OSA). Established causes of OSA such as anatomic abnormalities of the upper airways or the facial skeleton were not present in this patient. Furthermore, hypothyroidism and acromegaly were excluded as underlying diseases. Polysomnography revealed moderate-to-severe OSA. As the swelling of the tongue had been unresponsive to immunosuppressive pharmacotherapy and surgery did not seem to be a reasonable therapeutic option, the patient was finally treated by continuous positive airway pressure therapy.

To the best of our knowledge, this is the first report of OSA occurring in a patient with MRS.