Obstructive sleep apnoea (OSA) is characterized by abnormal breathing during sleep, and occurs when the upper airway is obstructed but respiratory effort continues. Causes of OSA include obesity, overindulgence in alcohol, and the use of sedatives. The patient complains of unrefreshed sleep, morning headaches and drowsiness, sometimes leading to depression and intellectual impairment. The treatment of choice is weight loss; however, the patient may also require mechanical nocturnal support to prevent the upper airway collapsing and causing OSA. A simple and effective non-surgical treatment for OSA is nasal continuous positive airway pressure.