Central sleep apnoea due to a medication or substance

**Definition:** Central sleep apnoea due to a medication is characterised by a pattern of recurring, predominantly central sleep apnoea or hypopnoea (more than five per hour) that is attributable to a medication or substance, most commonly long-acting opioids (e.g. methadone, long-acting morphine or oxycodone, fentanyl patches). The disturbance is sufficiently severe to cause symptoms such as daytime sleepiness, disturbed sleep, awakening with dyspnoea, or snoring. Obstructive apnoeas and hypoventilation may be present, but central sleep apnoea is the predominant finding.

Note: A definitive diagnosis requires objective evidence based on polysomnography in the context of medication or substance use that is judged to be causing the symptoms.