Sleepwalking Disorder

Sleepwalking (somnambulism) is repeated episodes of complex behaviours arising from non-REM slow wave sleep, with impaired responsiveness and amnesia.

• Prevalence 17% in children (peak at 8 to 12 years), 2 to 4% in adults.
• Familial (HLA, genetics); triggers: sleep deprivation, fever, stress, alcohol, sedative hypnotics (zolpidem), sleep apnoea, restless legs, nocturnal seizures, pain.
• Episodes in first third of night.
• Complications: injuries, violence, driving, sexsomnia.

• Rising from bed, wandering, eating, talking, glassy stare, difficult to awaken, no memory of event, lasting 1 to 30 minutes.
• Associated sleep talking, sleep terrors.
• Adult onset warrants investigation.

• Clinical, with collateral history and home video.
• Video polysomnography for injurious, frequent or adult onset episodes: shows arousals from N3 sleep; exclude sleep apnoea, periodic limb movement, REM behaviour disorder, nocturnal frontal lobe epilepsy (extended EEG).
• Review drugs (zolpidem, lithium, antipsychotics).
• Screen mood and anxiety.

• Safety measures: lock doors and windows, remove hazards, avoid sleeping upstairs, door alarms.
• Sleep hygiene: regular schedule, adequate sleep, avoid alcohol, caffeine and triggers; treat sleep apnoea (CPAP), restless legs.
• Children: scheduled awakenings 15 to 30 minutes before the typical episode time for 4 to 6 weeks; most resolve.
• Medication for dangerous or frequent episodes: clonazepam 0.5 to 1 mg at night, or low dose melatonin, trazodone 25 to 100 mg, paroxetine 20 mg.
• Stop precipitating drugs; hypnosis, CBT, relaxation.
• Counselling regarding legal responsibility and driving.