What can help with sleep onset terrors?
QA patient has suffered lifelong vivid and terrifying experiences while falling asleep (voices, visions, feelings of altered body shape and sleepwalking). I've heard this described as Alice in Wonderland syndrome. What might be helpful?
ATerrifying hypnagogic hallucinations occur at sleep onset and are just like nightmares at later stages of sleep. Typically, dreams start with less dramatic experiences but progress to intense and often threatening hallucinations, with the patient waking in a state of anxiety after a period of major body movements, screaming and moaning.
Unlike sleep terrors, the content can be recalled in vivid detail. Occasionally they may be aware of both the real environment and the dream.
Hypnagogic hallucinations are a feature of narcolepsy, so this diagnosis must be considered, but they can also present alone, especially after sleep deprivation, stress or drugs acting on the central nervous system. Sleep onset insomnia can occur as a result of the fear induced by these experiences which occur in sleep onset REM periods.
Differential diagnoses (in addition to narcolepsy) include normal reverie on going to sleep (not frightening), 'exploding head syndrome' (sudden loud noises or flashes on going to sleep), sleep terrors (usually seen about 90 minutes after sleep onset and associated with marked autonomic activation but little recall) and, rarely, epileptic seizures at sleep onset.
Treatment consists of sleep hygiene, avoiding stimulants and sleep deprivation. Clomipramine 25-75mg one hour before retiring or an SSRI is often effective. Desensitisation and a psychotherapeutic approach may also be needed.
Dr Jonathan Bird is consultant neuropsychiatrist, the Burden
Centre for Neuropsychiatry,
Frenchay Hospital, Bristol