When is sleep study recommended for insomnia?

Insomnia means difficulty falling asleep, staying asleep or waking too early despite having an opportunity to sleep. A sleep study records signals such as breathing, oxygen levels, heart rate, brain activity and movement while you sleep. It is more useful when there is loud snoring, witnessed pauses in breathing, gasping, restless or jerking legs, dream-enactment behaviour, marked daytime sleepiness or symptoms that do not fit straightforward insomnia. Many insomnia assessments begin with history, a sleep diary and review of medicines, routines and mood.

Tell your clinician about bedtime, awakenings, snoring, breathing pauses, leg sensations, naps and daytime alertness. Record sleep and wake times in a diary, and list medicines, caffeine, alcohol and substances that may affect sleep. Ask whether home monitoring or an overnight centre-based test is more suitable. Learn about [Sleep Study](/treatments/diagnostics-and-screening/sleep-study/) and [Insomnia](/conditions/insomnia/) before the appointment.

Seek prompt medical advice if sleepiness causes near-misses while driving or operating equipment, if breathing repeatedly stops at night, or if you wake choking or severely short of breath. Urgent help is needed for chest pain, severe breathing difficulty or immediate risk of harm. Do not drive when you cannot stay alert.

Ask what features make a sleep study useful, which type of test is appropriate, whether medicines should be changed before testing, and what treatment could follow the result.