To diagnose the cause of insomnia, your doctor will perform a complete physical examination and take a medical history.
This will include a history of your lifelong sleep patterns, previous experiences of insomnia, and recent life stresses. Be sure to tell your doctor about any prescription or non-prescription medication you might be taking, as well as stimulants such as coffee.
Your doctor may also want to interview your sleeping partner about your sleep patterns, as your partner may observe aspects of your behaviour during sleep of which you’re unaware.
He or she may also ask you and your partner to keep diaries of your sleep patterns for a few weeks.
In most cases, the cause will become apparent through your medical history and the physical examination. If there’s evidence of an additional sleep disorder, such as sleep apnoea, your doctor may recommend a sleep study, or "nocturnal polysomnography".
These studies are usually done in a sleep laboratory in a medical centre. You’ll have to spend the night in a hospital-type room while specialised machines will monitor your heart, lung and brain, as well as your muscle activity.
How can insomnia be prevented?
Insomnia can often be prevented by identifying and dealing with problems that could cause or exacerbate sleeplessness, such as underlying medical problems (e.g. depression or anxiety), or behaviours such as caffeine and alcohol consumption.
However, when treatment of medical or behavioural factors doesn’t improve the insomnia, or when there’s no apparent underlying cause (as in primary insomnia), your doctor may recommend other treatment methods.
Reviewed by Dr Irshaad Ebrahim, specialist neuropsychiatrist in sleep disorders at The London Sleep Centre and The Constantia Sleep Centre. FRCPsych. April 2018.