When is insomnia a medical problem worth treating?

A bad night vs. insomnia

Most people will have bad nights from time to time. Stress before a big event, a noisy neighbour, jet lag, illness, hot weather. These are normal and don’t need medical attention.

Insomnia — the medical condition — is different. It’s persistent. It happens even when you have plenty of opportunity to sleep. It affects how you function the next day. And it doesn’t resolve with reasonable willpower or one good night.

When is it “insomnia disorder”?

The clinical definition (DSM-5):

• Difficulty initiating sleep, maintaining sleep, or early-morning awakening
• The sleep problem occurs at least 3 nights per week
• Has been present for at least 3 months
• Causes significant distress or impairment in daytime function
• Not better explained by another sleep disorder, medical condition, medication, or substance

Shorter durations may still warrant treatment — the cutoff is somewhat arbitrary — but 3 months marks the line where it’s unlikely to resolve without specific intervention.

Why people don’t sleep

Psychological / behavioural

• Anxiety, depression, post-traumatic stress
• Worry about sleep itself (the anxiety becomes the cause)
• Conditioned hyper-arousal — the bedroom becomes associated with being awake
• Irregular schedule, shift work, jet lag

Medical

• Sleep apnoea (commonly overlooked — see below)
• Restless legs syndrome / periodic limb movement disorder
• Chronic pain
• Frequent urination at night (often prostate or pelvic causes)
• Hot flushes / night sweats (menopause, some medications)
• Reflux
• Asthma, chronic cough
• Thyroid problems (overactive)
• Restless legs — often associated with iron deficiency

Substance-related

• Caffeine, particularly in afternoon/evening
• Alcohol — reduces sleep quality even when it helps you fall asleep
• Stimulants (medications, cocaine)
• Withdrawal from sedatives or opioids

Mental health

Sleep and mental health are deeply intertwined. Insomnia is a symptom of depression and anxiety in many cases. Treating one usually improves the other.

The sleep apnoea problem

Obstructive sleep apnoea is grossly under-diagnosed. The pattern: the airway narrows and closes repeatedly during sleep, causing brief arousals to breathe. The person doesn’t remember the arousals but sleep architecture is destroyed.

Classic features:

• Snoring (loud, often with pauses)
• Waking unrefreshed
• Daytime sleepiness
• Morning headaches
• Witnessed pauses in breathing
• Often (not always) overweight
• More common in men, post-menopausal women, older adults

If this pattern fits, sleep apnoea needs proper assessment with a sleep study — not just “sleep hygiene advice.” Untreated sleep apnoea increases cardiovascular risk, road traffic accident risk, and has measurable effects on quality of life.

CBT-I — the gold standard

Cognitive behavioural therapy for insomnia is the evidence-based first-line treatment for chronic insomnia. It works better than medication long-term and avoids the side effects, dependency risk and rebound insomnia associated with sleep medication. The technique itself can cause short-term fatigue or irritability during the sleep-restriction phase, which we’ll talk through if it sounds right for you.

What it involves:

• Sleep restriction — counter-intuitively, spending less time in bed to consolidate sleep and rebuild sleep pressure
• Stimulus control — re-associating the bed with sleep (and only sleep)
• Cognitive restructuring — addressing thought patterns that maintain insomnia
• Sleep hygiene — the basics, properly applied
• Relaxation techniques

Delivered by a trained therapist over 4–8 sessions, or via well-validated digital programmes. NHS access is patchy; private CBT-I is available.

Sleep hygiene — the boring basics

Often dismissed because it’s well-known. Worth doing properly anyway.

• Consistent wake time — same time daily, including weekends
• Caffeine — cut off by lunch for sensitive people
• Alcohol — limit, especially in the 3 hours before bed
• Exercise — regular, ideally not in the 2–3 hours before bed
• Light exposure — bright light in the morning, dim in the evening
• Bedroom environment — cool (around 18°C), dark, quiet
• Screen use — the issue is more stimulation than blue light; reduce engagement, not just blue light
• Wind-down routine — 30–60 minutes of low-stimulation activity before bed
• Don’t clock-watch — turn the clock away from view
• If you’re not sleeping — get up after about 20 minutes, do something quiet, return to bed when sleepy

Medication — when and when not

Sleep medications have a role but are over-relied upon.

Reasonable use

• Short-term during acute stressors (bereavement, major life event)
• Bridging while waiting for CBT-I
• Specific situations (jet lag, shift work transitions)

Problematic use

• Months or years of regular use (tolerance, dependence, withdrawal-related insomnia)
• Use as substitute for addressing underlying causes
• Higher doses than necessary
• Some older medications (with hangover effects, falls risk in older adults)

UK law prevents naming specific prescription medications on this website. We discuss specific options at consultation if appropriate.

When to see a doctor

• Persistent insomnia for 3+ months
• Significant daytime impact (concentration, mood, function)
• Snoring + unrefreshing sleep
• Suspected sleep apnoea
• Insomnia with depression or anxiety
• Long-term use of sleep medication you want to reduce
• Significant restless legs
• Sleep problems following a specific event or medication change

A 4-week reset plan

If you’d like to try a structured approach before seeing a doctor:

Week 1: Audit

• Keep a brief sleep diary — bedtime, time to fall asleep, awakenings, wake time, daytime sleepiness, caffeine, alcohol, exercise
• Identify obvious factors

Week 2: Adjust the basics

• Fix wake time
• Cut caffeine after lunch
• Add a wind-down hour
• Address one specific issue (alcohol, screens, partner snoring)

Week 3: Implement core CBT-I principles

• Stimulus control — bed only for sleep
• If awake more than 20 minutes, get up, do something quiet, return when sleepy
• Restrict time in bed initially — only spend as long in bed as you’re typically sleeping (with minimum 5 hours)

Week 4: Assess

If significantly improved — continue. If not — book an appointment. Don’t persist alone with chronic insomnia; treatments exist.

See our insomnia condition page for more detail.