If you have lived through trauma, you may have noticed that sleep stopped feeling safe long before anyone used the word “insomnia” to describe what was happening to you. You lie down exhausted, and instead of drifting off, your body goes on alert. You wake at 3am with your heart racing, or you dread going to bed because you know what might be waiting in your dreams. Months or years after the event itself, the sleep problems often remain the most stubborn symptom of all.
This is extremely common. Sleep disturbance is one of the earliest and most persistent features of post-traumatic stress disorder (PTSD), and for many people it continues long after other symptoms have eased. The good news is that this type of insomnia responds well to a specific, structured treatment — and you don’t have to keep white-knuckling your way through sleepless nights to get there.
Why trauma disrupts sleep so deeply
Sleep and the trauma response share the same biological wiring, which is part of why the two become so entangled. When the nervous system has been shaped by a threatening or overwhelming experience, it tends to stay primed to detect danger — including at night, when the brain is normally supposed to let its guard down.
Researchers describe sleep disturbance as one of the earliest signs of PTSD, often appearing alongside nightmares, difficulty falling asleep, and fragmented rapid-eye-movement (REM) sleep, the sleep stage in which most vivid dreaming occurs. Some studies have even found that people who already had frequent nightmares before a traumatic event were more likely to go on to develop PTSD afterwards, suggesting sleep and trauma responses can feed into one another in both directions.
For a condition that affects an estimated 1 in 14 people at some point in their life, this overlap matters. It means that for a great many people, treating the insomnia properly isn’t a side issue — it’s central to recovery.
The cycle that keeps PTSD-related insomnia going
In the early days after a traumatic event, poor sleep is an entirely understandable, short-term response to a nervous system in overdrive. The trouble is that a few other things usually happen alongside it that turn a short-term problem into a long-term one:
- The bed stops feeling safe. If nightmares, night waking, or panic have happened in bed before, your brain starts to associate the bed itself with alertness rather than rest.
- Bedtime becomes something to brace for. Many people start delaying sleep, scrolling on their phone, or keeping lights or the television on, as a way of avoiding the vulnerable feeling of lying still in the dark.
- The body stays in a state of hyperarousal. A racing heart rate, muscle tension, and a mind that won’t switch off are hallmark features of PTSD, and they are also the exact opposite of what the body needs to fall asleep.
- Daytime naps and erratic hours creep in to make up for lost sleep, which weakens the body’s natural drive to sleep at night.
Within a few months, the original trauma may have settled, or treatment for it may be underway, but the insomnia has taken on a life of its own — kept going now by habits, associations, and anxiety about sleep itself, rather than by the original threat. This is exactly the kind of insomnia that CBT-I (cognitive behavioural therapy for insomnia) is designed to treat.
Nightmares, night waking, and the fear of falling asleep
Nightmares deserve a special mention, because they’re one of the most distressing parts of PTSD-related sleep disruption. They affect the large majority of people with PTSD, tend to occur during REM sleep, and become more frequent in the second half of the night — which is often exactly when people with PTSD report the most trouble staying asleep.
Over time, many people develop a genuine fear of sleep itself: not wanting to “go under” in case a nightmare comes, or dreading the vulnerable, out-of-control feeling of being asleep at all. This fear is understandable, but it also drives the nervous system further into alertness at the exact moment it needs to relax. We cover this pattern in more depth in our piece on why you wake up in the middle of the night, and the broader anxiety-around-sleep pattern is explored further in our guide to how to fall asleep faster when your mind won’t settle.
Why sleeping pills aren’t the long-term answer
It’s understandable to want quick relief, and sleeping medication can have a place in the short term, particularly in the immediate aftermath of a traumatic event. But medication doesn’t resolve the underlying hyperarousal or the learned associations between bed and danger that keep PTSD-related insomnia going, and some medications can interfere with the quality of REM sleep in ways that may not help trauma processing. If you are currently taking sleep medication, never stop or change your dose on your own — always speak to your GP first, who can advise on the safest way forward alongside other treatment such as CBT-I. For more on this, see our guide to insomnia treatment without medication.
How CBT-I treatment helps when trauma is involved
NICE (the National Institute for Health and Care Excellence) recommends CBT-I as the first-line treatment for chronic insomnia in adults, to be offered before or alongside medication. CBT-I works by directly addressing the mechanisms that keep insomnia going — including the ones that are especially active after trauma:
- Rebuilding the bed-sleep association through structured techniques that help your brain relearn that bed means sleep, not alertness.
- Reducing hyperarousal with evidence-based relaxation and wind-down strategies tailored to your situation, rather than generic “sleep hygiene” tips.
- Addressing anxiety about sleep itself, including the fear of nightmares or of losing control while asleep.
- Stabilising your sleep-wake schedule so your body’s natural sleep drive can reassert itself, rather than being disrupted by naps or erratic hours.
Research specifically in people with PTSD and insomnia backs this up. A 2025 randomised controlled trial published in the Journal of Clinical Psychiatry gave veterans with both conditions either CBT-I or standard sleep hygiene advice, alongside trauma-focused therapy, and found meaningful sleep improvements with the CBT-I approach. A related 2024 military study combined CBT-I with structured nightmare treatment alongside trauma-focused therapy, and found this combination outperformed trauma therapy on its own for improving both sleep and PTSD symptoms. The research base is still growing, but the direction is consistent: treating the insomnia directly, rather than hoping it resolves once the trauma is processed, tends to produce better sleep outcomes.
To understand the mechanics of why this approach works even when anxiety or trauma is driving the sleeplessness, our page on why CBT-I works goes into more detail.
What to expect from trauma-informed CBT-I
If you’re considering CBT-I alongside trauma-related sleep problems, a few things are worth knowing:
- It’s structured, not just advice. A good clinician will take a full sleep history, including how your sleep problems relate to your trauma history, before building a personalised plan.
- It can run alongside trauma therapy. CBT-I doesn’t require you to have finished trauma-focused treatment first — the two can often be worked on in parallel, in coordination with whoever is supporting you with the trauma side.
- Nightmares may need a specific technique. If vivid, recurring nightmares are a major part of the picture, a clinician experienced in trauma-related sleep problems can combine CBT-I with nightmare-focused strategies such as imagery rehearsal.
- Progress is usually gradual but steady. Many people notice initial improvements in a few weeks, with fuller results building over a matter of months as new sleep patterns bed in.
This is covered from a broader angle in our complete guide to insomnia, which walks through what structured treatment generally involves.
When to seek additional support
If your sleep problems are tied to a traumatic experience, it’s worth speaking to your GP, particularly if you notice flashbacks, intense avoidance of reminders of the event, low mood, or thoughts of harming yourself. NICE guidance recommends that people with PTSD be offered trauma-focused psychological treatment, such as trauma-focused CBT or EMDR, and your GP can refer you to NHS talking therapies or a specialist trauma service for this. Treating the trauma itself and treating the insomnia are not either/or — many people benefit most from doing both, with each piece of support working alongside the other.
Frequently asked questions
Can PTSD cause insomnia even years after the traumatic event?
Yes. Sleep disturbance often persists long after other PTSD symptoms have eased, partly because habits and anxiety around sleep take on a life of their own over time. This is treatable with CBT-I regardless of how long ago the trauma occurred.
Do I need to finish trauma therapy before starting CBT-I?
No. CBT-I can often run alongside trauma-focused treatment, and many people find that improving their sleep gives them more resilience to engage with trauma therapy too. Your clinicians can coordinate the two.
Will CBT-I stop my nightmares?
CBT-I primarily targets insomnia, but it’s often combined with specific nightmare-focused techniques, such as imagery rehearsal therapy, when nightmares are a significant part of the sleep problem. A clinician experienced in trauma-related sleep issues can tailor this to you.
Is medication ever appropriate for PTSD-related insomnia?
Medication can have a role, particularly in the short term, but it isn’t a long-term solution on its own and doesn’t address the underlying patterns driving the insomnia. Always speak to your GP before starting, changing, or stopping any sleep medication.
Taking the next step
Insomnia after trauma can feel like something you’ll just have to live with, especially if you’ve already done the hard work of processing what happened to you. It isn’t something you have to manage alone or endure indefinitely. Structured insomnia treatment that directly targets the hyperarousal, the bed-sleep association, and the anxiety around sleep can bring real, lasting change — often even while trauma-focused therapy is still ongoing.
If this sounds like your experience, a good first step is our free insomnia self-assessment, which takes a few minutes and gives you a clearer picture of what’s driving your sleep problems. You’re also welcome to get in touch to discuss your situation directly.