Cannabis for insomnia: what studies and the 2026 guideline say

What does the 2026 Cochrane review show on cannabis for insomnia?

The Cochrane review by Varela and colleagues (published on 13 October 2026) is currently the most thorough analysis. It included nine randomised trials with 537 adults aged 18 to 76, mostly with primary insomnia. Eight trials compared cannabis with placebo, one with an antidepressant.

Compared with placebo, medical cannabis probably had no effect, or only a small effect that is not clinically meaningful, on sleep quality and satisfaction with sleep, on total sleep time and on daytime functioning. On average, sleep duration was about eight minutes longer, with great uncertainty. Unwanted effects were more common with cannabis.

The authors rate their confidence in the results as low to very low, among other reasons because of small trials, inconsistent results and a high risk of bias. The German pharmacists' journal Pharmazeutische Zeitung summarised the result in October 2026 as little evidence for cannabis in insomnia.

Who took part in the sleep studies?

The trials are small and designed differently. Around three quarters of participants were women. Three trials looked at acute insomnia, six at chronic insomnia. Only two trials tested approved finished medicines; seven used preparations made in a pharmacy. The literature search ran until April 2025.

Clinically relevant means: a difference is large enough for people to notice it in everyday life. A difference can show up in the statistics and still be too small to matter for sleep. That is exactly the case with cannabis and insomnia: the measured differences were small, varied widely between studies and in several cases also included zero.

The picture was clearer for side effects. In the crossover trials, in which the same people received cannabis and placebo one after the other, 37 participants had unwanted effects only with cannabis, and nobody had them only with placebo.

How does THC affect sleep?

THC may shorten the time it takes to fall asleep, but may worsen sleep quality in the long run. This is how a review by Babson and colleagues (2017) summarises the research, which overall is still at an early stage and shows mixed results.

For CBD there are first, preliminary signals from small studies, but no robust evidence of a benefit in insomnia. How THC and CBD differ in principle is explained in CBD vs THC: the difference.

What does the German S3 guideline on insomnia recommend?

The German S3 guideline on insomnia in adults (2025 update) names cognitive behavioural therapy for insomnia (CBT-I, in German KVT-I) as the first treatment option for everyone affected. This also applies when the sleep disorder occurs together with a physical or mental illness.

Medicines only come into question if CBT-I does not work well enough or is not feasible, and in older people only with great caution. The guideline lists cannabinoids merely among options that could be studied more in future, because they still lack a solid empirical basis. It does not recommend cannabis.

What is insomnia?

Insomnia is a sleep disorder with problems falling asleep or staying asleep, or waking too early, which leads to dissatisfaction with sleep and to impairment during the day. Fixed thresholds for the time to fall asleep or for sleep duration are not needed for the diagnosis.

Under the ICD-10 classification, symptoms must have lasted for at least one month, and for chronic insomnia under ICD-11 for at least three months. Poor sleep can also be caused by other conditions, such as sleep apnoea, restless legs, chronic pain, depression or side effects of medicines.

Why do some people feel they sleep better with cannabis?

In the short term, THC can make you tired and make falling asleep feel easier. But that is not the same as restful sleep over weeks and months, which is what studies measure.

A randomised trial from the USA (Gilman and colleagues, 2022) shows both sides: adults who received immediate access to cannabis through a medical marijuana card reported fewer sleep problems after twelve weeks than the comparison group. At the same time, 17.1% of them developed a cannabis use disorder, compared with 8.6% in the comparison group. Pain, anxiety and depressive symptoms did not improve.

Often the reason for poor sleep is another illness. In people with chronic pain, a BMJ meta-analysis found a small improvement in sleep quality with cannabis-based medicines. In that case it is not the sleep disorder itself that is being treated, but part of the underlying illness. More in Cannabis for chronic pain.

Tolerance: why the sleep-promoting effect can fade

With regular use, the body gets used to THC. Regular use leads to a down-regulation of the CB1 receptors in the brain that THC acts on. The same amount then works less well, and the wish for more can easily arise.

For sleep this means: what made you tired at first is often no longer enough after a few weeks. Increasing the amount raises side effects and the risk of dependence.

Cannabis as a sleep aid: how high is the risk of dependence?

People who use cannabis regularly to fall asleep often take it daily and over a long time. Exactly this pattern increases the risk of a cannabis use disorder. A meta-analysis by Leung and colleagues (2020) estimates that about 22% of people who use cannabis develop such a disorder. In young people with weekly or daily use, the risk of dependence rose to about 33% in cohort studies.

On top of that, sleep becomes a reason to keep using: if you sleep badly without cannabis, you always have a reason to carry on. Warning signs are an increasing amount, unsuccessful attempts to take a break and the feeling that you cannot get through a night without cannabis. Then an open conversation with your doctor is the right step.

Why even approved sleeping pills are only used briefly

The caution around cannabis is not a special case. The S3 guideline also advises against long-term treatment with approved sleeping pills. Benzodiazepines and related substances are only considered effective for up to four weeks, orexin receptor antagonists should not be given beyond one year, and melatonin not long term.

The reason is similar for all of them: habituation, side effects during the day and problems when stopping. CBT-I therefore targets the causes that keep the sleep disorder going. For cannabis, proof of a clinically relevant benefit is missing in the first place.

Rebound and withdrawal insomnia: what happens when you stop?

After longer, regular use, sleep problems are among the typical signs of cannabis withdrawal. They often come with irritability, restlessness, low mood, cravings and very vivid dreams.

According to a review by Bonnet and Preuss (2017), the down-regulated CB1 receptors start to recover in the first two days without cannabis, and after about four weeks they work normally again. This can serve as a rough time frame for withdrawal symptoms. How strong they are depends, among other things, on the previous amount.

Sleep in particular can turn into a cycle: you take a break, sleep worse, take that as proof that you cannot sleep without cannabis and start again. A planned stop with medical support can break this cycle. How that works is explained in Cannabis withdrawal symptoms. The German S3 guideline on cannabis-related disorders (2025) also describes help for people who cannot manage this on their own.

Cannabis in the evening: what does it mean for the next morning?

If you take cannabis in the evening, you may still be tired or slower the next morning. How long THC acts in the body and remains detectable depends on form, amount and frequency, more in How long does THC stay in your system?.

Do not drive if you feel impaired or are unsure, especially during the titration phase. What applies on German roads is explained in the guide Driving with a cannabis prescription.

Take care when combining it with sleeping pills, sedatives, certain painkillers or alcohol. Tiredness, drowsiness and dizziness can reinforce each other. Always tell your doctor and your pharmacy (Apotheke) about every medicine you take. An overview of common unwanted effects is in Medical cannabis side effects.

How does cognitive behavioural therapy for insomnia work?

CBT-I is a psychotherapeutic treatment focused on sleep. According to the guideline, it consists of psychoeducation, relaxation methods, sleep restriction, stimulus control and cognitive therapy. It is offered as individual or group therapy or as a digital health application (DiGA). Approved digital programmes are listed in the directory of the German Federal Institute for Drugs and Medical Devices (BfArM).

Newer meta-analyses summarised in the guideline show large effects on the severity of the sleep disorder. In follow-ups of up to one year, small to moderate effects remain. The components often only work after a few weeks, but without getting used to a substance.

1. Psychoeducation: understand how sleep is regulated and learn that bad nights are followed by good ones again.
2. Sleep diary: record bedtimes and sleep times for at least one week.
3. Sleep restriction: with guidance, temporarily cut time in bed down to the actual sleep time and then extend it again step by step.
4. Stimulus control: link the bed with sleeping again instead of lying awake.
5. Cognitive techniques and relaxation: reduce brooding and question stressful beliefs about sleep.

Stimulus control and the worry chair: two techniques in detail

Stimulus control is based on the idea that for many people the bed has become linked with being awake. The aim is to spend as little time as possible lying awake in bed. The guideline names simple rules for this.

Against brooding at night, the guideline describes the so-called worry chair (Gedankenstuhl): a few hours before bed, you take 15 to 20 minutes to think deliberately and with a focus on solutions about the topics that would otherwise go round in your head at night. Sleep restriction is effective but demanding and belongs under professional supervision.

• Only go to bed in the evening when you feel sleepy.
• Use the bed only for sleep and sex, not for watching TV, reading or smoking.
• After about 15 minutes of lying awake, get up, do something calm and only return when you are sleepy.
• Get up at the same time every morning.
• Do not lie down during the day.

Rules for healthy sleep

Simple behavioural rules are part of psychoeducation. On their own they rarely resolve chronic insomnia, but they create good conditions. The S3 guideline lists these points, among others.

• No caffeinated drinks after lunch
• Largely avoid alcohol and never use it as a sleep aid
• No heavy meals in the evening
• Be physically active regularly
• Avoid exciting activities and bright light before bed
• Keep a personal bedtime ritual
• A cool, quiet and dark bedroom
• Do not look at the clock at night

Sleep problems with other illnesses

Many physical and mental illnesses disturb sleep. The guideline names, among others, epilepsy, multiple sclerosis, polyneuropathy, cardiovascular and lung diseases, sleep apnoea, chronic gastrointestinal and kidney diseases, and severe itching in skin conditions.

Even then, according to the guideline, CBT-I is the first treatment option, and the underlying illness should be treated in line with its own guidelines. In older people, the guideline advises using sleep medication only with great caution.

When should you have sleep problems checked by a doctor?

Persistent sleep problems should be checked by a doctor before medicines are discussed. In Germany your first port of call is usually your GP (Hausarzt). The guideline stresses that physical and mental illnesses and substances that disturb sleep should be asked about actively. In sleep laboratory tests, sleep apnoea and leg movements at night turn up surprisingly often in people with insomnia.

If you have thoughts of not wanting to live any more, get help immediately: call 112 or the TelefonSeelsorge crisis line on 0800 111 0 111, 0800 111 0 222 or 116 123, around the clock and free of charge.

• Loud snoring with pauses in breathing, or falling asleep unintentionally during the day
• Restlessness or tingling in the legs in the evening
• Sleep problems on several nights a week for months
• Persistent low mood, brooding or anxiety
• Sleep problems after starting a new medicine

When can medical cannabis still be a topic?

If sleep problems are part of another serious illness, such as chronic pain, spasticity in multiple sclerosis or in palliative care, a medical assessment in the individual case may concern the underlying illness. According to the guideline, the sleep disorder itself is not an indication for cannabis.

What matters then is an honest weighing of benefits and risks, a clear goal and documentation, for example in a treatment diary. Whether a treatment is considered at all is always decided by the treating doctor after an individual assessment.

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