A long-acting benzodiazepine

Diazepam

A long-acting benzodiazepine used short-term for severe anxiety, certain muscle spasms and some seizure situations; it causes drowsiness and dependence with regular use.

What is Diazepam?

Diazepam is a long-acting benzodiazepine used for short-term relief of severe anxiety, as a muscle relaxant, and in some seizure and alcohol-withdrawal situations. It causes drowsiness and, with regular use, dependence, so it is intended only for short courses. It should not be combined with alcohol and must not be stopped suddenly after regular use.

Class: Benzodiazepines & Z-drugs · Brands: Valium

Education and reference only. This is a plain-language guide to Diazepam — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.

Written by Meds Global Health Clinical Team · Clinically reviewed by Dr Muhammad Suffyan, MB BS, Founder & Clinical Director · Last reviewed · How we review
Class: Benzodiazepines & Z-drugs → Brands: Valium
Diazepam (Benzodiazepines & Z-drugs) — Meds Global Health reference card with 2D molecular structure
Diazepam — Benzodiazepines & Z-drugs. The image shows the active ingredient's 2D molecular structure.

What it is

Diazepam is one of the best-known benzodiazepines in the UK. It is used short-term for severe or disabling anxiety, as a muscle relaxant for painful muscle spasm, and in certain situations such as some types of seizure and alcohol withdrawal. It is long-acting, meaning it stays in the body for a relatively long time, which can give smooth cover but also lingering next-day effects. Because of the risk of tolerance and dependence, it is intended for short courses rather than ongoing daily use.

How it works

Diazepam enhances the effect of GABA, the brain's main calming chemical messenger. By making GABA's natural braking action stronger, it reduces over-activity in the nervous system, which eases anxiety, relaxes muscles and raises the threshold for seizures. The same calming, sedating action explains its drowsiness and its potential to depress breathing when combined with other sedatives.

Company & origin

Originated / developed by: Developed by Hoffmann-La Roche..

Diazepam was discovered by Leo Sternbach at Roche and introduced in the 1960s under the brand name Valium.

What it treats

Conditions Diazepam is used for

Anxiety disordersPersistent, excessive worry and physical tension that interfere with daily life — treated …

Practical use

How to take Diazepam

General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.

  • Use it only for the short period your prescriber advises — it is not intended for long-term daily use because of dependence.
  • Expect drowsiness; do not drive or operate machinery until you know how it affects you, and remember effects can carry into the next day.
  • Do not drink alcohol while taking it, as this dangerously increases sedation and slowed breathing.
  • Do not stop suddenly after taking it regularly — speak to your prescriber, who will reduce it gradually to avoid withdrawal.
  • Avoid taking it with other sedating medicines such as opioids or sleeping tablets unless specifically advised.
  • Tell your prescriber if it stops working as well, rather than taking more on your own.

Weighing it up

Advantages & disadvantages of Diazepam

Advantages

  • Acts quickly and reliably to calm severe anxiety and relax muscle spasm.
  • Long-acting, giving smoother, steadier cover than some shorter-acting alternatives.
  • A familiar, well-understood medicine useful in specific situations such as seizures and alcohol withdrawal.

Disadvantages

  • Causes drowsiness and can impair driving, memory and concentration.
  • Leads to tolerance and dependence with regular use, so it is only for short courses.
  • Must be reduced gradually, as sudden stopping after regular use can cause withdrawal including seizures.
  • Long-acting effects can linger into the next day and increase falls and confusion in older people.

Practical use

Good to know

It is meant for short-term use only, because the body becomes used to it quickly and dependence can develop within a few weeks of regular use. It commonly causes drowsiness and can affect concentration and driving. After regular use it must not be stopped suddenly, as this can cause withdrawal effects including rebound anxiety, sleep problems and, rarely, seizures — it is reduced gradually. Do not drink alcohol with it. Because it is long-acting, sedation and 'hangover' effects can carry over into the next day, which matters particularly for older people who are more sensitive to falls and confusion.

Who should not take it / use with caution

  • People with significant breathing problems, severe sleep apnoea or acute severe respiratory weakness, where it can dangerously slow breathing.
  • People with a history of alcohol or drug dependence need particular caution because of the dependence risk.
  • Used with caution in older or frail people, significant liver impairment, myasthenia gravis, and in pregnancy and breastfeeding.

Monitoring

  • Regular review to keep use short and to plan stopping.
  • Watching for excessive drowsiness, falls (especially in older people) and signs of dependence.
  • A gradual reduction plan rather than abrupt stopping after regular use.

Side effects

  • Drowsiness, tiredness and reduced concentration.
  • Muscle weakness, unsteadiness and dizziness, with a higher risk of falls in older people.
  • Memory problems and, occasionally, confusion or paradoxical agitation.
  • With regular use: tolerance, dependence and withdrawal effects if stopped abruptly.

Key interactions

  • Alcohol and other sedatives (opioids, sleeping tablets, sedating antihistamines, gabapentin/pregabalin) — additive drowsiness and dangerous breathing depression.
  • Strong opioids in particular carry a serious combined risk and should only be used together with caution.
  • Some medicines that affect liver enzymes can raise or lower its levels; tell your pharmacist about all your medicines.

Available as: Available as tablets, an oral solution and other formulations used in specific settings.

Answers

Diazepam: frequently asked questions

How long can I take diazepam for?

It is intended for short-term use only, often just a couple of weeks, because dependence can develop quickly. Your prescriber will agree the shortest sensible course with you.

Can I stop diazepam suddenly?

No, not after regular use. Stopping suddenly can cause withdrawal including rebound anxiety, sleep problems and, rarely, seizures. It is reduced gradually with your prescriber.

Can I drink alcohol with diazepam?

No. Alcohol greatly increases drowsiness and slowed breathing when combined with diazepam, which can be dangerous.

Will it make me drowsy the next day?

It can. Diazepam is long-acting, so sedation and a 'hangover' feeling can carry into the next day, which is especially important if you drive.

Is diazepam addictive?

Yes, dependence can develop with regular use, which is why it is used short-term and reduced gradually rather than stopped abruptly.

The wider class

About Benzodiazepines & Z-drugs

Diazepam belongs to the benzodiazepines & z-drugs class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.

Benzodiazepines and Z-drugsCalming and sleep medicines for short-term use — effective but habit-forming. ZopicloneA Z-drug sleeping tablet used for short-term treatment of insomnia; it can cause next-day …LorazepamA benzodiazepine used for short-term relief of severe anxiety and a number of other situat…TemazepamA benzodiazepine used for the short-term treatment of insomnia, helping people who are hav…ZolpidemA 'Z-drug' used for the short-term treatment of insomnia, helping people fall asleep when …ClonazepamA benzodiazepine used to help control certain types of epilepsy; it can cause drowsiness a…NitrazepamA long-acting benzodiazepine sleeping tablet for short-term, severe insomnia; it can cause…OxazepamA short-acting benzodiazepine used only for the short-term relief of severe anxiety, effec…ClobazamA benzodiazepine used mainly as an add-on treatment to help control epileptic seizures, wh…ChlordiazepoxideA benzodiazepine used mainly for the short-term management of alcohol withdrawal.…LormetazepamA benzodiazepine sleeping tablet for the short-term treatment of insomnia.…ZaleplonA very short-acting Z-drug sleeping tablet for short-term insomnia.…BuspironeAn anti-anxiety medicine that eases generalised anxiety over time, without the dependence …RemimazolamA short-acting benzodiazepine given into a vein to provide sedation during procedures, und…AlprazolamA short-acting benzodiazepine sometimes used for anxiety or panic, but not a first-line UK…EszopicloneA 'Z-drug' sleeping tablet used for short-term help with insomnia.…MidazolamA short-acting benzodiazepine used for sedation during procedures, to stop prolonged seizu…TriazolamA short-acting benzodiazepine used for the short-term treatment of severe insomnia.…EstazolamA benzodiazepine sleeping tablet used for the short-term treatment of insomnia.…

Browse by body system

Mental healthConditions and medicines for mood, anxiety, psychosis, sleep and dependence — used alongsi…

Authoritative sources

  • BNF
  • NICE CKS

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