Benzodiazepines and Z drugs
Peer reviewed by Dr Hayley Willacy, FRCGP Last updated by Dr Colin Tidy, MRCGPLast updated 18 Nov 2022
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A short course of a benzodiazepine or a Z drug may be prescribed if a medicine is felt necessary to help with sleeping difficulty (insomnia).
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What are benzodiazepines?
Benzodiazepines are a group of medicines that are sometimes used to treat anxiety, sleeping problems and other disorders. Examples include diazepam, lorazepam, chlordiazepoxide, oxazepam, temazepam, nitrazepam, loprazolam, lormetazepam, clobazam and clonazepam.
How do benzodiazepines work?
Benzodiazepines work by affecting the way certain brain chemicals (neurotransmitters) transmit messages to certain brain cells. In effect, they decrease the excitability of many brain cells. This has a calming effect on various functions of the brain.
What are Z drugs?
Medicines called zolpidem and zopiclone are commonly called the Z drugs.
Is zopiclone a benzodiazepine?
Strictly speaking, Z drugs are not benzodiazepines but are another class of medicine. However, they act in a similar way to benzodiazepines. (They have a similar effect on the brain cells as benzodiazepines.) Z drugs have similar long-term usage problems as benzodiazepines.
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What are benzodiazepines and Z drugs used for?
Benzodiazepines for anxiety
Symptoms of anxiety include: agitation, tension, irritability, the sensation of having a 'thumping heart' (palpitations), shakiness, sweating, excess worry, sleeping badly, poor concentration, fast breathing and sometimes a knotted feeling in the stomach and other muscles.
There are various causes of anxiety. Sometimes it is a sudden life crisis such as a bereavement or redundancy. Some people have an anxious personality and feel anxious fairly often. Sometimes anxiety can be one of the symptoms of depression. Although most people will feel anxious at some time, sometimes the symptoms become prolonged and distressing.
Treatments for anxiety include: relaxation exercises, anxiety management courses and cognitive therapy and behavioural therapy. Simply talking things over with a friend, counsellor, or with members of a self-help group may also help. However, if symptoms become very severe, you may occasionally be advised to take a benzodiazepine medicine for a short time.
Benzodiazepines and Z drugs as sleeping tablets
A short course of a benzodiazepine or a Z drug may be prescribed if a medicine is felt necessary to help with sleeping difficulty (treatment for insomnia). However, there are other ways of helping to get a good night's sleep. See also the separate leaflet called Insomnia (Poor Sleep).
Other uses of benzodiazepines
A dose of benzodiazepines is often given as a 'pre-med' to reduce anxiety before an operation. A large dose is commonly given as a sedative during medical procedures that may cause anxiety or discomfort. The medicine not only reduces anxiety but also has an amnesic effect. This means that you do not remember much about the procedure afterwards.
Some benzodiazepines are occasionally used to treat muscle spasm and certain types of epilepsy as they can prevent fits (seizures). Others are used to help people who are dependent on alcohol and trying to stop. See also the separate leaflet called Medicines for Drug Dependence.
How effective are benzodiazepines and Z drugs?
If you are not used to taking benzodiazepines or Z drugs, the first doses are usually good at easing symptoms of anxiety or promoting sleep. A benzodiazepine does nothing to remove any underlying cause of anxiety such as a life crisis. However, if your symptoms are eased, you may be able to cope better with any problems.
Benzodiazepines and Z drugs work best in situations where anxiety or sleeping difficulty is expected to last only a short while. They are not so useful if you have an ongoing anxious personality or long-term sleeping difficulty. However, a short course may help you over a particularly bad spell.
You can usually stop a benzodiazepine or a Z drug without any problems if you take it for just a short period of time (no more than 2-4 weeks).
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Why should benzodiazepine and Z drugs be used only for a short time?
When benzodiazepines were first used they were thought to be safe. The problems with their long-term use were not known. In 1981, benzodiazepines were the most commonly prescribed medicines in western countries. It was because benzodiazepines worked so well to ease symptoms of anxiety and poor sleep that many people came back for more. Some people started to take them regularly.
However, it is now known that if you take a prescribed benzodiazepine or a Z drug for more than 2-4 weeks, you may develop problems (see below). Therefore, most doctors will now only prescribe benzodiazepines and Z drugs for a short period.
What happens if you use a benzodiazepine or a Z drug for longer?
Tolerance
If you take a benzodiazepine or Z drug regularly, the helpful effect on easing anxiety or in helping sleep usually lasts for a few weeks. However, after a few weeks, the body and brain often become used to the benzodiazepine or Z drug.
The medicine then gradually loses its effect. The initial dose then has little effect. You then need a higher dose for it to work. In time, the higher dose does not work and you need an even higher dose and so on. This effect is called tolerance.
Dependence
There is a good chance that you will become addicted to (dependent on) a benzodiazepine or a Z drug if you take it for more than four weeks. This means that withdrawal symptoms occur if the tablets are stopped suddenly. In effect, you need the medicine to feel normal. Possible withdrawal symptoms include:
Psychological symptoms - such as anxiety, panic attacks, odd sensations, feeling as if you are outside your body, feelings of unreality, or just feeling awful. Rarely, a serious mental breakdown can occur.
Physical symptoms - such as sweating, being unable to sleep, headache, tremor, feeling sick (nausea), the sensation of having a 'thumping heart' (palpitations), muscle spasms and being oversensitive to light, sound and touch. Rarely, convulsions occur.
In some cases the withdrawal symptoms seem like the original anxiety symptoms.
The duration of withdrawal symptoms varies but often lasts up to six weeks and sometimes longer. Withdrawal symptoms may not start for two days after stopping the tablet and tend to be worst in the first week or so. Some people have minor residual withdrawal symptoms for several months.
Therefore, you may end up taking the medicine to prevent withdrawal symptoms but, because of tolerance, the medicine is no longer helping the original anxiety or sleeping problem. But note: you are unlikely to become dependent on a benzodiazepine or a Z drug if you take it for a short period only.
The National Institute for Health and Care Excellence (NICE) has published guidance on safe prescribing and stopping medicines that can lead to addiction or withdrawal symptoms in adults. They have concentrated on benzodiazepines and Z drugs which are often used for sleep issues, as well as some medication used for pain relief (opioids, gabapentin and pregabalin).
Before they prescribe, your doctor will take into account:
If other methods or medications that are not addictive have been tried.
Issues that could lead to you becoming addicted to the medication
That you have all the information you need to make a decision.
What you should know when starting a medication:
The type of medication and why it has been prescribed for you.
The starting dose and when doses will be changed if needed.
The side effects and how long they may last.
The person you should contact if you have any queries or concerns.
How long the medication will take to work and how long you will stay on it for.
How long the prescription given is for - eg, seven days, four weeks.
The risks of addiction and overdose.
When you will have a review.
Your doctor may stop the medication if:
There is no benefit or it is no longer helping you.
There are symptoms or signs of addiction.
Your illness is better.
There are more harms than benefits to taking the medication.
You, as a patient, want to stop the medication.
The doctor will stop the medication slowly. They will discuss with you how to do this, taking into account issues that may make stopping the medication difficult.
Stopping benzodiazepines
If you are on medications such as lorazepam or nitrazepam, you may be switched to diazepam. Diazepam has a longer half-life, meaning it will stay in your body longer reducing any withdrawal effects. Cognitive behavioural therapy (CBT) alongside withdrawing from a benzodiazepine can also help manage symptoms. Your doctor may refer you for CBT whilst stopping this type of medication.
For further reading, see the NICE guidance reference below (NICE NG215 Medicines associated with dependence or withdrawal symptoms: safe prescribing and withdrawal management for adults).
Some other possible problems with benzodiazepines and Z drugs
Even if you take a benzodiazepine or Z drug for a short time, you may feel drowsy during the daytime. Some people, especially older people, are at greater risk of having a fall and injury because of the drowsiness. If you drive, you may be more likely to be involved in a car crash. Some people have described themselves as being in a zombie state when they were taking a benzodiazepine on a long-term basis.
For a full list of possible side-effects of benzodiazepines, or whilst taking any tablet, read the leaflet that comes with the packet of tablets.
Benzodiazepines and Z drugs and the law
Benzodiazepines and Z drugs can sometimes be misused by people taking drugs for recreational purposes. The Misuse of Drugs Act was a law passed in 1971 in the UK to try to prevent the use of harmful drugs. It divides drugs into three categories - A, B or C, depending on how dangerous they are thought to be. Each of the categories then has different penalties for those convicted of use or supply. Benzodiazepines and Z drugs are classed as Class C drugs. This means it is illegal to be in possession of them if they have not been prescribed for you by a doctor. People found in possession illegally, or attempting to supply them to others, could face a fine or a prison sentence. There are also special rules for doctors prescribing them.
Driving
People on normal doses of benzodiazepines and Z drugs prescribed by their doctor do not need to inform the Driver and Vehicle Licensing Agency (DVLA). However, if you are taking higher doses than recommended, or taking them without prescription, your driving licence would be taken away.
What if I have been taking a benzodiazepine or a Z drug for a long time?
If you have been taking a benzodiazepine or a Z drug for over four weeks and want to come off it, it is best to discuss the problem with a doctor. Some people can stop taking benzodiazepines or Z drugs with little difficulty.
However, many people develop withdrawal symptoms if they suddenly stop taking a benzodiazepine or a Z drug. To keep withdrawal effects to a minimum, it is often best to reduce the dose of the medicine gradually over a number of weeks or months before finally stopping it. Your doctor will advise on dosages, timescale, etc.
How should I stop taking a long-term benzodiazepine or Z drug?
If you have been taking a benzodiazepine or Z drug for over four weeks and want to stop it, it is best to discuss the problem with a doctor.
Some people can stop taking benzodiazepines and Z drugs without any difficulty, as they have only minor withdrawal effects which soon ease off. However, for a lot of people the withdrawal effects are too severe to cope with if the medicine is stopped suddenly. Therefore, it is often best to reduce the dose gradually over several months before finally stopping it. Your doctor can advise on dosages, timescale, etc.
Diazepam withdrawal plan
Often, coming off benzodiazepines and Z drugs is just a matter of very slowly reducing them. Sometimes, however, this isn't possible because of the type of tablet you are taking. In this situation a common plan is to switch from whatever benzodiazepine tablet or Z drug you are taking to diazepam. Diazepam is a 'long-acting' benzodiazepine that is commonly used. With diazepam, the dose can be altered very gradually and with greater ease compared to other benzodiazepines.
Your doctor will be able to prescribe the dose of diazepam equivalent to the dose of your particular type of benzodiazepine or Z drug. After this, you can decide with your doctor a plan of how to reduce the dose gradually. You and your doctor will make a plan you are both comfortable with. This can be flexible so you can come off your medication more quickly or more slowly depending on how you are feeling. A common plan is to reduce the dose by a small amount every 1-2 weeks. The amount the dose is reduced at each step may vary, depending on how large a dose you are taking to start with. Also, the last few dose reductions before finally stopping completely may be less than the original dose reductions, and done more gradually.
The gradual reduction of dose keeps any withdrawal symptoms to a minimum.
Occasionally other medication may be prescribed to help you cope with symptoms while you are coming off benzodiazepines. For example, you may be offered antidepressants if depression emerges whilst you are on a withdrawal programme. If anxiety is a problem, sometimes you may be prescribed a tablet called a beta-blocker, such as propranolol.
Some tips that may help
Before coming off a benzodiazepine or a Z drug it may be best to wait until any life crisis has passed and your level of stress is as low as can be.
Consider starting whilst on holiday, when you have less pressure from work, fewer family commitments, less stress, etc.
Consider telling family or friends that you are coming off a benzodiazepine or a Z drug. They may give you encouragement and support.
Consider joining a local self-help group. Advice and support from other people in similar circumstances, or who have come off a benzodiazepine or a Z drug, can be very encouraging.
If you are taking other addictive medicines in addition to benzodiazepines, you may need specialist help for coming off the various medicines. Your doctor will be able to advise you or refer you on to local services which can help.
Other ways of tackling anxiety and sleeping problems
Benzodiazepines and Z drugs are not the long-term answer to anxiety or sleep problems.
If you have anxiety symptoms, there are other ways of tackling your symptoms - for example, learning to relax, or joining an anxiety management group. If anxiety symptoms persist or are severe, your doctor may advise on other treatments such as cognitive behavioural therapy (CBT).
See the separate leaflets called Anxiety, Stress and Tips on How to Avoid It and Cognitive Behavioural Therapy (CBT).
Summary
Most people who have taken a benzodiazepine or a Z drug can successfully come off it. After switching to diazepam (described above), the pace and speed of withdrawal vary greatly from person to person. Go at a pace that is comfortable for you after discussion with your doctor. For many people, the gradual withdrawal and eventual stopping of diazepam take several months. However, some take up to a year to reduce the dose gradually before finally stopping it.
Further reading and references
- Insomnia - zaleplon, zolpidem and zopiclone for the management of insomnia; NICE Technology appraisal guidance, April 2004
- Consensus statement on evidence-based treatment of insomnia, parasomnias and circadian rhythm disorders; British Association for Psychopharmacology (2010)
- Buysse DJ, Germain A, Moul DE, et al; Efficacy of brief behavioral treatment for chronic insomnia in older adults. Arch Intern Med. 2011 May 23;171(10):887-95. Epub 2011 Jan 24.
- Taibi DM, Landis CA, Petry H, et al; A systematic review of valerian as a sleep aid: safe but not effective. Sleep Med Rev. 2007 Jun;11(3):209-30.
- Buysse DJ; Insomnia. JAMA. 2013 Feb 20;309(7):706-16. doi: 10.1001/jama.2013.193.
- British National Formulary (BNF); NICE Evidence Services (UK access only)
- Luik AI, Kyle SD, Espie CA; Digital Cognitive Behavioral Therapy (dCBT) for Insomnia: a State-of-the-Science Review. Curr Sleep Med Rep. 2017;3(2):48-56. doi: 10.1007/s40675-017-0065-4. Epub 2017 May 8.
- Lemoine P, Zisapel N; Prolonged-release formulation of melatonin (Circadin) for the treatment of insomnia. Expert Opin Pharmacother. 2012 Apr;13(6):895-905. doi: 10.1517/14656566.2012.667076. Epub 2012 Mar 19.
- Qaseem A, Kansagara D, Forciea MA, et al; Management of Chronic Insomnia Disorder in Adults: A Clinical Practice Guideline From the American College of Physicians. Ann Intern Med. 2016 Jul 19;165(2):125-33. doi: 10.7326/M15-2175. Epub 2016 May 3.
- Sateia MJ, Buysse DJ, Krystal AD, et al; Clinical Practice Guideline for the Pharmacologic Treatment of Chronic Insomnia in Adults: An American Academy of Sleep Medicine Clinical Practice Guideline. J Clin Sleep Med. 2017 Feb 15;13(2):307-349. doi: 10.5664/jcsm.6470.
- Hale L, Guan S; Screen time and sleep among school-aged children and adolescents: a systematic literature review. Sleep Med Rev. 2015 Jun;21:50-8. doi: 10.1016/j.smrv.2014.07.007. Epub 2014 Aug 12.
- Chang AM, Aeschbach D, Duffy JF, et al; Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness. Proc Natl Acad Sci U S A. 2015 Jan 27;112(4):1232-7. doi: 10.1073/pnas.1418490112. Epub 2014 Dec 22.
- Medicines associated with dependence or withdrawal symptoms: safe prescribing and withdrawal management for adults; NICE guidance (April 2022)
- Insomnia; NICE CKS, April 2024 (UK access only)
- Sleep Diary; The Sleep Charity.
Article history
The information on this page is written and peer reviewed by qualified clinicians.
Next review due: 17 Nov 2027
18 Nov 2022 | Latest version
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