Sleeping pills and minor tranquillisers
Explains what sleeping pills and minor tranquillisers are used for, how the medication works, possible side effects and information about withdrawal.
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What are benzodiazepines?
Benzodiazepines are a type of sedative medication. This means they slow down the body and brain’s functions. They can be used to help with anxiety and insomnia (difficult getting to sleep or staying asleep).
This page covers:
How do benzodiazepines work?
Your body has a natural chemical called gamma aminobutyric acid (GABA). This chemical reduces the activity in the areas of the brain responsible for:
- reasoning
- memory
- emotions
- essential functions, such as breathing.
Benzodiazepine drugs increase the effects of GABA on your brain and body. This means these drugs can:
- make you feel relaxed and sleepy (sedation)
- reduce your anxiety
- relax your muscles.
The term benzodiazepine is the name for a chemical structure that affects your brain and body in certain ways.
All benzodiazepine drugs contain this chemical structure. This means they will all have similar effects on your brain and body.
During one particularly bad time I was prescribed diazepam alongside my antidepressants. It really helped me at the time. However, as my body got used to the drug I needed more of it to get the same effect.
When might I be prescribed benzodiazepines?
Benzodiazepines may be prescribed to treat severe anxiety or severe insomnia, when either is having a significant impact on your daily life. In some cases, doctors may prescribe the benzodiazepine clonazepam to treat panic disorder.
There are some situations when benzodiazepines may not be the most effective treatment. For example, if you are experiencing bereavement, these drugs may numb your emotions and stop you grieving properly.
But you may also be unable to sleep because of grief and anxiety. In this case, taking these drugs for a short time may help you relax and start to recover.
Our page on what you may need to know before taking medication has a list of things to ask your doctor before you begin taking any medication. This can help you to decide whether benzodiazepines are right for you.
How often to take benzodiazepines
Most benzodiazepines are likely to be more effective if you take them as a one-off dose. They can also be effective as a short-term treatment for a few weeks. Doctors will usually advise that you should:
- avoid taking them every day
- take them for no longer than four weeks.
These drugs are less likely to keep working if you take them continuously for more than a few weeks. This is because your brain can get used to their effects. It can also mean that when you stop taking the drugs, your brain becomes very sensitive to natural brain chemicals.
In some cases, doctors may prescribe certain benzodiazepines at low doses for longer periods. This does not always cause problems, and it could be the best treatment for some people.
Who should avoid taking benzodiazepines?
Your doctor will not normally prescribe you benzodiazepines if you have:
- severe lung disease or breathing problems
- sleep apnoea (breathing problems during sleep)
- severe liver or kidney disease
- severe and uncontrolled myasthenia gravis (a neuromuscular condition).
Your doctor may be cautious about offering you benzodiazepines if you have:
- chest and lung problems
- muscle weakness, such as myasthenia gravis
- a history of alcohol or drug abuse
- a diagnosis of personality disorder.
Your doctor should prescribe a reduced dose of benzodiazepines if you have:
- liver or kidney problems
- porphyria (a rare, inherited illness)
Whether you are prescribed benzodiazepines may also depend on your age:
- Benzodiazepines are not suitable for children. This is except for rare cases of anxiety or insomnia caused by fear or sleepwalking, when diazepam may be prescribed.
- Older people should be given a lower dose than the standard adult dose.
Benzodiazepines during pregnancy and breastfeeding
There is not enough research to know exactly how common problems are with taking benzodiazepines while you are pregnant. Some people have reported the following problems with their baby after taking benzodiazepines during pregnancy:
- cleft palate
- urinary tract abnormalities
- heart abnormalities
- stomach abnormalities
- dyslexia (difficulty reading and writing)
- dyspraxia (problems with co-ordination and movement)
- autism
- attention deficit hyperactivity disorder (ADHD).
Some people have also reported the following problems in their baby after taking benzodiazepines towards the end of their pregnancy:
- drowsiness
- floppy muscles
- breathing problems
- low body temperature
- withdrawal symptoms including abnormal sleeping patterns, high-pitched crying, tremor (shaking), vomiting and diarrhoea.
If you take certain benzodiazepines while breastfeeding, the medication may be present in your breast milk. In some cases, this can build up in your baby’s body and cause side effects.
If you are breastfeeding, pregnant or planning to become pregnant, you can ask your doctor about the risks of taking your specific medication.
Taking benzodiazepines with other medication
Combining benzodiazepines with other medications can change the effects of the drugs. This may include reducing the positive effects of either drugs. Or it may lead to negative side effects.
Sometimes doctors may prescribe you benzodiazepines at the same time as other drugs. For example, they may prescribe benzodiazepines with antidepressants or antipsychotics.
The benzodiazepines may be to help you cope with anxiety while you wait for the other medication to begin working. But there may also be negative effects from this, if the drugs interact in a way that causes unwanted side effects.
You can find out about known medication interactions for individual benzodiazepines from the British National Formulary (BNF) A-Z list of drug interactions.
You can also speak to your doctor or pharmacist if you are concerned about taking any other medication with benzodiazepines. This includes prescribed medication, over-the-counter drugs and herbal remedies.
Benzodiazepines with alcohol or recreational drugs
Drinking alcohol can increase the sedative effect of benzodiazepines. This can cause some dangerous side effects. You can speak to your doctor or pharmacist about whether it’s safe to drink alcohol with a specific benzodiazepine.
Some recreational drugs can also interact with benzodiazepines in a dangerous way. See our page on recreational drugs and medication for more information on how recreational drugs can interact with medications.
This information was published in April 2021. We will revise it in 2024.
References and bibliography available on request.
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