Benzodiazepines act as a sedative – slowing down the body’s functions – and are used for both sleeping problems and anxiety.
They work by increasing the effect of a brain chemical called GABA (gamma amino butyric acid). GABA reduces brain activity in the areas of the brain responsible for:
- rational thought
- essential functions, such as breathing
The main effects of benzodiazepines are:
- reduced anxiety
- muscle relaxation
Benzodiazepines are very effective in the short term but they may stop working if you take them continuously for more than a few months. This is because your brain adjusts to their effect, and may be hypersensitive to natural brain chemicals when they are stopped.
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 and how should benzodiazepines be used?
Benzodiazepines should only be used to treat severe anxiety or severe insomnia that is having a significant impact on your day-to-day life.
There are some situations when their use may not be appropriate. After a bereavement, for example, tranquillisers may numb your emotions and prevent you from grieving properly. But if you are unable to sleep because of grief and anxiety, a sleeping pill may help you to relax and start to recover.
Benzodiazepines are likely to be most effective if you take them as a one-off dose for one occasion, and not as continuous treatment.
The usual advice is that they should not be taken for longer than four weeks, and should not be taken every day. However, depending on individual circumstances, some doctors may prescribe them at low doses for long periods and this does not always cause a problem – this could be the best treatment for some people.
I can see why it's so addictive, it makes you feel so good – but you keep needing more of it to get the same effect.
Who shouldn’t take benzodiazepines?
It is important that your doctor knows about any medical conditions you have and any treatment you are already receiving before they prescribe you a benzodiazepine. They can then decide whether you should take them and, if so, which one would be most suitable for you.
You should not take benzodiazepines if you have:
- severe lung disease or breathing problems
- sleep apnoea (breathing problems during sleep)
- severe liver or kidney disease
You should use these drugs with caution if you have:
You should be given a reduced dose if you have:
- liver or kidney problems
- porphyria (a rare, inherited illness)
Benzodiazepines should not be used as the only treatment for depression.
- Children – benzodiazepines are not suitable for children, except in rare cases of acute anxiety or insomnia caused by fear or sleepwalking, when diazepam may be used
- Older people should be given a lower dose than the standard adult dose
Can I take them during pregnancy and breastfeeding?
Benzodiazepines should be avoided if possible during pregnancy. There is a small risk of physical problems in the developing baby, such as:
- cleft palate
- urinary tract abnormalities
- heart abnormalities
- stomach abnormalities
- dyslexia (difficulty reading and writing)
- dyspraxia (problems with co-ordination and movement)
- attention deficit hyperactivity disorder (ADHD)
If taken at the end of pregnancy, benzodiazepines can cause the following problems in newborn babies:
- floppy muscles
- breathing problems
- low body temperature
- withdrawal symptoms including abnormal sleeping patterns, high-pitched crying, tremor (shaking), vomiting and diarrhoea
You should not breastfeed your baby while taking benzodiazepines because the drugs are present in breast milk, and may build up in the baby’s body and cause side effects.
Can I take benzodiazepines with other medication?
If you are taking any other medicines (on prescription, over-the-counter, or from an alternative health practitioner), tell your doctor or the pharmacist. Combining other medication with benzodiazepines can change the effects of the drugs or cause additional side effects.
Benzodiazepines are often used in combination with other psychiatric drugs:
- Benzodiazepines and antidepressants – if you are prescribed antidepressants, some doctors may suggest that you also take a benzodiazepine at first. This is because benzodiazepines work quickly, while antidepressants may take a few weeks to have an effect. Once the antidepressants start to have an effect, you can stop the benzodiazepine and continue with the antidepressant.
- Benzodiazepines and antipsychotics – sometimes used together to treat schizophrenia or similar conditions. You may be given them short-term to calm you down quickly if you are very agitated or over-excited, or having a severe mental health crisis (especially if you are in hospital).
For specific drug interactions, see the Sleeping Pills and Minor Tranquillisers A-Z.
Note: drinking alcohol increases the sedative effect of benzodiazepines. Ask your doctor or pharmacist whether it’s safe to drink alcohol while you’re taking these drugs.
This information was published in August 2016. We will revise it in 2018.