Sleeping pills and minor tranquillisers

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Side effects of benzodiazepines

This page lists many of the known side effects of benzodiazepines. The effects may be slightly different between individual drugs. And everyone reacts to medication differently, so you may or may not experience these effects.

The most common side effects of benzodiazepines include:

• drowsiness
• light-headedness
• confusion
• unsteadiness (especially in older people, who may fall and experience injuries)
• dizziness
• slurred speech
• muscle weakness
• memory problems
• constipation
• nausea (feeling sick)
• dry mouth
• blurred vision.

Some less common side effects of benzodiazepines include:

• headaches
• low blood pressure
• increased saliva production
• digestive disturbances
• rashes
• sight problems, such as double vision
• tremors (shaking)
• changes in sexual desire
• incontinence (loss of bladder control)
• difficulty urinating.

Some rare side effects of benzodiazepines include:

• blood disorders
• jaundice (yellow skin)
• gynecomastia (breast development in people assigned male at birth).

Memory problems with benzodiazepines

For some people, benzodiazepines can cause problems with memory. These problems are likely to be with retaining new memories while you take the medication. It is unlikely that they will cause you to forget old memories.

Your doctor may not prescribe benzodiazepines to help you sleep unless you are sure that you can sleep for a full night without being disturbed. This usually means sleeping for around seven to eight hours. This is because of how your mind works to retains memories while you are sleeping. Some benzodiazepines can disturb this process.

Paradoxical effects of benzodiazepines

Benzodiazepines sometimes cause effects which are the opposite of the medication is meant to do. You may hear these referred to as 'paradoxical' effects. They include:

• aggressive behaviour
• agitation
• anxiety
• delusions (strongly held beliefs that other people don't share)
• depersonalisation (feeling detached from your surroundings)
• depression
• derealisation (feeling out of touch with reality)
• hallucinations
• inappropriate behaviour, with loss of normal inhibitions
• irritability
• nightmares
• personality changes
• psychosis
• rages
• restlessness
• suicidal thoughts or behaviour.

These effects may happen with any benzodiazepine. They are more common in children and older people, and with short-acting benzodiazepines.

Effects of long-term benzodiazepine use

If you take benzodiazepines for more than two to four weeks, you may experience symptoms like:

• difficulty concentrating
• feeling dulled and slow
• feeling isolated and unreal
• feeling cut off from your emotions
• feeling irritable and impatient
• loss of confidence
• weight problems
• memory problems.

You may also experience withdrawal symptoms while you are still taking the drugs. Or you may need to take a higher dose to continue feeling the positive effects of the medication.

Reporting side effects of benzodiazepines

If you experience side effects from any medication, you can report them to the Yellow Card scheme, which is run by the Medicines and Healthcare Products Regulatory Agency (MHRA). This is the organisation which regulates the use of medications in the UK.

You can report any side effect you experience, including any that are may already be known. You can also ask a healthcare professional to report any side effects for you.

Recently I had a tough time and would love to go back on diazepam to help me through it, but personally wouldn't trust myself on it as I have a three-year-old son and I'm a single parent. I'm not sure I'd wake in the night or be able to function in the day.

This information was published in April 2021. We will revise it in 2024.

References and bibliography available on request.

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