What clonazepam is for
Clonazepam is a type of medicine called a benzodiazepine. It's used to used to treat seizures caused by epilepsy.
It's also sometimes used for panic disorder when other medicines have not worked.
It works by calming activity in your brain and nerves. For epilepsy, this helps to reduce the number of seizures you have and can make seizures less serious.
How to take clonazepam
How much clonazepam you need to take depends on your age and why you're taking it.
For epilepsy, you usually take it once a day, in the evening. But some people may need to take it in divided doses.
Your doctor will usually prescribe a low dose when you first start taking clonazepam and increase it if needed.
When taking clonazepam:
- swallow tablets whole with water
- use the syringe or spoon that comes with the liquid medicine to help you measure the right dose
- you can take it with or without food
Always check the packet or leaflet that comes with your medicine. Ask a pharmacist or doctor for advice if you're not sure how to take it or have any problems taking it.
If you miss a dose of clonazepam
If you forget to take a dose, skip the missed dose and take your next dose at the usual time.
Do not take 2 doses to make up for a missed dose.
If you take too much clonazepam
Taking an extra dose of clonazepam can be dangerous.
Urgent advice: Call NHS 111 if:
- you've taken more than your prescribed dose of clonazepam
If you're told to go to A&E, do not drive. Ask someone to drive you or call 999 and ask for an ambulance.
Bring the clonazepam packet or leaflet inside it, any remaining medicine, and any other medicines you take.
How to stop taking clonazepam
Do not stop taking clonazepam unless your doctor tells you to. Stopping suddenly can cause withdrawal symptoms and may make your epilepsy symptoms worse.
If you need to stop taking clonazepam, your doctor will usually reduce your dose slowly over several weeks or months.
It's possible to become addicted to clonazepam. Your doctor will prescribe the lowest dose you need to help your symptoms.
Talk to your doctor if you're worried about addiction or stopping taking clonazepam.
Always follow your doctor's advice.
Side effects of clonazepam
Like all medicines, clonazepam can cause side effects, although not everyone gets them.
Possible side effects of clonazepam include:
- feeling sleepy, tired, dizzy or less alert
- headaches
- feeling restless or agitated
- feeling low or depressed
- shaking
- muscle weakness
If you feel sleepy, dizzy or less alert after taking clonazepam, do not drive, ride a bike or use machinery until you no longer have these symptoms.
Non-urgent advice: Speak to a pharmacist or doctor if:
- you have any side effects that bother you or do not go away
They may be able to give you advice about how you can reduce the side effects. Keep taking your medicine unless you're advised to stop.
Find a pharmacySerious side effects
Clonazepam can sometimes cause serious side effects, although most of them are rare.
Possible serious side effects of clonazepam include:
- an allergic reaction (anaphylaxis) – causing symptoms such as a swollen throat or tongue, a raised, itchy rash or difficulty breathing
- difficulty breathing – causing slower, more shallow breaths or very slow breathing
- liver problems – causing symptoms such as darker pee than normal, pale poo, and yellowing of the whites of your eyes or skin (yellowed skin may be more difficult to see on black or brown skin)
- mental health problems – such as hearing or seeing things that are not there (hallucinations), believing things that are not true (delusions), feeling low or depressed, or having thoughts of suicide or harming yourself
Immediate action required: Call 999 if:
- you're taking clonazepam and have severe difficulty breathing or think you might be having anaphylaxis
If you're having thoughts of harming yourself, or think you're having any other serious side effect, call NHS 111.
More about side effects
These are not all the side effects of clonazepam.
For a full list, see the leaflet that comes with your medicine or search for your medicine leaflet on the electronic medicines compendium website.
You can report any side effects you get on the Yellow Card website
Who can and cannot take clonazepam
Most adults and children can take clonazepam.
But it's not suitable for everyone. For example, it may not be suitable if:
- you've had an allergic reaction or other serious side effect from clonazepam or another benzodiazepine
- you have sleep apnoea or breathing problems
- you have muscle weakness or a condition that causes it, such as myasthenia gravis
- you have kidney or liver problems
- you've been addicted to alcohol, drugs or prescription medicine before, especially opioids
- you have ever had depression or thoughts of harming yourself
- you have porphyria, a rare blood condition
Before taking clonazepam, tell your doctor if you have any medical conditions.
Breastfeeding and clonazepam
Tell your doctor if you're breastfeeding.
Clonazepam is sometimes used while breastfeeding, but only if the benefits outweigh the risks.
It's possible for breastfed babies to get side effects if you're taking clonazepam, such as being sleepier or breathing more slowly than usual. Speak to a healthcare professional or call NHS 111 if you have any concerns about your baby.
Do not sleep in the same bed (co-sleep) with your baby if you've taken clonazepam or any other medicine that makes you sleepy or drowsy, as it can increase the risk of sudden infant death syndrome (SIDS).
Pregnancy and clonazepam
Tell your doctor if you're pregnant, or get pregnant while taking clonazepam.
Clonazepam may be used during pregnancy. Your doctor will talk to you about the risks and benefits of taking it while you're pregnant.
You may also be advised to give birth in hospital so you and your baby can be closely monitored after you've given birth.
Taking clonazepam with other medicines, food and drink
There are some medicines, remedies and supplements that may not mix well with clonazepam.
This includes:
- other medicines for epilepsy, such as carbamazepine, lamotrigine and sodium valproate
- medicines for moderate or severe pain, including opioid painkillers like morphine, codeine or oxycodone
- medicines for sleep or anxiety problems
- some medicines for mental health problems, such as antidepressants or antipsychotics
- cimetidine, used to lower the amount of acid in your stomach
- rifampicin, an antibiotic
Before taking clonazepam, tell your doctor if you're taking any other medicines, herbal remedies, vitamins or supplements.
Food, drink and alcohol with clonazepam
Do not drink alcohol while taking clonazepam. Alcohol can increase the effects of the medicine, which can cause breathing problems and make it very difficult to wake up.
Otherwise, you can eat and drink as normal while taking clonazepam.
Find out more about your medicine
To find out more about your medicine, you can:
- check the leaflet that comes with it
- search for your medicine leaflet on the electronic medicines compendium website
- find out about the law on drugs and driving (GOV.UK)
- speak to a pharmacist or a doctor for advice