Experiences with

Clonazepam

Clonazepam belongs to a group of medicines called benzodiazepines.

It's used to control seizures or fits due to epilepsy, involuntary muscle spasms, panic disorder and sometimes restless legs syndrome.

It works by increasing the levels of a calming chemical in your brain called gamma-aminobutyric acid (GABA). This can relieve anxiety, stop seizures and fits or relax tense muscles.

Clonazepam is available on prescription only. It comes as tablets and as a liquid that you swallow.

Who can take clonazepam

Most adults aged 18 years old and over can take clonazepam tablets and liquid.

Most children from 1 month old can take it for epilepsy.

Who may not be able to take clonazepam

Clonazepam is not suitable for some people.

To make sure it's safe for you, tell your doctor before starting to take clonazepam if you:

• have ever had an allergic reaction to clonazepam or any other medicine
• have myasthenia gravis, a condition that causes muscle weakness
• have sleep apnoea, a condition that causes breathing problems when you're asleep
• have lung, liver or kidney problems
• have spinal or cerebellar ataxia, where you may become shaky and unsteady and have slurred speech
• have ever had problems with alcohol or drugs
• have recently had a loss or bereavement, depression or thoughts of harming yourself or suicide
• have been diagnosed with a personality disorder
• are trying to get pregnant, are already pregnant or breastfeeding
• are going to be put to sleep (have a general anaesthetic) for an operation or dental treatment

Dosage and strength

Clonazepam tablets come in strengths of 0.5mg, 1mg or 2mg. The liquid contains either 0.5mg or 2mg in 5ml.

If you're taking it for epilepsy or muscle spasms you'll usually start on a low dose and gradually increase it over 2 to 4 weeks until your doctor thinks the dose is right for you.

Your doctor will tell you if you need to take clonazepam in 1 dose or split your dose so you take it up to 3 times each day. Ask a doctor or pharmacist if you're not sure how to take it.

The usual dose for:

• epilepsy in adults – 1mg taken at night as the starting dose, increasing to 4mg to 8mg over 2 to 4 weeks
• epilepsy in children – the dose varies depending on their age. It will be increased gradually over 2 to 4 weeks
• involuntary muscle spasms in adults – 1mg taken at night as the starting dose, increasing to 4mg to 8mg over 2 to 4 weeks
• panic disorder – 1mg to 2mg each day
• restless legs syndrome – 500 micrograms to 2mg each day

If you're older than 65 or have kidney, liver or severe breathing problems, your doctor may recommend a lower dose.

How to take it

Take clonazepam tablets with a drink of water.

You can take the tablets or liquid with or without food.

If you're taking clonazepam as a liquid, the medicine will come with a plastic syringe or spoon to help you measure out the right dose. If you do not have a syringe or spoon, ask your pharmacist for one. Do not use a kitchen teaspoon as it will not measure the right amount.

How long to take it for

How long you take clonazepam for will depend on why you're taking it.

When used for epilepsy, clonazepam is usually prescribed long term.

For other conditions, your doctor will want to regularly review if you still need it.

If you're prescribed clonazepam for more than 4 weeks, your doctor may reduce your dose gradually before stopping it, to prevent withdrawal symptoms.

Do not stop taking clonazepam without talking to a doctor.

If you forget to take your clonazepam, take it as soon as you remember, unless it's nearly time for your next dose. In this case, just leave out the missed dose and take your next dose at the usual time.

Never take 2 doses at the same time. Never take an extra dose to make up for a forgotten one.

If you forget doses often, it may help to set an alarm to remind you. You could also ask a pharmacist for advice on other ways to remember your medicines.

If you take too much

The amount of clonazepam that can lead to an overdose varies from person to person.

If you take too much clonazepam, you may get symptoms including:

• poor coordination or trouble speaking
• feeling sleepy
• a slow or irregular heartbeat
• uncontrolled eye movements
• muscle weakness
• feeling overexcited

• you take more than your prescribed dose of clonazepam

Go to 111.nhs.uk or call 111

If you need 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.

Common side effects

These common side effects of clonazepam happen in more than 1 in 100 people. There are things you can do to help cope with them:

Keep taking the medicine, but speak to a doctor or pharmacist if the advice on how to cope does not help and a side effect is still bothering you or does not go away.

Serious side effects

It happens rarely, but some people can have serious side effects when taking clonazepam.

Call a doctor or call 111 now if:

• the whites of your eyes turn yellow, or your skin turns yellow although this may be less obvious on brown or black skin – this could be a sign of liver problems
• you see or hear things that are not there (hallucinations) or think things that are not true (delusions)
• you have problems with your coordination or controlling your movements
• you have swollen ankles, a racing heartbeat, a cough and feel tired – this could be a sign of heart problems
• you bruise easily, feel tired, have nosebleeds and have breathlessness – this could be a sign of blood problems
• you notice mood changes such as talking more than usual or feeling overexcited, restless, irritable or aggressive – these side effects are more likely in children or if you're over 65

Make an appointment to see your doctor if you have difficulty remembering things (amnesia).

• you have difficulty breathing or changes to your breathing

Find your nearest A&E

In rare cases, clonazepam may cause a serious allergic reaction (anaphylaxis).

Clonazepam can cause withdrawal symptoms if you take it for a long time.

If you're prescribed clonazepam for more than 4 weeks, your dose may be reduced gradually when you stop taking it to prevent withdrawal symptoms.

Other side effects

These are not all the side effects of clonazepam. For a full list, see the leaflet inside your medicine packet.

Clonazepam and pregnancy

Clonazepam can be taken during pregnancy, particularly if you need it to control your epilepsy.

Speak to your doctor if you take clonazepam and are pregnant or are planning to get pregnant. They'll help you weigh up the risks and benefits of taking clonazepam and make sure that treatment is right for you.

Taking clonazepam in late pregnancy might affect your baby, making them more drowsy and sleepy. The baby will be monitored for these effects after they're born.

Clonazepam and breastfeeding

If your doctor, health visitor or midwife says your baby is healthy, you can usually take clonazepam if you are breastfeeding.

There is not much information about taking clonazepam while breastfeeding, but it is thought that it passes into breast milk in very small amounts. It does not usually cause side effects in breastfed babies.

If you take clonazepam for a long time, in high doses, or with other medicines, your baby may be more likely to get side effects, although this is still rare. This can make your baby drowsy or tired and can make it difficult for them to feed.

Talk to your health visitor, midwife, doctor or pharmacist as soon as possible if you have any concerns, or if your baby:

• is not feeding as well as usual
• seems unusually sleepy
• has unusual breathing

It's important not to share a bed with your baby while you're taking clonazepam.

Clonazepam and fertility

There's no evidence that clonazepam will affect fertility in either men or women.

If you're trying to get pregnant, or you're having problems getting pregnant while on clonazepam, speak to a doctor.

Cautions with other medicines

Some medicines affect the way clonazepam works and increase the chance of you having side effects.

Before you start taking clonazepam, tell a doctor if you're taking any of these medicines:

• anticonvulsants, used to treat epilepsy
• antipsychotics or antidepressants, used to treat mental health problems and depression
• hypnotics, used to treat anxiety or sleep problems
• medicines used to treat muscle spasms, such as baclofen or tizanidine
• medicines used to lower blood pressure, including ACE inhibitors such as enalapril or lisinopril, calcium channel blockers such as amlodipine or felodipine, or diuretics such as indapamide or bendroflumethiazide
• drowsy (sedating) antihistamines, such as chlorphenamine or promethazine
• strong painkillers such as codeine, methadone, morphine, oxycodone, pethidine or tramadol
• cimetidine, a medicine for stomach problems and heartburn
• rifampicin, a medicine to treat bacterial infections
• antifungal medicines such as fluconazole

Mixing clonazepam with herbal remedies or supplements

Do not take herbal remedies for anxiety or insomnia, such as valerian or passionflower, with clonazepam. They can increase the drowsy effects of clonazepam and may also have other side effects.

There's not enough information to say that other complementary medicines, herbal remedies and supplements are safe to take with clonazepam. They're not tested in the same way as pharmacy and prescription medicines. They're generally not tested for the effect they have on other medicines.

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