Clonazepam is the generic name (non-brand name) of the seizure medicine Klonopin used in the United States, Canada, the UK and some other countries.

Generic clonazepam is manufactured in the United States by several different companies including TEVA pharmaceuticals, Watson Labs and Caraco Pharmaceutical Laboratories, Ltd. The name or appearance may differ in other countries. Clonazepam is available in tablet form in 0.5 mg,1.0 mg and 2.0 mg prescription strength.

See package insert.

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Updated: 16/10/2023

Brand Name(s)

Klonopin

Used to Treat

Lennox-Gastaut Syndrome
Absence Seizures
Myoclonic Seizures

Forms

Tablet
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Klonopin 0.5mg

0.5 mg: round, orange-colored tablet marked with K

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Klonopin 1mg

1 mg: round, blue tablet marked with K

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Klonopin 2mg

2 mg: round, white tablet marked with K

Wafers (orally disintegrating tablets) (not pictured)
White, round tablets packaged in a blister pack, at various doses:

0.125 mg (marked 1/8)
0.25 mg (marked 1/4)
0.5 mg (marked 1/2)
1 mg (marked 1)
2 mg (marked 2)

Package Insert

Frequently Asked Questions

    How to take and store Clonazepam?

    Tablets

    • Regular Klonopin tablets should be swallowed whole, with a little water. Do not bite them.

    Klonopin Wafers

    • Klonopin wafers will dissolve rapidly in saliva, so water is not necessary (but drinking some is OK). Using dry hands, place the wafer in the mouth immediately after peeling back the foil from the blister pack.

    Taking Klonopin

    • It's OK to take Klonopin either with food or without food. It is recommended that if the doses are not equally divided during the day, the largest dose should be taken at bedtime.

    Be careful if the doctor writes a new prescription using a different kind of pill. For example, if you've been using 1-mg tablets and the new prescription is for 2-mg tablets, be careful to use the correct number. Don't automatically continue to use the same number of pills as before.

    Store all types of Klonopin at room temperature.

    What if I forget?

    A forgotten dose should be taken right away. If it is almost time for the next one, just use one dose, not a double dose, and call the doctor's office for more advice.

    Do your best to follow the doctor's directions. If you forget doses often, it may be a good idea to get a special pillbox or watch with an alarm to remind you.

    Taking the right amount of seizure medicine on time every single day is the most important step in preventing seizures!

    How well does the Clonazepam work?

    Clonazepam is usually used as an "add-on" medication for people who continue to have seizures while taking other seizure medicines, or sometimes as a medication of last resort after most others have failed. It sometimes loses its efficacy after a while.

    Clonazepam has been available in the United States since 1975, so doctors have plenty of experience with its use, but few large, well-controlled studies of its effectiveness have been performed. It has been shown to work for many different seizure types.

    It can be used to treat absence seizures, often in combination with Depakote (valproate). Clonazepam is particularly effective against some types of myoclonic seizures such as juvenile myoclonic epilepsy and progressive myoclonic epilepsy. Again, it is often used in combination with Depakote.

    Clonazepam is useful for seizures brought on by flashing lights (photosensitivity).

    Children with Lennox-Gastaut syndrome also frequently benefit from its use, though not all studies have found it helpful for long-term treatment.

    Clonazepam is usually regarded as less effective against partial seizures than carbamazepine (Tegretol or Carbatrol) or phenytoin (Dilantin, Phenytek).

    Factors influencing the decision about whether to add clonazepam to a regimen of seizure medicines that are not fully controlling a person's seizures may include potential interactions, side effects, and the mechanisms of action of the various medications. No single combination is perfect for everyone. Sometimes, a series of combinations must be tried before finding what is best for the individual.

    Here is a link to a summary of one clinical trial of clonazepam (Klonopin):

    Mikkelsen B, Birket-Smith E, Bradt S, et al. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=817696&dopt=Abstract Clonazepam in the treatment of epilepsy. A controlled clinical trial in simple absences, bilateral massive epileptic myoclonus, and atonic seizures Arch Neurol. 1976;33(5):322-325. PMID: 817696

    This small study reported very good results when clonazepam (Klonopin) was used as add-on therapy. Most patients experienced side effects, but they were usually tolerable.

    What are the most common side effects of Clonazepam?

    Clonazepam belongs to a class of medications called benzodiazepines. Benzodiazepines are tranquilizers (sedatives) that prevent or stop seizures by slowing down the central nervous system. This makes abnormal electrical activity less likely. As a result, common symptoms include:

    • tiredness
    • dizziness
    • unsteadiness
    • impaired attention and memory
    • irritability
    • hyperactivity (in children)
    • drooling (in children)
    • depression (usually in adults)
    • nausea
    • loss of appetite

    Scientific studies show that about half of people treated for seizures with clonazepam experience drowsiness and about 30% have problems with coordination. In some cases, these problems diminish with time.

    About 25% have behavior problems such as hyperactivity in children. Problems with thinking and behavior are greater with clonazepam than with seizure medicines like Tegretol, Dilantin, and Depakote.

    If these problems do not go away within several days, or are really bothersome, call the doctor. Sometimes the doctor can help with these side effects by changing the prescription:

    • reducing the overall amount of clonazepam
    • changing the amount taken at certain times, such as taking a greater proportion of the clonazepam at bedtime to reduce daytime sleepiness
    • prescribing smaller doses, to be taken more often

    No one should stop taking clonazepam or change the amount they take or when they take it without their doctor's guidance.

    People who have just started taking clonazepam (or who have just started taking a larger amount) should be careful during activities that might be dangerous, until they know whether they are having any side effects.

    What are the most serious side effects of Clonazepam?

    Most people who take clonazepam have no side effects or mild side effects that go away with no lasting harm. But a few people have serious reactions. Here's a list of symptoms that may be the start of one of these problems. If you notice any of these symptoms, call the doctor right away:

    • An allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, face, or tongue; or hives)
    • Sores in the mouth or throat (could mean a blood problem)
    • Yellowing of the skin or eyes
    • Rash
    • Hallucinations, severe confusion, or changes in vision

    One of the great dangers in using medications like clonazepam is the tendency to increase the dose as tolerance develops. To a certain extent, dosage increases may be necessary, but adverse effects may be increased more than seizure control. If the dosage is increased gradually over a long period, subtle changes in personality (such as irritability, depression, or decreased motivation) or problems such as impaired memory may go unnoticed or be considered natural for that person.

    High doses sometimes are prescribed, especially for those with developmental disabilities. Problems with thinking and behavior may be the result. If the dose has been increased gradually over many months or years, it can be hard to separate the effects of the clonazepam (or other benzodiazepines) from the effects of other medications, seizures, and other neurological and psychological disorders.

    An important concern when people with epilepsy take clonazepam or other benzodiazepines is the risk that seizures will become more frequent or more severe if the medicine is reduced or stopped. The longer the person has been taking clonazepam and the higher the dosage, the greater the tolerance and therefore the higher the risk of worsening seizure control. Even small, gradual dose reductions can temporarily increase seizure activity, but the long-term decrease in effects like drowsiness and depression often makes the change worthwhile.

    Also, sometimes clonazepam makes people feel sleepy or uncoordinated. If you've just started taking clonazepam or have just had your dosage increased, especially if you tend to be sensitive to medications, be careful when doing things that could be dangerous until you know how it will affect you.

    Finally, clonazepam and other benzodiazepines are the medicines that are most likely to cause psychological dependence. When someone takes a benzodiazepine at a certain dosage for more than 2 to 4 weeks, the body (or specifically, the brain's receptors for the neurotransmitter GABA) becomes accustomed to it. Then if a dose is missed or reduced, a withdrawal process starts and the person experiences:

    • anxiety
    • increased heart rate
    • tremor
    • general unwell feeling

    Taking another pill relieves all of these symptoms, confirming the person's belief that he or she "needs" the medication. This is a very dangerous cycle, since long-term use can cause long-lasting changes in the brain's GABA receptors that lead to significant problems such as impaired thinking, decreased motivation, and depression. In this setting, rapid dose reduction can cause severe symptoms of anxiety, insomnia, and illness, as well as seizures. In many of these cases, very gradual reduction of the benzodiazepine (often over many months or years) can lead to a dramatic improvement in attention, concentration, memory, and mood without worsening the seizures, insomnia, or anxiety for which the medication was originally prescribed.

    On July 10, 2008, an advisory panel was convened by the Food and Drug Administration (FDA) to review data that the FDA had previously collected from drug studies showing an association between many of the antiepileptic drugs (AEDs) and suicidal ideation and behavior, which together are called suicidality. According to the FDA’s Alert, among the patients with epilepsy in these drug studies, 1 out of 1000 people taking the placebo (inactive substance) showed suicidality compared to approximately 3.5 out of 1000 people who took an AED. The FDA advisory panel voted to accept the FDA's data at its meeting on July 10.

    Taking antiepileptic medicines may increase the risk of having suicidal thoughts or actions;

    • Do not make any changes to the medication regimen without first talking with the responsible healthcare professional;
    • Pay close attention to any day-to-day changes in mood, behavior and actions. These changes can happen very quickly so it is important to be mindful of any sudden differences.

    Be aware of common warning signs that might be a signal for risk of suicide. Some of these are:

    • Talking or thinking about wanting to hurt yourself or end your life
    • Withdrawing from friends and family
    • Becoming depressed or having your depression get worse
    • Becoming preoccupied with death and dying
    • Giving away prized possessions

    We again urge patients and families to contact their doctor before stopping an epilepsy medication because this may possibly lead to seizures and worsening of mood.

    What are the effects of Clonazepam on Children?

    In children, drowsiness or hyperactivity can occur if clonazepam is started too quickly. Some children are very sensitive to these side effects, which can occur even if the clonazepam is introduced at very low doses. Children up to 10 years of age or up to 30 kilograms (about 65 pounds) of body weight generally start by taking no more than 0.01 to 0.02 mg per kg each day (a total of 0.25 to 0.75 mg per day for a child weighing 65 pounds or more). This amount is given in two or three doses per day.

    Dosage should then increase by no more than 0.01 to 0.02 mg/kg every third day. The final daily maintenance dose is usually 0.1 to 0.2 mg/kg of body weight (depending on total weight and age).

    If high doses are prescribed for children, especially those with developmental disabilities, problems with thinking and behavior may be the result. If the dose has been increased gradually over many months or years, it can be hard to separate the effects of the clonazepam (or other benzodiazepines) from the effects of other medications, seizures, and other neurological and psychological disorders.

    What are the dose ranges for Clonazepam?

    Follow your doctor's directions.Call if you have any questions. If you are an adult, most doctors will tell you to start by taking no more than 0.5 to 1.5 milligrams (mg) of clonazepam per day, which may be taken all at once or divided into two or three doses. Often the medicine is started at 0.5 mg, taken at bedtime to promote sleep and avoid daytime drowsiness. To get better control of your seizures, the doctor may increase the dosage by 0.5 to 1 mg every 3 to 7 days. The maximum daily dose recommended is 10 mg. In a survey of epilepsy specialists, most recommended no more than 4 mg per day and usually prescribed no more than 2 mg per day.

    If your seizures nearly always occur during sleep or first thing in the morning, the doctor may tell you to take all the tablets at one time, usually at bedtime. If daytime seizures occur, you may be told to take some clonazepam two or three times a day. Ask the doctor what to do if you forget to take a dose.

    Children up to 10 years of age or up to 30 kilograms (about 65 pounds) of body weight need to start at a very low dose. They generally start by taking no more than 0.01 to 0.02 mg per kg each day (a total of 0.25 to 0.75 mg per day for a child weighing 65 pounds or more). This amount would be given in two or three doses.

    The dosage for children should then increase by no more than 0.01 to 0.02 mg/kg every third day until a daily maintenance dose of 0.1 to 0.2 mg/kg of body weight (depending on total weight and age) has been reached.

    Read the package insert of Clonazepam

    In the United States, companies that manufacture medicines are required to publish certain kinds of information about each product. This document is commonly known as a “package insert” because it is usually included with each package of the medicine.

    You can also read these documents (also called "prescribing information") online. The U.S. package insert for Klonopin (clonazepam) is found at:

       http://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?id=9729

    Some of the information may differ in other countries.

    The summary of package characteristics can be obtained in any European language from:

        http://www.ema.europa.eu/ema/index.jsp?curl=pages/includes/medicines/medicines_landing_page.jsp.

    To learn how to read and understand a package insert, see "How to read a package insert."

    Read About Clonazepam studies

    If you visit PubMed (http://www.ncbi.nlm.nih.gov/pubmed/), a service of the National Library of Medicine, you can read summaries of studies that have tested the effectiveness of clonazepam, as well as other reports about this medication.

    Here is a link to one article related to clonazepam:

    Mikkelsen B, Birket-Smith E, Bradt S, et al. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=817696&dopt=Abstract>Clonazepam in the treatment of epilepsy. A controlled clinical trial in simple absences, bilateral massive epileptic myoclonus, and atonic seizures. Arch Neurol. 1976;33(5):322-325. PMID: 817696

    This small study reported very good results when clonazepam (Klonopin) was used as add-on therapy. Most patients experienced side effects, but they were usually tolerable.

    Primary-Generalized-Epilepsy

    Primary Generalized Epilepsy

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