What is clonazepam?

Clonazepam is in a group of drugs called benzodiazepines (ben-zoe-dye-AZE-eh-peens). Clonazepam affects chemicals in the brain that may become unbalanced and cause anxiety.

Clonazepam is used to treat seizure disorders or panic disorder.

Clonazepam may also be used for other purposes not listed in this medication guide.

Precautions

Do not use this medication if you have severe liver disease, or if you are allergic to clonazepam or to other benzodiazepines, such as alprazolam (Xanax), chlordiazepoxide (Librium), clorazepate (Tranxene), lorazepam (Ativan), or oxazepam (Serax).

Before taking clonazepam, tell your doctor if you are allergic to any drugs, or if you have:

  • kidney or liver disease;
  • glaucoma;
  • asthma, emphysema, bronchitis, chronic obstructive pulmonary disorder (COPD), or other breathing problems;
  • a history of depression or suicidal thoughts or behavior; or
  • a history of drug or alcohol addiction.

If you have any of these conditions, you may need a dose adjustment or special tests to safely take this medication.

FDA pregnancy category D. Clonazepam may cause harm to an unborn baby, and may cause breathing or feeding problems in a newborn. But having a seizure during pregnancy could harm both the mother and the baby. Do not start taking clonazepam during pregnancy without telling your doctor you are pregnant.

If you become pregnant while taking clonazepam for seizures, do not stop taking clonazepam without your doctor’s advice. Seizure control is very important during pregnancy and the benefits of preventing seizures may outweigh any risks posed by taking clonazepam.

Clonazepam may pass into breast milk and could harm a nursing baby. Do not breast-feed a baby while taking this medication.

The sedative effects of clonazepam may last longer in older adults. Accidental falls are common in elderly patients who take benzodiazepines. Use caution to avoid falling or accidental injury while you are taking clonazepam.

Clonazepam may be habit-forming and should be used only by the person it was prescribed for. Clonazepam should never be shared with another person, especially someone who has a history of drug abuse or addiction. Keep the medication in a secure place where others cannot get to it.

Do not drink alcohol while taking clonazepam. This medication can increase the effects of alcohol.

Clonazepam can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.

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Instructions

Seek emergency medical attention if you think you have used too much of this medicine.

Overdose symptoms may include extreme drowsiness, confusion, muscle weakness, and fainting.

Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at your next regularly scheduled time. Do not take extra medicine to make up the missed dose.

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Side Effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have any of these serious side effects:

  • confusion, hallucinations, unusual thoughts or behavior;
  • hyperactivity, agitation, hostility;
  • unusual or involuntary eye movements;
  • weak or shallow breathing;
  • depressed mood, thoughts of suicide or hurting yourself;
  • chest tightness, fast or pounding heartbeats;
  • painful or difficult urination, urinating more or less than usual;
  • pale skin, easy bruising or bleeding; or
  • new or worsening seizures.

Less serious side effects may include:

  • drowsiness, dizziness, spinning sensation;
  • memory problems;
  • tired feeling, muscle weakness, lack of balance or coordination;
  • slurred speech;
  • drooling or dry mouth, sore gums;
  • runny or stuffy nose;
  • loss of appetite, nausea, diarrhea, constipation;
  • blurred vision;
  • headache;
  • nervousness, sleep problems (insomnia);
  • skin rash; or
  • weight changes.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

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Interactions

Cold or allergy medicine, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for depression or anxiety can add to sleepiness caused by clonazepam. Tell your doctor if you regularly use any of these medicines, or any other seizure medications.

Also tell your doctor if you are using any of the following drugs:

  • propantheline (Pro-Banthine);
  • an antifungal medication such as fluconazole (Diflucan), itraconazole (Sporanox), ketoconazole (Nizoral), or voriconazole (Vfend);
  • an antidepressant such as amitriptyline (Elavil, Etrafon), doxepin (Sinequan), imipramine (Janimine, Tofranil), nortriptyline (Pamelor), and others;
  • a barbiturate such as amobarbital (Amytal), butabarbital (Butisol), mephobarbital (Mebaral), secobarbital (Seconal), or phenobarbital (Luminal, Solfoton);
  • an MAO inhibitor such as isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate); or
  • medicines to treat psychiatric disorders, such as chlorpromazine (Thorazine), haloperidol (Haldol), mesoridazine (Serentil), pimozide (Orap), or thioridazine (Mellaril).

This list is not complete and there may be other drugs that can interact with clonazepam. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

Other Names

Klonopin, Klonopin Wafer, and clonazepam

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Disclaimer

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2004 Cerner Multum, Inc. Version 2.05. Revision date 8/23/04

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