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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Generic drug name: clonazepam (clawn AZ ah pam)
Brand name(s): KLONOPIN
GENERIC: available FAMILIES: Benzodiazepines, Drugs for Epilepsy
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

Clonazepam caused fetal malformations in animal studies, including cleft palate, open eyelid, fused backbone, and limb defects. Taking more than one drug for epilepsy increases the risk. Tell your doctor if you are pregnant or thinking of becoming pregnant before you take this drug.

Breast-feeding Warning

Clonazepam is excreted in human milk. Because of the potential for adverse effects in nursing infants, you should not take this drug while nursing.

Safety Warnings For This Drug [top]

FDA BLACK-BOX WARNING


Concomitant use (use at the same time) of benzodiazepines, including clonazepam, and opioids may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of these drugs for patients for whom alternative treatment options are inadequate. Limit dosages and durations to the minimum required. Patients must be followed for signs and symptoms of respiratory depression and sedation.

The use of benzodiazepines, including clonazepam, exposes users to risks of abuse, misuse, and addiction, which can lead to overdose or death. Abuse and misuse of benzodiazepines commonly involve concomitant use of other medications, alcohol, and/or illicit substances, which is associated with an increased frequency of serious adverse outcomes. Before prescribing clonazepam and throughout treatment, each patient’s risk for abuse, misuse, and addiction must be assessed.

The continued use of benzodiazepines, incluiding clonazepam, may lead to clinically significant physical dependence. The risks of dependence and withdrawal increase with longer treatment duration and higher daily dose. Abrupt discontinuation or rapid dosage reduction of clonazepam after continued use may precipitate acute withdrawal reactions, which can be life-threatening. To reduce the risk of withdrawal reactions, use a gradual taper to discontinue clonazepam or reduce the dosage.


Facts About This Drug [top]

Clonazepam (KLONOPIN) is approved by the Food and Drug Administration (FDA) for the control of several types of seizures in which myoclonus is a major element. Myoclonus refers to brusque, lightning-like movements of a muscle or part of a muscle, sometimes sufficiently strong enough to move an entire limb. Usually, other anticonvulsants are needed as well to control the nonmyoclonic elements of the seizure. Clonazepam is also approved for treating panic disorder.[1]

Clonazepam is a...

Clonazepam (KLONOPIN) is approved by the Food and Drug Administration (FDA) for the control of several types of seizures in which myoclonus is a major element. Myoclonus refers to brusque, lightning-like movements of a muscle or part of a muscle, sometimes sufficiently strong enough to move an entire limb. Usually, other anticonvulsants are needed as well to control the nonmyoclonic elements of the seizure. Clonazepam is also approved for treating panic disorder.[1]

Clonazepam is a benzodiazepine, a class of drugs that also includes diazepam (VALIUM), alprazolam (XANAX), chlordiazepoxide (LIBRIUM) and triazolam (HALCION). These drugs are overprescribed in the U.S. Elderly people are usually more sensitive to the central nervous system effects of these drugs. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, due to the greater frequency in this group of decreased liver, kidney or heart function and of concomitant disease or other drug therapy.

Link to Alzheimer's disease

A 2014 study published in the BMJ found a link between benzodiazepine use and Alzheimer’s disease in elderly patients.[2]

Regulatory actions surrounding clonazepam

2008: The FDA issued a warning that there have been reports of suicidal behavior or ideation associated with the use of antiepileptic drugs, including clonazepam. According to the study, patients receiving these drugs had twice the risk of suicidal behavior or ideation as patients receiving placebo (a drug with no medicinal value) and this increased risk was observed as early as one week after starting the drug.[3]

In December, another advisory was issued by the FDA in which the agency stated that it had completed its analysis of reports of suicidality (suicidal behavior or thoughts) from placebo-controlled clinical trials of drugs used to treat epilepsy, psychiatric disorders and other conditions. Based on the outcome of this review, the FDA is requiring that all manufacturers of drugs in this class include a warning on their labeling and develop a Medication Guide to be provided to patients who are prescribed these drugs to inform them of the risks of suicidal thoughts or actions.[4]

2016: The FDA added a black-box warning, the strongest warning used by the FDA, to all opioid and benzodiazepine drugs stating that serious adverse effects — including respiratory depression, coma and death — have occurred when these medications are used together.[5]

2020: The FDA announced that it is requiring the Boxed Warning for all benzodiazepine drugs to describe the serious risks of abuse, misuse, addiction, physical dependence and withdrawal reactions associated with the use of all benzodiazepines. The FDA announcement emphasized that abuse and misuse can result in overdose or death, especially when benzodiazepines are combined with other medicines, such as opioid pain relievers, alcohol or illicit drugs.[6]

Before You Use This Drug [top]

Tell your doctor if you have or have had:

  • allergies to drugs
  • pregnancy or are breast-feeding
  • alcoholism
  • coma
  • shock
  • a history of drug abuse or dependence
  • epilepsy or seizures
  • glaucoma
  • liver problems
  • severe mental depression
  • myasthenia gravis
  • brain disorder
  • severe lung disease
  • mental disorder
  • kidney problem
  • sleep disorder
  • hyperactivity
  • low albumin level
  • porphyria

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • Do not drink alcohol or use other drugs that can cause drowsiness.
  • Do not increase the dose of this drug if it seems less effective after a few weeks; check with your doctor.
  • Check with your doctor before discontinuing this drug, as gradual dosage reduction may be necessary.
  • Have regular visits to your doctor during both initial and prolonged therapy.
  • Check with your doctor if physical or psychological dependence is suspected.
  • Get medical help at once if you suspect an overdose.
  • Until you know how you react to this drug, do not drive or perform other activities requiring alertness.
  • You may feel dizzy when rising from a lying or sitting position. If you are lying down, hang your legs over the side of the bed for a few minutes, then get up slowly. When getting up from a chair, stay by the chair until you are sure that you are not dizzy.
  • Carry medical identification stating your condition and that you are taking clonazepam.
  • If you plan to have any surgery, including dental, tell your doctor that you take this drug.

How to Use This Drug [top]

  • If you miss a dose, take it as soon as you remember, but skip it if it is almost time for the next dose. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Store at room temperature with lid on tightly. Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Keep out of reach of children.

Interactions with Other Drugs [top]

The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:

BENADRYL, carbamazepine, cimetidine, digoxin, DILANTIN, diphenhydramine, itraconazole, KETALAR, ketamine, ketoconazole, LANOXICAPS, LANOXIN, LUMINAL, NIZORAL, NORVIR, phenobarbital, phenytoin, ritonavir, SOLFOTON, SOMINEX FORMULA, SPORANOX, TAGAMET, TEGRETOL.

Additionally, the United States Pharmacopeia Drug Information 2003 lists central nervous system depressant (CNS) drugs including alcohol, antidepressants, antihistamines, antipsychotics, some blood pressure medications (reserpine, methyldopa, beta-blockers), motion sickness medications, muscle relaxants, narcotics, sedatives, sleeping pills and tranquilizers, as well as MS CONTIN, morphine, and ROXANOL as having interactions of major significance.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • lack of memory of events taking place after taking drug
  • anxiety
  • confusion
  • mental depression
  • fast, pounding, or irregular heartbeat
  • abnormal thinking
  • false beliefs
  • loss of sense of reality
  • disorientation
  • skin rash or itching
  • behavior changes
  • chills, fever, and sore throat
  • unusual tiredness or weakness
  • ulcers or sores in mouth or throat
  • unusual bleeding or bruising
  • uncontrolled body movements, including of the eyes
  • yellow eyes or skin
  • low blood pressure
  • muscle weakness
  • agitation, unusual excitement, irritability, or nervousness
  • aggressive behavior, hostility, or rage
  • hallucinations
  • trouble sleeping
  • seizures

Call your doctor if these symptoms continue:

  • clumsiness or unsteadiness
  • dizziness or lightheadedness
  • drowsiness
  • slurred speech
  • abdominal or stomach cramps or pain
  • blurred vision or other vision problems
  • changes in sexual desire or ability
  • constipation
  • diarrhea
  • dry mouth or increased thirst
  • false sense of well-being
  • headache
  • increased bronchial secretions or mouth watering
  • muscle spasm
  • nausea or vomiting
  • urination problems
  • trembling or shaking
  • unusual tiredness or weakness

Call your doctor if these symptoms continue after you stop taking this drug:

  • trouble sleeping
  • irritability
  • nervousness
  • abdominal or stomach cramps
  • muscle cramps
  • confusion
  • loss of sense of reality
  • increased sweating
  • mental depression
  • nausea or vomiting
  • increased sense of hearing
  • increased sensitivity to touch and pain
  • tingling, burning, or prickly sensations
  • sensitivity of eyes to light
  • fast or pounding heartbeat
  • trembling or shaking
  • hallucinations
  • paranoia
  • convulsions

Signs of overdose:

  • continuing confusion
  • decreased reflexes
  • severe drowsiness or coma
  • seizures
  • shakiness
  • slow heartbeat
  • continuing slurred speech
  • staggering
  • difficulty breathing
  • severe weakness

If you suspect an overdose, call this number to contact your poison control center: (800) 222-1222.

Periodic Tests[top]

Ask your doctor which of these tests should be done periodically while you are taking this drug:

  • reassessment of the need for clonazepam

last reviewed June 30, 2021