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Klonopin: 7 things you should know

Medically reviewed by Carmen Fookes, BPharm. Last updated on Feb 28, 2023.

1. How it works

  • Klonopin is a brand (trade) name for clonazepam which may be used to treat certain mood disorders or seizures.
  • Experts aren't sure exactly how Klonopin works to stabilize mood or reduce seizures but experts believe it involves enhancing the activity of GABA (gamma-aminobutyric acid) in the brain. This produces a hypnosis (a trancelike state) and decreases abnormal electrical activity.
  • Clonazepam belongs to the class of medicines called benzodiazepines.

2. Upsides

  • May be used in the treatment of panic disorder, with or without agoraphobia (fear of places or situations that make you panic).
  • May be used as the sole treatment or in addition to other medications in people with Lennox Gastaut syndrome, myoclonic seizures, or other seizure disorders.
  • May be used to treat absence seizures (petit mal seizures) that have not responded to succinimides (such as ethosuximide).
  • May also be used off-label for some other conditions.
  • Calms and sedates.
  • Klonopin is available as a generic under the name of clonazepam.

3. Downsides

If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:

  • Drowsiness, depression, dizziness, ataxia (the loss of full control of body movements), body aches and pains, palpitations, memory disturbance, increased salivation, headache, sinusitis, and tiredness have all been reported.
  • Clonazepam is potentially addictive and may cause emotional or physical dependence.
  • Withdrawal symptoms (including convulsions, tremors, cramps, vomiting, sweating, or insomnia) may occur with abrupt discontinuation; taper off slowly under a doctor's supervision. Abrupt discontinuation may also precipitate prolonged seizures when used in people with seizure disorders.
  • Drowsiness caused by Klonopin may impair judgment and affect your ability to drive or operate machinery. May also increase the risk of falls. Avoid alcohol.
  • Klonopin, as with similar drugs used in the treatment of epilepsy or depression, can increase the risk of suicidal thoughts or behavior. Monitor mood.
  • Avoid combining Klonopin with opioids such as oxycodone or hydrocodone. Profound sedation, respiratory depression (abnormally slow and shallow breathing), coma, and death may result. May also interact with several other drugs including those that induce or inhibit cytochrome 4503A hepatic enzymes.
  • The effectiveness of Klonopin long-term has not been established. Long-term use is also associated with dependence.
  • Some studies have shown that up to 30% of people taking Klonopin have shown a loss of anticonvulsant activity within three months of starting Klonopin. An increase in dosage may restore effectiveness.
  • Not suitable for people with significant liver disease or acute narrow-angle glaucoma. Dosage may need to be reduced in people with kidney disease. May not be suitable for those people whose breathing is already compromised, with a history of seizures, or who have porphyria.

Note: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. View complete list of side effects

4. Bottom Line

  • Klonopin may be used in the treatment of panic disorder and certain types of seizure disorder. Sedation is the most common side effect and it can cause both physical and psychological dependence.

5. Tips

  • Swallow tablets whole with water.
  • Klonopin is potentially addictive and can cause physical and psychological dependence. Take only as directed by your doctor. Do not increase or decrease the dosage without his or her permission. The smallest effective dose for the shortest possible time should be used. Do not discontinue suddenly without your doctor's advice. When it comes time to discontinue Klonopin, your doctor will talk to you about a tapering schedule.
  • Do not take Klonopin with opioids (be aware that some opioids are contained in over-the-counter cough or cold products). Always talk with your pharmacist or doctor before buying over-the-counter medications to check that they are compatible with Klonopin.
  • Do not drive or operate machinery if Klonopin makes you drowsy or impairs your judgment.
  • Do not drink alcohol while taking Klonopin because this may make side effects such as respiratory depression and sedation worse.
  • If your mood changes or you develop depression, a worsening of depression, or a worsening of seizures, talk with your doctor.
  • Seek immediate medical help if you have difficulty breathing while taking Klonopin.
  • Do not start or discontinue Klonopin during pregnancy without speaking to your provider first.
  • Women should not breastfeed their babies while receiving Klonopin.

6. Response and effectiveness

  • Klonopin is quickly absorbed and peak concentrations are reached within 1 to 4 hours. One dose can last up to 24 hours; however, split dosages throughout the day may be preferred.

7. Interactions

Medicines that interact with Klonopin may either decrease its effect, affect how long it works, increase side effects, or have less of an effect when taken with Klonopin. An interaction between two medications does not always mean that you must stop taking one of the medications; however, sometimes it does. Speak to your doctor about how drug interactions should be managed.

Common medications that may interact with Klonopin include:

  • anti-anxiety medications, including other benzodiazepines, such as diazepam and oxazepam
  • anticonvulsants such as phenytoin
  • antidepressants, such as amitriptyline, imipramine, nortriptyline
  • antihistamines that cause sedation, such as diphenhydramine
  • duloxetine
  • monoamine oxidase inhibitors, such as selegiline, isocarboxazid, or phenelzine (interaction may be life-threatening)
  • opioid analgesics such as oxycodone and morphine
  • muscle relaxants such as cyclobenzaprine
  • sleeping pills, such as zolpidem
  • some chemotherapy treatments
  • some medications used to treat mental illness, such as clozapine and thioridazine.

Alcohol may worsen the side effects of Klonopin such as drowsiness and dizziness.

Note that this list is not all-inclusive and includes only common medications that may interact with Klonopin. You should refer to the prescribing information for Klonopin for a complete list of interactions.


Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Klonopin only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Copyright 1996-2023 Revision date: February 27, 2023.