Clonazepam (Klonopin)

Also known as: Clonex; Iktorivil; Landsen; Lonazep; Paxam; Rivotril


Clonazepam is used to control seizures. It also is used to relieve anxiety. This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Clonazepam also is used to treat symptoms of Parkinson's disease, twitching, schizophrenia, and pain management. Talk to your doctor about the possible risks of using this drug for your condition.

Clonazepam is drug known as a benzodiazepine. It works on the nerve cells in the brain to enhance the effects of a chemical called gamma aminobutyric acid (GABA). GABA slows down nerve cell activity to cause relaxation and decrease nerve excitement.

Before Taking this Medication

Before taking clonazepam,

  • tell your doctor and pharmacist if you are allergic to clonazepam, alprazolam (Xanax), chlordiazepoxide (Librium, Librax), clorazepate (Tranxene), diazepam (Valium), estazolam (ProSom), flurazepam (Dalmane), lorazepam (Ativan), oxazepam (Serax), prazepam (Centrax), temazepam (Restoril), triazolam (Halcion), or any other drugs.
  • tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially antihistamines; cimetadine (Tagamet); digoxin (Lanoxin); disulfiram (Antabuse); fluoxetine (Prozac); isoniazide (INH, Laniazid, Nydrazid); ketoconazole (Nizoral); levodopa (Larodopa, Sinemet); medications for depression, seizures, pain, Parkinson's disease, asthma, colds, or allergies; metoprolol (Lopressor, Toprol XL), muscle relaxants; oral contraceptives; phenytoin (Dilantin); probenecid (Benemid); propoxyphene (Darvon); propranolol (Inderal); rifampin (Rifadin); sedatives; sleeping pills; theophylline (Theo-Dur); tranquilizers; valproic acid (Depakene); and vitamins. These medications may add to the drowsiness caused by clonazepam.
  • tell your doctor if you have or have ever had glaucoma; seizures; or lung, heart, or liver disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking clonazepam, call your doctor immediately.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking clonazepam.
  • you should know that this drug may make you drowsy. Do not drive a car or operate machinery until you know how this drug affects you.
  • remember that alcohol can add to the drowsiness caused by this drug.
  • tell your doctor if you use tobacco products. Cigarette smoking may decrease the effectiveness of this drug.

Side Effects

Side effects from clonazepam are common and include:

  • drowsiness
  • dizziness
  • tiredness
  • weakness
  • dry mouth
  • diarrhea
  • upset stomach
  • changes in appetite
Tell your doctor if any of these symptoms are severe or do not go away:
  • restlessness or excitement
  • constipation
  • difficulty urinating
  • frequent urination
  • blurred vision
  • changes in sex drive or ability
If you experience any of the following symptoms, call your doctor immediately:
  • seizures
  • shuffling walk
  • persistent, fine tremor or inability to sit still
  • fever
  • difficulty breathing or swallowing
  • severe skin rash
  • yellowing of the skin or eyes
  • irregular heartbeat

Interactions with Other Drugs

Some interactions between medications can be more severe than others. The best way for you to avoid harmful interactions is to tell your doctor and/or pharmacist what medications you are currently taking, including any over-the-counter products, vitamins, and herbals. For specific information on how Clonazepam interacts with other drugs and the severity of those interactions, please use our Drug Interactions databaser to check for possible drug interactions.

Taking this Medication

Clonazepam comes as a tablet to take by mouth. It usually is taken three times a day and may be taken with or without food. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take clonazepam exactly as directed. Clonazepam can be habit-forming. Do not take a larger dose, take it more often, or for a longer time than your doctor tells you to. Tolerance may develop with long-term or excessive use, making the drug less effective. This medication must be taken regularly to be effective. Do not skip doses even if you feel that you do not need them. Do not take clonazepam for more than 4 months or stop taking this medication without talking to your doctor. Stopping the drug suddenly can worsen your condition and cause withdrawal symptoms (anxiousness, sleeplessness, and irritability). Your doctor probably will decrease your dose gradually.

Missing a Dose

If you take several doses per day and miss a dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Storing this Medication

Keep this medication in the container it came in, tightly closed and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

Last reviewed: By John M. Grohol, Psy.D. on 19 May 2015
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