Clonazepam is a benzodiazepine. It affects chemicals in the brain that may be unbalanced to treat seizures and certain types of anxiety disorders.
Clonazepam, a type of anti-epileptic drug, is used to treat certain seizure disorders (including absence seizures or Lennox-Gastaut syndrome) in adults and children. It is also used to treat panic disorder (including agoraphobia) in adults.
Before taking this medicine
You should not take clonazepam if you have:
- narrow-angle glaucoma;
- severe liver disease; or
- a history of allergic reaction to any benzodiazepine, such as diazepam (Valium), alprazolam (Xanax), lorazepam (Ativan), chlordiazepoxide, flurazepam, and others.
To make sure clonazepam is safe for you, tell your doctor if you have ever had:
- kidney or liver disease;
- porphyria (a genetic enzyme disorder that causes symptoms affecting the skin or nervous system);
- asthma, emphysema, bronchitis, chronic obstructive pulmonary disorder (COPD), or other breathing problems;
- depression or suicidal thoughts or behavior;
- mental illness, psychosis, or addiction to drugs or alcohol; or
- if you use a narcotic (opioid) medication.
Some people have thoughts about suicide when taking seizure medication. Your doctor should check your progress at regular visits. Your family or other caregivers should also be alert to changes in your mood or symptoms.
Follow your doctor’s instructions about taking seizure medication if you are pregnant. Do not start or stop taking this medicine without your doctor’s advice, and tell your doctor right away if you become pregnant. Clonazepam may cause harm to an unborn baby, and may cause breathing or feeding problems in a newborn. But having seizures during pregnancy could harm both mother and baby.
If you are pregnant, your name may be listed on a pregnancy registry. This is to track the outcome of the pregnancy and to evaluate any effects of clonazepam on the baby.
Clonazepam can pass into breast milk, but effects on the nursing baby are not known. Tell your doctor if you are breast-feeding
NOTE: Do not give this medicine to a child without medical advice. Clonazepam is not approved to treat panic disorder in anyone younger than 18 years old.
How should I take clonazepam?
Take clonazepam exactly as prescribed by your doctor. Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not use this medicine in larger or smaller amounts or for longer than recommended.
Clonazepam may be habit-forming. Never share this medicine with another person, especially someone with a history of drug abuse or addiction. Keep the medication in a place where others cannot get to it.
Misuse of habit-forming medicine can cause addiction, overdose, or death. Selling or giving away this medicine is against the law.
Clonazepam should be used for only a short time. Do not take this medication for longer than 9 weeks without your doctor’s advice. If you use this medicine long-term, you may need frequent medical tests.
Swallow the tablet whole, with a full glass of water.
Do not stop using clonazepam suddenly or you could have unpleasant withdrawal symptoms, including a seizure (convulsions). Ask your doctor how to safely stop using this medicine. Call your doctor if this medicine seems to stop working as well in treating your seizures or anxiety symptoms.
Seizures are often treated with a combination of drugs. Use all medications as directed by your doctor. Read the medication guide or patient instructions provided with each medication. Do not change your doses or medication schedule without your doctor’s advice.
Store clonazepam at room temperature away from moisture, heat, and light.
Keep track of the amount of medicine used from each new bottle. Clonazepam is a drug of abuse and you should be aware if anyone is using your medicine improperly or without a prescription.
What should I avoid while taking clonazepam?
Avoid drinking alcohol. Dangerous side effects could occur. Avoid taking similar medications, such as lorazepam (Ativan) or diazepam (Valium) as well as narcotics. Clonazepam may impair your thinking or reactions. Avoid driving or operating machinery until you know how this medicine will affect you. Dizziness or severe drowsiness can cause falls or other accidents.
Clonazepam side effects
Get emergency medical help if you have signs of an allergic reaction to clonazepam: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.
Call your doctor at once if you have:
- new or worsening seizures;
- severe drowsiness;
- unusual changes in mood or behavior;
- confusion, aggression, hallucinations;
- thoughts of suicide or hurting yourself;
- weak or shallow breathing;
- pounding heartbeats or fluttering in your chest; or
- unusual or involuntary eye movements.
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.
Common clonazepam side effects may include:
- feeling tired or depressed;
- drowsiness, dizziness;
- memory problems; or
- problems with balance or coordination.
What other drugs will affect clonazepam?
Taking this medicine with other drugs that make you sleepy or slow your breathing can cause dangerous side effects or death. Ask your doctor before taking a sleeping pill, an opioid medicine, prescription cough medicine, a muscle relaxer, or medicine for anxiety, depression, or seizures.
Other drugs may interact with clonazepam, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.
Onset of Action
~20 to 40 minutes (Hanson 1972)
Time to Peak
Serum: 1 to 4 hours
Duration of Action
Infants and young children: 6 to 8 hours (Hanson 1972); Adults: ≤12 hours