Generic Name: clonazepam (kloe-NAZ-e-pam) (Oral route)
Concomitant use of benzodiazepines and opioids may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing for patients with inadequate alternative treatment options. Limit dosages and durations to the minimum required and follow patients for signs and symptoms of respiratory depression and sedation .
Medically reviewed by Drugs.com. Last updated on May 8, 2020.
Commonly used brand name(s)
In the U.S.
- KlonoPIN Wafers
Available Dosage Forms:
- Tablet, Disintegrating
Therapeutic Class: Antianxiety
Pharmacologic Class: Benzodiazepine, Short or Intermediate Acting
Uses for Klonopin
Clonazepam is used alone or together with other medicines to treat certain seizure disorders (eg, Lennox-Gastaut syndrome, akinetic, myoclonic, and absence seizures). It is also used to treat panic disorder. Clonazepam is a benzodiazepine that works in the brain to prevent seizures. Benzodiazepines are central nervous system (CNS) depressants, which are medicines that slow down the nervous system.
This medicine is available only with your doctor's prescription.
Before using Klonopin
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of clonazepam in children with seizure disorders. However, safety and efficacy in children with panic disorder have not been established.
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of clonazepam in the elderly. However, elderly patients are more likely to have confusion and severe drowsiness, or age-related heart, liver, or kidney problems, which may require caution and an adjustment in the dose for patients receiving clonazepam.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Calcium Oxybate
- Chloral Hydrate
- Gabapentin Enacarbil
- Magnesium Oxybate
- Morphine Sulfate Liposome
- Potassium Oxybate
- Sodium Oxybate
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- St John's Wort
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following is usually not recommended, but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco.
Other medical problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Depression, history of or
- Lung or breathing problems or
- Porphyria—Use with caution. May make these conditions worse.
- Glaucoma, narrow angle, acute or
- Liver disease—Should not be used in patients with these conditions.
- Kidney disease—Use with caution. The effects may be increased because of slower removal of the medicine from the body.
Proper use of Klonopin
This section provides information on the proper use of a number of products that contain clonazepam. It may not be specific to Klonopin. Please read with care.
Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.
This medicine should come with a Medication Guide. Read and follow these instructions carefully. Ask your doctor if you have any questions.
Swallow the tablet whole with water.
If you are using the disintegrating tablet (wafer), make sure your hands are dry before you handle the tablet. Do not open the blister pack that contains the tablet until you are ready to take it. Remove the tablet from the blister pack by peeling back the foil. Do not push the tablet through the foil. Do not break or split the tablet. Place the tablet in your mouth. It should melt quickly. After the tablet has melted, you may take a sip of water.
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage forms (tablets or disintegrating tablets):
- For seizures:
- Adults and children 10 years and older—At first, 0.5 milligram (mg) 3 times per day. Your doctor may adjust your dose as needed. However, the dose is usually not more than 20 mg per day.
- Children up to 10 years or 30 kilograms (kg) of body weight—Dose is based on body weight and must be determined by your doctor. The dose is usually 0.01 to 0.03 mg per kg of body weight per day, given in 2 or 3 divided doses. However, the dose is usually not more than 0.05 mg per kg of body weight. Your doctor may adjust your dose as needed.
- For panic disorder:
- Adults—At first, 0.25 milligram (mg) 2 times per day. Your doctor may adjust your dose as needed. However, the dose is usually not more than 4 mg per day.
- Children—Use and dose must be determined by your doctor.
- For seizures:
If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Precautions while using Klonopin
It is very important that your doctor check your progress at regular visits to see if the medicine is working properly and to allow for changes in the dose. Blood tests may be needed to check for unwanted effects.
Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using the medicine, tell your doctor right away.
This medicine may be habit-forming. If you feel that the medicine is not working as well, do not use more than your prescribed dose. Call your doctor for instructions.
This medicine may cause drowsiness, trouble with thinking, trouble with controlling movements, or trouble with seeing clearly. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are not alert or able to think or see well.
If you develop any unusual and strange thoughts or behavior while you are taking clonazepam, be sure to discuss it with your doctor. Some changes that have occurred in people taking this medicine are like those seen in people who drink alcohol and then act in a manner that is not normal. Other changes may be more unusual and extreme, such as confusion, worsening of depression, hallucinations (seeing, hearing, or feeling things that are not there), suicidal thoughts, and unusual excitement, nervousness, or irritability.
If you have been taking this medicine for a long time, do not stop taking it without checking first with your doctor. Your doctor may want you to gradually reduce the amount you are using before stopping it completely. This may help prevent worsening of your condition and reduce the possibility of withdrawal symptoms, such as seizures, hallucinations, stomach or muscle cramps, tremors, or unusual behavior.
This medicine will add to the effects of alcohol and other central nervous system (CNS) depressants. CNS depressants are medicines that slow down the nervous system, which may cause drowsiness or make you less alert. Some examples of CNS depressants are antihistamines or medicine for hay fever, allergies or colds, sedatives, tranquilizers, or sleeping medicine, prescription pain medicine or narcotics, barbiturates or seizure medicines, muscle relaxants, or anesthetics (numbing medicines), including some dental anesthetics. Check with your doctor before taking any of these products while you are using this medicine.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
Klonopin side effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
- Body aches or pain
- difficulty breathing
- ear congestion
- feeling sad or empty
- lack of appetite
- loss of interest or pleasure
- loss of voice
- nasal congestion
- poor coordination
- runny nose
- shakiness and unsteady walk
- sleepiness or unusual drowsiness
- sore throat
- trouble concentrating
- trouble sleeping
- unsteadiness, trembling, or other problems with muscle control or coordination
- unusual tiredness or weakness
- Being forgetful
- bladder pain
- bloody or cloudy urine
- change in speech
- difficult, burning, or painful urination
- frequent urge to urinate
- general feeling of discomfort or illness
- joint pain
- loss of appetite
- lower back or side pain
- mood or mental changes
- muscle aches and pains
- problems in urination or increase in the amount of urine
- slurred speech
- sore throat
- trouble speaking
- Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
- changes in skin color
- chest pain or discomfort
- cold sweats
- cough or hoarseness
- difficulty with sleeping
- dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
- excessive dreaming
- excessive muscle tone
- fast, irregular, pounding, or racing heartbeat or pulse
- feeling mad
- feeling of unreality
- flu-like symptoms
- headache, severe and throbbing
- lack of feeling or emotion
- lack or loss of self-control
- muscle stiffness
- muscle tension or tightness
- pain, inflammation, or swelling in the calves, shoulders, or hands
- pain or swelling in the arms or legs without any injury
- pain, tenderness, or swelling of the foot or leg
- partial or slight paralysis
- sense of detachment from self or body
- shakiness in the legs, arms, hands, or feet
- skin rash
- swelling around the eyes
- swelling of the face, ankle, foot, or knees
- thoughts of killing oneself changes in behavior
- tightness in the chest
- trembling or shaking of the hands or feet
- vision changes
Incidence not known
- Abdominal pain or fullness
- black, tarry stools
- bleeding gums
- blood in the urine or stools
- change in consciousness
- chest congestion
- difficulty with coordination
- double vision
- dry mouth
- feeling that others are watching you or controlling your behavior
- feeling that others can hear your thoughts
- feeling, seeing, or hearing things that are not there
- irregular, fast, slow, or shallow breathing
- irregular, twisting uncontrolled movement of the face, hands, arms, or legs
- loss of interest or pleasure
- loss of memory
- loss of strength or energy
- loss of voice
- muscle weakness
- pale or blue lips, fingernails, or skin
- pinpoint red spots on the skin
- problems with memory
- severe mood or mental changes
- sores, ulcers, or white spots on the lips or in the mouth
- swollen glands
- troubled breathing with exertion
- uncontrolled eye movements
- unusual behavior
- unusual bleeding or bruising
- unusual weakness
- vivid dreams
- weight loss or gain
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
- Decreased interest in sexual intercourse
- difficulty with swallowing
- dryness or soreness of the throat
- heavy bleeding
- inability to have or keep an erection
- longer than usual time to ejaculation of semen
- loss in sexual ability, desire, drive, or performance
- pain or tenderness around the eyes and cheekbones
- puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
- voice changes
- Acid or sour stomach
- ankle, knee, or great toe joint pain
- bleeding after defecation
- blistering, burning, crusting, dryness, or flaking of the skin
- blurred or loss of vision
- change in color perception
- cracks in the skin at the corners of the mouth
- decrease or change in vision
- difficulty moving
- double vision
- dryness of the eyes
- excess air or gas in stomach or intestines
- feeling of constant movement of self or surroundings
- feeling of warmth
- frequent bowel movements
- full feeling
- hair loss or thinning of the hair
- halos around lights
- increased watering of the mouth
- irregularities in menstruation
- itching in the genital or other skin areas
- itching, scaling, severe redness, soreness, or swelling of the skin
- joint stiffness or swelling
- leg or muscle cramps
- loss of taste
- night blindness
- overbright appearance of lights
- pain in the breasts or pelvic area
- pain in the leg, nape, or back
- passing gas
- red, sore eyes
- redness of the face, neck, arms, and occasionally, upper chest
- redness or swelling in the ear
- sensation of spinning
- smaller amount of semen ejaculated than usual
- sore on the edge of the eyelid
- soreness or redness around the fingernails and toenails
- stomach discomfort, upset, or pain
- thickening of the tongue
- tooth disorder
- tunnel vision
- twitching of the eyes
- uncomfortable swelling around the anus
- worsening of acne
Incidence not known
- Burning feeling in the chest or stomach
- difficulty having a bowel movement (stool)
- increased appetite
- increased hair growth, especially on the face
- increased in sexual ability, desire, drive, or performance
- increased interest in sexual intercourse
- sore gums
- tenderness in the stomach area
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Frequently asked questions
More about Klonopin (clonazepam)
- Side Effects
- During Pregnancy or Breastfeeding
- Dosage Information
- Patient Tips
- Drug Images
- Drug Interactions
- Compare Alternatives
- Support Group
- Pricing & Coupons
- En Español
- 264 Reviews
- Generic Availability
- Drug class: benzodiazepine anticonvulsants
- FDA Alerts (1)
- Other brands
- Klonopin Wafer
Related treatment guides
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.