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Clonazepam - What is it for

​Clonazepam belongs to a class of medications known as benzodiazepines.

It can be used for short-term treatment of insomnia (difficulty sleeping), anxiety or panic.

It may also be used for other conditions such as epilepsy (fits). Check with your healthcare professional if you are unsure why you are given this medication.

Clonazepam - Side Effects, Precautions, and Contraindications

What side effects can Clonazepam cause?

​The mentioned side effects generally affect up to 10% of patients.

  • Nausea or stomach discomfort
    • Take this medication with or after food
    • Take simple meals and avoid rich or spicy foods
  • Constipation
    • Drink more water (if not on fluid-restricted diet), eat more high-fibre foods, and exercise regularly
    • Speak to your doctor or pharmacist if you need a medication to help with your constipation
  • Light-headedness (especially during a sudden change in posture)
    • Get up slowly from a sitting or lying down position
  • Feeling tired or drowsy
    • Discuss with your doctor if you can take this medication at a different time of the day
    • Avoid driving or engaging in activities requiring concentration
  • Feeling clumsy or unsteady
    • Speak to your doctor if it bothers you

Most of the side effects listed here will improve with time. Speak to your doctor if they continue, get worse or are affecting your daily life.

Rarely this medication may cause:

  • Memory loss (amnesia)
  • Abnormal thinking, changes in behaviour, or hearing or seeing things that do not exist (hallucinations)
  • Unusual excitement, irritability, or agitation (disinhibition)
  • Unusual sleep-related activities such as walking, eating or cooking
  • Confusion
  • Fast, slow or irregular heartbeat
  • Blurred vision
  • Severe muscle weakness
  • Dark brown urine, light coloured stools (pale grey/clay-coloured), yellowing of skin and eyes (symptoms of liver problems)

The symptoms of a drug allergy include one or more of the following:

  • Swollen face/eyes/lips/tongue
  • Difficulty in breathing
  • Itchy skin rashes over your whole body

If you experience any of these side effects, you should stop your medication and inform your healthcare professional immediately.

Please also take note that not all possible side effects are listed above. If you have any concerns about your medication, please consult your doctor or pharmacist.

Before taking Clonazepam , what precautions must I follow?

​Inform your healthcare professional if:

  • You are allergic to this medication or any of the other ingredients of this medication.
  • You are pregnant, planning to become pregnant, or breastfeeding. If you are pregnant and/or breastfeeding, your doctor would have discussed the potential benefits and side-effects with you. If you have further questions or concerns, do consult your doctor.
  • You are taking any other medications including over-the-counter medications, supplements, traditional Chinese medicine and herbal remedies. Some of them may affect how this medication works or cause serious drug interactions.
  • You have or have ever had:
    • Other drug allergies
    • Other mental health conditions such as depression
    • Medical conditions such as:
      • Lung, brain, kidney or liver disease
      • Previous drug or alcohol abuse
      • Glaucoma (high pressure in the eyes), seizures (fits), Myasthenia Gravis (an autoimmune condition that affects the nerves and muscles) or sleep apnea (temporary stopping of breathing during sleep)

This medication may be habit-forming when taken excessively or for a prolonged duration (especially at high doses). This may result in:

  • Unintentional, regular use of the medication
  • Dependence or over-reliance on the medication
  • Decreased effectiveness of the medication

This can be prevented by taking the medication:

  • On a short-term basis (2 - 4 weeks)
  • At the lowest effective dose
  • Intermittently (for example, taking it once every 2 or 3 nights for the relief of sleep difficulty)

If you have been taking the medication on a long-term basis or at high doses, do not stop taking it abruptly as it may lead to withdrawal symptoms such as increased sweating, increased heart rate, tremors, trouble sleeping, increased agitation, hallucinations, increased anxiety, nausea or vomiting, and in severe cases, medical emergencies such as fits.

If you wish to cut down, discuss with your doctor to come up with a discontinuation plan. It is often best to reduce the dose gradually over a few weeks.

If you are prescribed this medication for other conditions such as epilepsy (fits), consult your doctor or specialist for further advice about the appropriate dose and duration.

What food or medicine must I avoid when I take Clonazepam ?

​Avoid drinking alcohol while taking this medication as it can cause excessive drowsiness.

Clonazepam - Dosage and How to Use

How should Clonazepam be used?

  • Follow the instructions on your medication label and take this medication as prescribed by your doctor.
  • This medication may be taken with or without food.
  • If you feel that the medication is not working well, please consult your doctor.
  • You should obtain this medication from the same doctor or clinic whenever possible.

What should I do if I miss a dose?

​If you are directed by your doctor to take the medication regularly and forget to take a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the next dose at your usual timing. Do not take two doses to make up for the missed dose.

What should I do if I overdose?

Clonazepam - Handling

How should I handle Clonazepam safely?

Clonazepam - Storage

How should I store Clonazepam ?

;#Keep away from children;#Keep in a cool, dry place, away from direct sunlight;#

How should I dispose of Clonazepam safely?

​Pack this medication into a trash bag and seal it tightly before throwing into the rubbish chute or bin.

Clonazepam - Additional Information

  • Updated on 10/31/2021 12:00:00 AM
  • Article contributed by PSS National Medication Information Workgroup PSS National Medication Information Workgroup
The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth

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