Carbamazepine (Tegretol®, Tegretol CR® and generic forms) belongs to a group of medications called “mood stabilizers” or “anticonvulsants.”
What is this medication used for?
Carbamazepine is approved by Health Canada for the treatment of seizure disorders (epilepsy) in children 6 years of age and older. It is also approved for treatment of bipolar disorder and severe facial nerve pain in adults.
When potential benefits outweigh risks, carbamazepine may be used “off-label” for treatment of manic episodes associated with bipolar disorder, prevention of future manic episodes associated with bipolar disorder, and management of alcohol withdrawal syndrome. Learn more about off-label medication use: http://bit.ly/KMH-off-label-use
Tell your doctor or pharmacist if you:
- Have allergies or bad reactions to a medication
- Take (or plan to take) other prescription or non- prescription medications, including natural medicines. Some medications interact with carbamazepine. Your doctor may adjust medication doses or monitor for side effects
- Have a history of heart, kidney or liver disease, diabetes, seizures, blood disorders, glaucoma or skin reactions to medications
- Miss a menstrual period, are pregnant, breast-feeding or planning a pregnancy
- Use alcohol or drugs. Taking carbamazepine together with certain substances may cause a bad reaction. Learn more at www.DrugCocktails.ca
When will the medication start to work?
When used to control a manic episode, carbamazepine needs to be taken for 1 to 2 weeks before you notice an improvement in your symptoms. You may notice an improvement earlier if carbamazepine is combined with other medications. A delay in response is normal.
It is important that you continue taking carbamazepine regularly, even if you are feeling well or there are no improvements in the first few weeks. Talk with your doctor if you feel that carbamazepine has not been helpful or if side effects are too bothersome. Your doctor may recommend switching you to a different medication.
This medication is not addictive. Do not stop taking it before talking to your doctor.
How do I take this medication?
Carbamazepine is usually taken two to four times a day, at the same time(s) each day with food. Usually, you will start with a low dose and slowly increase this dose over several days or weeks, based on how you tolerate it.
Your doctor may ask you to have blood tests to measure the amount of carbamazepine in your blood. Do not take your carbamazepine dose just before a blood test as this can affect your results. Instead, take your dose right after the blood test is completed.
There are several forms of carbamazepine: tablets, controlled-release (CR) tablets, chewable tablets and a liquid. If necessary, carbamazepine CR tablets may be broken in half, but they should not be crushed or chewed. If you take the liquid form, shake the bottle well before each use.
Possible common or serious side effects:
Side effects may be more common when starting a medication or after a dose increase. Talk to your doctor, nurse or pharmacist if any side effect concerns you.
- Dizziness, clouded thinking, headache, or confusion
- Drowsiness, clumsiness or unsteadiness
- Blurred or double vision
- Stomach ache, nausea or vomiting
- Increased sensitivity to the sun
- Minor itching
Contact your doctor immediately if you experience:
- Seizure, agitation, unusual confusion, chills or muscle twitching
- Fever, sore throat, infection, mouth ulcers or unusual bruising or bleeding
- Unusual nausea
- Irregular heartbeat or chest pain
- Swelling in the face, ankles, feet or lower legs
- Yellowish skin/eyes, itchiness or dark colored urine
- Thoughts of hurting yourself, suicide, increased hostility or worsening symptoms
What precautions should my doctor and I be aware of when taking this medication?
- Many medications may interact with carbamazepine, including birth control pills, antihistamines, anti-anxiety medications, some antidepressants, some anticonvulsants and several other medications. If you are (or begin) taking any other prescription, over-the counter medication, natural health product or supplement, check with your doctor or pharmacist to see if they are safe to use.
- Carbamazepine may interact with grapefruit. While taking this medication, avoid eating grapefruit or drinking grapefruit juice as this may lead to increased side effects.
- While taking this medication, if you feel dizzy, drowsy or slowed down, do not drive a car or operate heavy machinery. Alcohol could make this worse. Try to avoid alcohol while taking carbamazepine.
How do I store this medication?
Keep this medication in the original container, stored at room temperature away from moisture and heat and protected from light. Keep this medication out of reach and sight of children.
How does this medication work?
Carbamazepine affects actions of the brain chemicals GABA and glutamate. This has a “stabilizing” effect on nerves, which helps reduce the spread of seizure activity in the brain and severe mood fluctuations (such as mania) associated with bipolar disorder. The exact way carbamazepine treats bipolar disorder is not fully known.
What special instructions should I follow while using this medication?
- Keep all appointments with your doctor and the lab. Your doctor may order lab tests to check how you are responding and monitor for side effects.
- Try to keep a healthy, well-balanced diet and exercise regularly. Some people may gain weight as a result of increased appetite.
- Wear sunscreen and sunglasses as carbamazepine increases sensitivity to the sun.
- Do not allow anyone else to use your medication.
What should I do if I forget to take a dose of this medication?
If you forget to take a dose, take the missed dose as soon as you remember. However, if it is within 4 hours of your next scheduled dose, skip the missed dose and continue with your regular schedule. DO NOT double your next dose to try to ‘catch up’.
How well does the medication work in children and adolescents?
Evidence from adults shows that carbamazepine helps reduce symptoms of a manic episode associated with bipolar disorder, as well as prevents future manic episodes from occurring. Carbamazepine may be used alone or in combination with other mood stabilizers to manage bipolar disorder. When effective, carbamazepine helps to stabilize mood, control emotions and improve overall functioning.
Carbamazepine may be helpful for people who have symptoms of mania and depression occurring at the same time, or those who have more than four mood episodes per year. This medication may also help manage aggressive or impulsive behavioural problems, alcohol withdrawal symptoms, or mania associated with neurological disorders.
How long should I take the medication for?
This depends on the symptoms you have, how frequently they occur, and how long you have had them. Most people with bipolar disorder need to take carbamazepine for at least 6 months. This allows time for symptoms to stabilize and for function to improve.
Your doctor will discuss the benefits and risks of taking carbamazepine with you. At this time, you can also discuss how long you might need to take this medication. If you have epilepsy or bipolar disorder and you tolerate this medication well, you may be asked to take this medication on an ongoing basis.
Do not increase, decrease, or stop taking this medication without discussing it with your doctor. If you stop taking carbamazepine suddenly, it is possible that your symptoms may return or you may experience a seizure.
