The carbamazepine (CBZ) , sold under the trade name Tegretol , among others, is a drug used primarily in the treatment of epilepsy and neuropathic pain. It is not effective for absence seizures or myoclonic seizures. It is used in schizophrenia along with other medications and as a second-line agent in bipolar disorder. Carbamazepine appears to work as well as phenytoin and valproate.
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Carbamazepine – Uses
Medical uses
Carbamazepine was discovered in 1953 by Swiss chemist Walter Schindler. It was first marketed in 1962. It is available as a generic drug.
Carbamazepine is generally used to treat seizure disorders and neuropathic pain. It is not effective for absence seizures or myoclonic seizures.
In the United States, FDA-approved medical uses are epilepsy (including partial seizures, generalized tonic-clonic seizures, and mixed seizures), trigeminal neuralgia, and manic and mixed episodes of bipolar I disorder. The drug is also claimed to be effective. for ADHD.
Carbamazepine – Dosage and Administration
Usual adult dose of carbamazepine for epilepsy:
Starting dose: 200 mg orally 2 times a day (immediate and prolonged release) or 100 mg orally 4 times a day (suspension)
Increase the dose at weekly intervals by adding up to 200 mg / day using an extended-release regimen of 2 times a day or a regimen of 3 times a day or 4 times a day of the other formulations.
Maintenance dose: 800 to 1200 mg / day.
The dose should generally not exceed 1200 mg / day.
However, on rare occasions doses of up to 1600 mg / day have been used.
Usual adult dose for trigeminal neuralgia:
– Initial dose: 100 mg orally 2 times a day (immediate or prolonged release) or 50 mg orally 4 times a day (suspension)
-Can increase up to 200 mg per day in increments of 100 mg every 12 hours (release immediate or prolonged), or 50 mg 4 times a day (suspension), only when necessary to relieve pain. Do not exceed 1200 mg per day.
– Maintenance dose: 400 to 800 mg per day
Dosage for epilepsy:
Less than 6 years of age:
– Initial dose: 10 to 20 mg / kg / day orally in 2 to 3 divided doses (tablets) or 4 divided doses (suspension)
-Increase the dose at weekly intervals to achieve a clinical response optimal administered 3 or 4 times a day.
– Maximum dose: 35 mg / kg / day
-If a satisfactory response is not achieved, measure plasma levels to determine if it is within the therapeutic range.
-Comments: The manufacturer does not make any recommendation regarding the safety of doses above 35 mg / kg / 24 hours.
6 to 12 years of age:
– Starting dose: 100 mg orally 2 times a day (immediate-release or extended-release tablets) or 50 mg orally 4 times a day (suspension)
-Increase the dose at weekly intervals in increments of 100 mg per day using an extended release regimen of 2 times a day or a regimen of 3 times a day or 4 times a day of the other formulations.
Maintenance dose: 400 to 800 mg per day
Maximum dose: 1000 mg per day
Over 12 years of age:
– Initial dose: 200 mg orally 2 times a day (immediate and prolonged release) or 100 mg orally 4 times a day (suspension)
-Increase the dose at weekly intervals in increments of 200 mg per day using a 2 times a day extended release regimen or a 3 times a day to 4 times a day regimen of the other formulations.
– Maintenance dose: 800 to 1200 mg per day
Carbamazepine – Side Effects
Common side effects include nausea and drowsiness. Serious side effects can include skin rash, decreased bone marrow function, suicidal thoughts, or confusion. It should not be used in people with a history of bone marrow problems. Use during pregnancy may harm the baby; however, it is not recommended to stop it in pregnant women with seizures.
Carbamazepine – Warnings
In the US, the carbamazepine label contains warnings about:
Effects on the production of red blood cells, white blood cells and platelets in the body: The main effects of aplastic anemia and agranulocytosis are rarely reported and more often there are minor changes such as decreased white blood cell counts or platelets, but these do not progress to more serious problems.
- increased suicide risks
- increased risks of hyponatraemia and SIADH
- risk of seizures, if the person stops taking the medicine abruptly
- risks to the fetus in pregnant women, specifically congenital malformations such as spina bifida and developmental disorders.
Common adverse effects can include drowsiness, dizziness, headaches and migraines, impaired motor coordination, nausea, vomiting, and / or constipation. Drinking alcohol while taking carbamazepine can lead to increased central nervous system depression. Less common side effects may include an increased risk of seizures in people with mixed seizure disorders, abnormal heart rhythms, blurred or double vision.
Carbamazepine – Interactions
Carbamazepine has the potential for drug interactions; Caution should be exercised when combining other medications with it, including other antiepileptics and mood stabilizers. Lower levels of carbamazepine are seen when phenobarbital, phenytoin, or primidone are administered, which can lead to disruptive seizure activity.
Carbamazepine also increases the metabolism of hormones in birth control pills and can reduce their effectiveness, which can lead to unexpected pregnancies. As a drug that induces cytochrome P450 enzymes, it accelerates the elimination of many benzodiazepines and decreases their action.
Dr. Samantha Robson ( CRN: 0510146-5) is a nutritionist and website content reviewer related to her area of expertise. With a postgraduate degree in Nutrition from The University of Arizona, she is a specialist in Sports Nutrition from Oxford University and is also a member of the International Society of Sports Nutrition.
