Carbamazepine is an anticonvulsant medication and mood stabilizer, typically used to treat epilepsy, seizure disorders, and occasionally Bipolar Disorder. It is important to take this medication exactly as prescribed and to consult with your doctor prior to starting any other medications (prescribed or over the counter) while taking carbamazepine, as adverse effects can occur.

Carbamazepine brand names

  • Tegretol
  • Tegretol XR
  • Carbatrol
  • Equetro
  • Epitol

What is carbamazepine prescribed for?

Carbamazepine is prescribed to treat epilepsy and prevent partial seizures. It is also prescribed as a mood stabilizer in the treatment of bipolar disorder.

Carbamazepine is also prescribed off-label, which means that it has not been approved by the US Food and Drug Administration (FDA) for these uses, but it has been deemed necessary for treatment by a doctor.

Off-label uses of carbamazepine include the treatment of various symptoms of dementia, schizophrenia, and severe pain.[1]

How does carbamazepine work?

Carbamazepine works by inhibiting or reducing certain activity in the brain, which results in a reduced occurrence of epileptic seizures and a reduction in the symptoms of bipolar, particularly mania.[1][2]

How is carbamazepine usually taken?

Carbamazepine is available as a tablet (200mg and 400mg), a chewable tablet (100mg), a liquid (100mg per 5ml), an extended-release tablet (100mg, 200mg, and 400mg), and an extended-release capsule (100mg, 200mg, and 300mg).

Extended-release tablets and capsules slowly release the medication into the body throughout the day, so often require fewer doses and help reduce fluctuations in medication levels.[2] The other forms of this medication are immediate release, so may require regular doses, up to four times per day.

Tablets must be swallowed whole, without crushing.

Chewable tablets should be chewed and swallowed, or swallowed whole if preferred.

Capsules should be swallowed whole without crushing. Alternatively, they can be opened and sprinkled over soft food such as apple sauce and swallowed without chewing.

Liquid medication must be measured with an accurate measuring device, such as a marked syringe. Your doctor will advise you on how to administer this medication, so it is important to follow their instructions exactly.

Daily doses of carbamazepine can vary from 200-1600mg, depending on the severity of your condition, your age, your weight, or your response to the medication.[3][4] You will likely never be prescribed over 1600mg in one day.

Your doctor will commence your prescription with a low dose, usually, 200mg to be taken twice per day, which can then be increased gradually to find the most effective dose for you.

Your doctor will monitor any changes in your physical and mental health, particularly at the beginning of your treatment. Regular blood tests may be required until a safe and effective dosage has been reached.

Ensure you take your medication exactly as prescribed, using the correct type of carbamazepine, the correct dose, and at the correct times.

If you forget one dose, take it as soon as you remember, or if it is near to the time of your next dose, skip the missed dose and take the next. Never take double your prescribed dose, as this can cause adverse effects and increase the risk of serious side effects.

How long does carbamazepine stay in your system?

When you begin taking carbamazepine, you may notice changes in your symptoms within the first week or two, although it will likely take several weeks before the medication takes full effect, so it is important to continue taking it consistently, exactly as prescribed.[3]

If you stop taking carbamazepine, it will take several days before the medication completely leaves your system.[5]

Never stop taking carbamazepine suddenly, even if you feel better, as this can cause withdrawal symptoms and may severely worsen your mental health. If your doctor advises that it is safe to stop this medication, they will slowly reduce your dose, to prevent adverse effects from occurring.

Bipolar Disorder often requires lifelong treatment, so you may be required to take medication consistently to manage your condition.[3]

Carbamazepine side effects

When you start a new medication, you may experience some common side effects. They will likely reduce within the first few weeks or months, but if they continue or become problematic, consult with your doctor, as you may need a reduced dose or a change of medication.

Common side effects of carbamazepine include:

  • Feeling dizzy, drowsy, or unsteady
  • Stomach upset, such as constipation, diarrhea, nausea, or vomiting
  • Dry mouth
  • Blurry vision

Serious side effects of carbamazepine are less common but may still occur. If you experience any of the following, contact your doctor immediately, as it may be a sign of a serious issue, such as low sodium levels, blood problems, or an allergic reaction:

  • Seizures
  • Confusion
  • Extreme tiredness or weakness
  • Shortness of breath
  • Fever or sweating
  • Regular infections
  • Headache
  • Unexplained bruising or bleeding
  • Swelling of the face or mouth
  • Breathing difficulties
  • Ulcers
  • Rash
  • Changes in mental state, including an increase in depression or anxiety, thoughts of harming yourself or others, mania, impulsivity, insomnia, or agitation

In rare cases, Carbamazepine has been known to cause serious skin reactions including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN).

Carbamazepine precautions

Carbamazepine may cause suicidal thoughts.[4] If you or your family notice any concerning changes in your mental state, or you have thoughts of severely harming yourself, contact a medical professional immediately.

It is important that your doctor is aware of any past or present mental health conditions you have experienced, to enable safe monitoring of your condition while on this medication, or to decide if it is safe for you.

Discuss with your doctor all your past and present physical health conditions, as they may impact your ability to take this medication safely.

Because of the potential side effects, it is important that you tell your doctor if you have experienced heart, liver, kidney, blood, or bone conditions, as it may not be safe to take this medication, or you may require increased monitoring of your physical health.[4][6]

Tell your doctor about all medications you are currently taking or plan to take (including vitamins, herbal supplements, and dietary supplements), as they may cause adverse reactions.

Discuss with your doctor if you are pregnant or planning to get pregnant, as this medication can cause harm to your fetus [3][4]. These risks can be somewhat managed if it is deemed necessary for you to take carbamazepine while pregnant and the benefits of this treatment outweigh any potential risks.

Tell your doctor if you are breastfeeding, as carbamazepine can be passed to your baby through breast milk.[1][4] Your doctor will discuss these risks with you, so you can take precautions if you decide to breastfeed while taking carbamazepine, and you can safely monitor your baby for any changes in their physical or mental state.

Carbamazepine can cause a serious skin condition, called Stevens-Johnson syndrome.[4] If you notice a rash or unusual changes to your skin, consult with your doctor immediately, so it can be safely monitored and treated.

This medication can cause drowsiness, so it is important to avoid driving until you are aware of how carbamazepine affects you and that it is safe to do so.

It is advised to avoid or limit alcohol intake while on carbamazepine, as it may decrease the effectiveness of your medication, and could increase drowsiness.[4]

Carbamazepine interactions

Some medications may interact with carbamazepine, causing a decrease in the effectiveness of your medication, or an increase in the risk of side effects.

This includes some antibiotic and antifungal medications, other mood stabilizers or seizure medications, blood thinners, medications for heart conditions or cholesterol, sedatives and tranquilizers, and various mental health medications, such as antidepressants (notably MAOIs) and antipsychotics.

Always discuss your medications with your doctor before starting a new treatment.

Grapefruit juice can cause an increase in carbamazepine levels, so it is advised to avoid eating or drinking anything containing grapefruit juice or to limit to small amounts.[3][4]

Carbamazepine storage

Always keep all medications out of reach of children.

Store carbamazepine in its original packaging, in airtight containers, and at room temperature (never above 86 F).

If you need to dispose of medication that is out of date or no longer needed, contact a medical professional to ensure it is disposed of appropriately. Never flush medications down the toilet or put them in the bin, as this can create unnecessary risks.

What to do if you overdose on carbamazepine

If you overdose on carbamazepine, call a medical professional or Poison Control on 1-800-222-1222, or in case of an emergency, call 911. Symptoms of a carbamazepine overdose include breathing difficulties, irregular heartbeat, seizure, drowsiness, vomiting, or coma.

Frequently asked questions about carbamazepine

Does carbamazepine cause weight gain?

Carbamazepine can cause some increase in weight and appetite [7]. You may wish to discuss this with your doctor and ways in which to manage your weight and physical well-being while on this medication.

Are there any alternatives to carbamazepine?

There are various medications available to treat mania associated with bipolar disorder, including lithium, other anticonvulsant medications such as valproate and lamotrigine, and antipsychotic medications such as olanzapine, risperidone, and haloperidol, while antidepressant medications can help to treat depressive episodes of bipolar disorder.[8]

You may wish to discuss alternative medications with your doctor, who can advise you on the various side effects and benefits of each medication. People often respond differently to medications, so what works well for one person may not work as well for another. You may be required to try several medications before finding one that works for you.

You may also wish to engage in talking therapies alongside your medication, as this can help you to manage your condition.[8]

Resources:

  1. Maan, J.S., Duong, Tv.H., & Saadabadi, A. (Updated July 2022). Carbamazepine. In StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK482455/
  2. Weisler R.H. (2006). Carbamazepine Extended-Release Capsules in Bipolar Disorder. Neuropsychiatric Disease and Treatment, 2(1), 3-11. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2671727/
  3. The College of Psychiatric and Neurologic Pharmacists (CPNP) and the National Alliance on Mental Illness (NAMI). (Updated 2016). Carbamazepine (Tegretol). NAMI. Retrieved from https://www.nami.org/About-Mental-Illness/Treatments/Mental-Health-Medications/Types-of-Medication/Carbamazepine-Tegretol
  4. Validus Pharmaceuticals LLC. (Revised 2016). Equetro (Carbamazepine) Extended-Release Capsules. Access Data FDA. Retrieved from https://www.accessdata.fda.gov/drugsatfda_docs/label/2016/021710s11s012lbl.pdf
  5. Bertilsson, L. (1978). Clinical Pharmacokinetics of Carbamazepine. Clinical Pharmacokinetics, 3(2), 128–143. Retrieved from https://doi.org/10.2165/00003088-197803020-00003
  6. American Society of Health-System Pharmacists, Inc. (Revised 2020). Carbamazepine. MedlinePlus. Retrieved from https://medlineplus.gov/druginfo/meds/a682237.html
  7. Jallon, P., & Picard, F. (2001). Bodyweight Gain and Anticonvulsants: A Comparative Review. Drug Safety, 24(13), 969–978. Retrieved from https://doi.org/10.2165/00002018-200124130-00004
  8. Geddes, J.R., & Miklowitz, D.J. (2013). Treatment of Bipolar Disorder. Lancet (London, England), 381(9878), 1672–1682. Retrieved from https://doi.org/10.1016/S0140-6736(13)60857-0