Side Effects of Carbamazepine

Type of Drug

Anticonvulsant; drug used to treat a variety of seizure disorders.

Analgesic (pain reliever) for certain types of nerve pain (eg, trigeminal neuralgia).

How the Carbamazepine Product Works

Carbamazepine appears to prevent or reduce the number of seizures by controlling the activity of nerve impulses in the central nervous system. In trigeminal neuralgia, carbamazepine may reduce the activity of nerve impulses in the trigeminal nerve (nerve to the face), decreasing pain transmission.

Uses of The Carbamazepine

To control partial seizures with complex symptoms (eg, psychomotor, temporal lobe), grand mal and mixed seizures, alone or with other anticonvulsant drugs.

To treat trigeminal neuralgia (tic douloureux), a condition causing severe, stabbing pain in the face. Carbamazepine is not a simple pain reliever and should not be used for the relief of minor aches and pains.

Unlabeled Uses: Occasionally doctors may prescribe carbamazepine for neurogenic diabetes insipidus; certain psychiatric disorders; restless leg syndrome; nonneuritic pain syndrome (eg, phantom limb pain); and alcohol, cocaine, and benzodiazepine withdrawal management.

Potentially fatal blood cell abnormalities have been reported rarely following treatment with carbamazepine. Early detection of blood changes is important since some abnormalities may be reversible.

Minor pain: Do not use carbamazepine to relieve minor aches and pains. Pregnancy: Reports suggest an association between use of anticonvulsant drugs by women with epilepsy and an increased number of birth defects in children born to these women. Other factors (eg, genetics or the epileptic condition) may also contribute to the higher incidence of birth defects. Most mothers receiving anticonvulsant medication during pregnancy deliver normal infants. Tests to detect defects should be considered a part of routine prenatal care in childbearing women receiving carbamazepine. Do not abruptly or suddenly discontinue anticonvulsant drugs used to prevent major seizures. This could result in the occurrence of seizures, oxygen deficiency in body tissues, and an increased risk to both the mother and the unborn child. In cases where seizures do not pose a serious threat, your doctor may recommend gradual discontinuation of anticonvulsants prior to and during pregnancy. It is not known whether even minor seizures constitute some risk to the developing embryo or fetus. Use only when clearly needed and when the potential benefits outweigh the potential hazards to the fetus.

Breastfeeding: Carbamazepine appears in breast milk. Consult your doctor before you begin breastfeeding.

Children: Use in children under 6 years of age should be directed by clinicians expert in treating seizure disorders (eg, a neurologist).

Elderly: Carbamazepine may be more likely to cause confusion or agitation in elderly patients than in younger patients. Use with caution.

Lab Tests: Lab tests may be required before and during treatment with carbamazepine. Tests may include: Complete blood counts, liver function tests, urinalysis, blood urea nitrogen, eye tests, thyroid tests, and carbamazepine blood levels. Carbamazepine may interfere with thyroid function tests and some pregnancy tests.

Drug Interactions

Tell your doctor or pharmacist if you are taking or if you are planning to take any over-the-counter or prescription medications or dietary supplements with carbamazepine. Doses of one or both drugs may need to be modified or a different drug may need to be prescribed. The following drugs and drug classes interact with carbamazepine.

• Acetaminophen (eg, tylenol)

• Alprazolam (xanax)

• Bupropinon HCI (wellbutrin)

• Cyclosporine (eg, neoral)

• Charcoal cimetidine (tagamet)

Side Effects

Every drug is capable of producing side effects. Many carbamazepine users experience no, or minor, side effects. The frequency and severity of side effects depend on many factors including dose, duration of therapy, and individual susceptibility. Possible side effects include:

Digestive Tract: Nausea; vomiting; stomach upset and pain; diarrhea; constipation; appetite loss; dry mouth or throat; sores on mouth and tongue; sore throat.

Nervous System: Drowsiness; dizziness; incoordination; headache; confusion; mood changes; behavior changes (especially in children); unusual body movements; slurred speech; hallucinations; depression; fatigue.

Circulatory System: Changes in blood pressure; changes in heart rhythm; blood disorder; decreased blood cell counts (eg, platelets, white blood cells); blood clots.

Respiratory System: Difficulty breathing; pneumonia.

Skin: Yellowing of skin or eyes; changes in pigmentation; easy bruising or bleeding; rash; hives; skin lesions; peeling; sensitivity to sunlight; sweating; hair loss.

Eyes or Ocular: Double vision; unusual eye movements; blurred vision; red, itchy eyes.

Urinary and Reproductive Tract: Changes in urinary frequency; urinary retention; kidney failure.

Other: Fainting; fever; chills; sore throat; aches in muscles and joints; leg cramps; swelling of legs or ankles; swollen glands; numbness or tingling in hands or feet; ringing in ears; abnormal sensitivity to sounds; altered liver and kidney function tests; altered thyroid function tests; decreased sexual ability; edema (fluid retention); hemorrhaging or bleeding; aggravation of lupus erythematosus; abnormal skin sensations.

Guidelines for Use

• Take as directed by your doctor. Daily dose varies depending on individual needs.

• May cause upset stomach. Take with food.

• Shake suspension well before using.

• Suspension should not be administered simultaneously with other liquid medicinal agents or diluents.

• Since the suspension produces higher blood levels than tablets, it is recommended that patients given the suspension be started on lower doses and increased slowly to avoid unwanted side effects.

• Do not use to treat ordinary types of aches or pain. This drug should be used only to treat pain of trigeminal neuralgia.

• Tegretol-XR tablets must be swallowed whole and never crushed or chewed. Tablets should be inspected for chips or cracks; damaged tablets should not be consumed. The tablet coating remains in the intestine and is excreted in the stool and may be noticeable.

• Carry Medic Alert identification indicating that you are using this drug.

• If you stop taking this drug suddenly, your convulsions may return. Do not stop taking this drug without talking to your doctor.

• If a dose is missed, take it as soon as possible. If several hours have passed or if it is nearing time for the next dose, do not double the dose in order to catch up (unless advised to do so by your doctor). If more than one dose is missed, or it is necessary to establish a new dosage schedule, contact your doctor or pharmacist.

• Stop taking MAG inhibitors at least 14 days before beginning taking carbamazepine.

• Notify your doctor if any of the following occurs: Unusual bleeding or bruising; yellowing of skin or eyes; stomach pain; pale stools; darkened urine; decreased sexual ability; confusion; dizziness; in coordination; hallucinations; excessive sedation; abnormal movements; mood changes; double vision; swelling; fever; chills; sore throat; ulcers in the mouth; rash.

• May cause drowsiness, dizziness, or blurred vision. Use caution when driving or performing other tasks requiring alertness, coordination, or physical dexterity until tolerance is determined.

• Absence (petit mal) seizures do not appear to be controlled by carbamazepine.

• Lab tests will be required before and during treatment, especially during the first 2 months, to make certain the drug is working properly and to screen for possible blood count disorders. Interference with some pregnancy tests had been reported. Be sure to keep appointments.

• Store Epitol tablets at room temperature in a tightly sealed, preferably glass container. Protect from moisture. Store Tegretol tablets and suspension at room temperature in a tightly sealed, light-resistant container. Protect from moisture.