Carbamazepine
Generic Name
Carbamazepine (car-bam-A-zuh-pene)
Brand Names
Atretol Tegretol
Carbatrol Tegretol-XR
Epitol Teril Equetro
Type of Drug
Anticonvulsant.
Prescribed For
Seizure disorders as well as other neuralgias; also severe pain; psychiatric disorders including depression, bipolar disorder, intermittent explosive disorder, borderline personality disorder, post-traumatic stress disorder, psychotic disorders, and schizophrenia; withdrawal from alcohol, cocaine, or benzodiazepine-type drugs; restless leg syndrome; hereditary and non-hereditary chorea in children; and diabetes insipidus.
General Information
Carbamazepine was first approved for relief of the severe pain of trigeminal neuralgia. Over the years, it has gained wide use in seizure control, especially in people whose seizures are uncontrolled with phenytoin, phenobarbital, or primidone, or who have suffered severe side effects from these drugs. Carbamazepine is not a simple pain reliever and should not be taken for everyday aches and pains. It is associated with potentially fatal side effects.
Cautions and Warnings
Carbamazepine should not be used if you are allergic or sensitive to any of its ingredients or to any tricyclic antidepressant.
Carbamazepine should not be used if you have had bone marrow depression.
Carbamazepine may cause severe, possibly life-threatening blood reactions. People who have had blood reactions to other drugs are at particular risk for another reaction with carbarnazepine. Your doctor should have a complete blood count done before you start taking this drug and repeat these tests weekly during the first 3 months of treatment, and then every month for the next 2-3 years. Unexplained fever or infection may be a sign of a blood reaction.
Monoamine oxidase inhibitor (MA01) antidepressants should be discontinued 2 weeks before starting carbamazepine.
Rarely, severe, possibly fatal skin reactions can develop in a few people taking carbamazepine. Asians are 10 times more likely to develop these reactions than non-Asians.
Carbamazepine may aggravate glaucoma and should be used with caution by people with this condition. This drug may activate underlying psychosis, and, in older adults, confusion or agitation.
This drug is not for the relief of minor aches or pains.
Possible Side Effects
V Most common: dizziness, drowsiness, unsteadiness, nausea, and vomiting. Other common side effects are blurred W double vision, confusion, hostility, headache, and severe water retention.
♦ Less common: mood and behavioral changes, especially in children. Hives, itching, rash, and other allergic reactions may also occur.
your breathing, speech,function, and many
Drug Interactions
• Carbamazepine blood levels may be increased by azoles (e.g. ketoconazole), acetazolamide, cimetidine, dalfopristin, danazol, delavirdine, diltiazem, haloperidol, isoniazid, propoxyphene, erythromycin-type antibiotics (except azithromycin), fluoxetine, fluvoxamine, loratadine, levetiracetam, macrolides, MAOls, nefazodone, niacinamide, nicotinamide, protease inhibitors, quinine, quinupristin, terfenadine, tricyclic antidepressants, valproate, verapamil, or zileuton, leading to possible carbamazepine toxicity.
• Carbamazepine may reduce the effectiveness of contraceptive drugs and cause breakthrough bleeding.
• Charcoal tablets or powder, clozapine, methsuximide phenobarbital and other barbiturates, phenytoin, primidone and theophylline may decrease the absorption of carbamazepine. Levels of phenobarbital, a breakdown product of primidone, may be increased by combining primidone and carbamazepine.
• Carbamazepine reduces the effects of acetaminophen, the anticoagulant (blood thinner) warfarin, and theophylline (prescribed for asthma). Increased dosage of these drugs may be necessary. Other drugs counteracted by carbamazepine are antipsychotics (e.g. aripiprazole, clozapine, olanzapine, quetiapine, risperidone, and ziprasidone), benzodiazepines (e.g. diazepam and lorazepam), bupropion, cyclosporine, digitalis drugs, doxycycline, felodipine, lamotrigine, levothyroxine, methadone, mirtazapine, certain muscle relaxants, oxcarbazepine, slatin drugs, tiagibine, topiramate, tramadol, and zonisamide.
• Combining carbamazepine and other antiseizure drugs, including felbamate, hydantoins, succinimides, and valproic acid, may cause unpredictable results. Combination treatments to control seizures must be customized to each person.
Possible Side Effects (continued)
♦ Rare: Rare side effects can affect
liver function, urinary other
parts of the body. Contact you you any side effect not listed above.
• Combining carbamazepine and lithium may increase nervous system side effectssuch as muscular twitching or im-
paired consciousness.
• Carbamazepine suspension should not be combined with
other liquid medicines or diluents.
Food Interactions
Take carbamazepine with food if it causes stomach upset. Avoid taking carbamazepine with grapefruit products.
Usual Dose
Adult and Child (age 13 and over): 400-1200 mg a day, depending on the condition. Usual maintenance dose is 400-800 mg a day in 2 divided doses.
Child (age 6-12): 200-1000 mg a day, or 22-24 mg per lb. of body weight 2-3 times a day for suspension or 4 times a day for tablets. Do not exceed 1000 mg a day.
Child (under age 6): 22-24 mg per lb. of body weight 2-3 times a day for suspension or 4 times a day for tablets; dosage should not exceed 77 mg per 1b. of body weight a day.
Dosage varies according to form. Liquid carbamazepine must be taken 3 times a day, regular carbamazepine tablets twice a day, and sustained-release tablets once daily. Never change your dosage schedule without first checking with your doctor.
Overdosage
Carbamazepine is a potentially lethal drug. Overdose symptoms appear in 1-3 hours. These include irregularity or difficulty in breathing, rapid heartbeat, changes in blood pressure, shock, loss of consciousness or coma, convulsions, muscle twitching, restlessness, uncontrolled body movements, drooping eyelids, psychotic mood changes, nausea, vomiting, and reduced urination. Induce vomiting right away with ipecac syrup—available at any pharmacy. Then take the victim to a hospital emergency room. ALWAYS bring the prescription bottle or container.
Mormation
Carbamazepine may cause dizziness and drowsiness. Take care while driving or doing any task that requires concentration.
Call your doctor at once if you experience yellowing of the skin or whites of the eyes, unusual bleeding or bruising, abdominal pain, pale stools, dark urine, impotence, mood changes, nervous system symptoms, swelling, fever, chills, sore throat, or mouth sores. These may be signs of a potentially fatal drug reaction.
If you forget a dose, skip it and go back to your regular schedule. it you miss more than I dose in a day, call your doctor. Do not stop taking this drug without first consulting your doctor.
Special Populations
Pregnancy/Breast-feeding: Carbamazepine caused birth defects in animal studies. Seizure disorder itself also increases the risk of birth defects. Pregnant women should take carbamazepine only after discussing with their doctors its potential benefits and risks.
Carbamazepine passes into breast milk. Nursing mothers who must take carbamazepine should use infant formula.
Seniors: Seniors taking this drug are more likely to develop heart Problems, confusion, or agitation.