is a mood stabilizer which, like others in this class, was originally
developed to treat epilepsy. Carbamazepine is also beneficial for problems with
impulsivity and aggression (such as Intermittent Explosive Disorder). Although this medicine can be very
helpful, there are a few problems with carbamazepine
you need to be aware of:
Stevens-Johnson Syndrome: this serious rash, which appears as blistering in
the skin and mouth, is a rare side effect to carbamazepine
Drops in blood count: very rarely, carbamazepine
can cause serious drops in the blood cells necessary to fight infection and
Interactions with other medicines: carbamazepine can lower
the levels of many medications including contraceptives.
fetal defects have been associated with carbamazepine,
especially if taken during the first trimester.
the blood level of carbamazepine will need to be
monitored while you take it.
more information on these effects below.
How does it work?
Carbamazepine helps stabilize nerve cell firing.
What types are available and how is it taken?
Carbamazepine should be taken two to four times a day, with or
without food. This medicine is dosed by following the blood level, which
should be 8-12. Daily dose from 800 to
2400mg are usually needed to maintain a good blood level. After the first few months, carbamazepine levels frequently drop, so a dose
adjustment may be needed then.
If you miss a dose, ask yourself
if you are closer to the dose you missed or to your next dose. If you are closer to your next dose, just
wait and take it then, otherwise it’s ok to take the dose you missed.
Two companies have developed
extended-release versions which produce smoother blood levels and can be
taken less frequently (but still are recommended to take twice a day). If you are taking these capsules, do not
crush or chew them because that will break the coating.
Generic Tablets: 100 and 200mg. Liquid (25mg/ml).
60 tabs of: 100mg $13, 200mg $14. Liquid 450 ml: $28.
Carbamazepine XR (Tegretol XR)
Tablets: 100, 200 and 400mg.
30 tabs of: 100mg $10, 200mg $18, 400mg $35.
Carbamazepine XR (Carbatrol)
Tablets: 100, 200 and 300mg.
60 tabs of: 200mg $56, 300mg $53.
More about blood levels
Carbamazepine levels need to be checked a few times in the
beginning to determine your dose. The best time to have your level checked
is 12 hours after your last dose or just before your next dose. If you take
it all at night, have it checked in the morning. If you take carbamazepine in the morning, go to the lab before your
morning dose and then take that dose after your blood is drawn.
Once your dose is established,
your level should remain steady and can be checked every 6 months. Because
other medications can interact with carbamazepine,
we may need to check levels again if your start new medicines.
How long will I need to take it for?
symptoms have resolved, carbamazepine continues
to work to prevent future episodes of bipolar disorder. Going without it
can lead to more bipolar episodes, and after too many episodes your brain
can get in a habit (called “kindling”) of mood swings that is
harder to treat. Therefore, it is
best to take carbamazepine regularly as long as
side effects are not a problem. If it is ever stopped, it should be done
slowly to prevent a sudden return of symptoms.
What side effects can I expect?
Common side effects (many of these are worse at
Dizziness, vertigo or
“spinning” feeling, poor coordination, trouble walking, poor
concentration, fatigue, tremor, headache, changes in vision, double vision,
mild weight loss, nausea/vomiting, diarrhea, constipation, dry mouth,
stomach pain, indigestion, increased urination, muscle aches, depression.
Rare but serious side effects:
Stevens-Johnson Syndrome: a dangerous rash that appears as blistering of the
skin and mouth; this reaction is extremely rare.
Drops in blood count: including
platelets which are necessary for blood-clotting and white-blood cells which
are necessary to fight infection.
These occur in approximately 10 per million people per year who take
carbamazepine. To help reduce this risk, we will
monitor your blood count regularly.
Abdominal problems: abnormalities in liver function tests, blockage of liver ducts, pancreatitis.
Heart and lung problems: changes in blood pressure and in the heart’s
rhythms or pumping ability are very rare. A hypersensitivity reaction can
very rarely impair the lungs ability to breathe.
Low sodium (hyponatremia): symptoms of
low sodium include nausea, fatigue, headache, flu-like feelings, confusion
Eye problems: carbamazepine has been suspected in rare
cases of eye problems (deposits in the lens).
reaction is possible with any medication.
Symptoms include the following; stop the medication and call me if
Pounding heartbeat; swelling of the face, throat, tongue, lips, eyes,
hands, feet, ankles, or lower legs; hoarseness; difficulty swallowing or
breathing; hives; rash.
following are signs that your carbamazepine level
is too high:
or severe discoordination, confusion or loss of
consciousness, seizures, imbalance while walking, slurred speech, nausea
level can be dangerous. If you think your level is too high, do the
Stop carbamazepine, call your doctor or go to the emergency room.
Since carbamazepine may
cause drowsiness or discoordination, Make sure
you know how you react to it before you drive, use machines, or do anything
else that could be dangerous if you are not alert, well-coordinated, or
able to see well.
can reduce the effectiveness of oral-contraceptives.
is a category-D drug and should not be taken during pregnancy. Carbamazepine
is known to produce defects in human pregnancies. It does not have effects
on male sperm or female eggs, so will not affect pregnancy if the medicine
is stopped before conception.
Carbamazepine comes out in breast
milk. Talk to your doctor if you plan to breast-feed while taking it.
is considered safe in the treatment of epilepsy in children.
Older adults: Carbamazepine
may be removed from the body more slowly in people after age 65, so lower
dosages may be needed. .
Medical problems that can worsen with
illness (carbamazepine can lower T4 thyroid)
disease and high blood pressure
Carbamazepine has potentially
serious interactions with numerous medications, so consult your physician
before starting a new prescription or over-the-counter drug. Remember that carbamazepine
may make oral contraceptive pills ineffective. You can check some drug interactions at
the following site: Index of Drug Information.
out of the reach of children.
away from heat and direct light.
not store in the bathroom, near the kitchen sink, or in other damp
places. Heat or moisture may cause the medicine to break down.
not keep outdated medicine or medicine no longer needed. Be sure that
any discarded medicine is out of the reach of children.
Updated 9/18/4 by Chris Aiken,