MEDICATIONS: ANTIMANIC MEDICATIONS
Bipolar disorder is characterized by cycling mood changes: severe highs
(mania) and lows (depression). Episodes may be predominantly manic or
depressive, with normal mood between episodes. Mood swings may follow each other
very closely, within days (rapid cycling) or may be separated by months to
years. The "highs" and "lows" may vary in intensity and severity and can
co-exist in "mixed" episodes.
When people are in a manic "high," they may be overactive, overly talkative,
have a great deal of energy and have much less need for sleep than normal. They
may switch quickly from one topic to another, as if they cannot get their
thoughts out fast enough. Their attention span is often short, and they can be
easily distracted. Sometimes people who are "high" are irritable or angry and
have false or inflated ideas about their position or importance in the world.
They may be very elated, and full of grand schemes that might range from
business deals to romantic sprees. Often, they show poor judgment in these
ventures. Mania, untreated, may worsen to a psychotic state.
In a depressive cycle the person may have a "low" mood with difficulty
concentrating; lack of energy, with slowed thinking and movements; changes in
eating and sleeping patterns (usually increases of both in bipolar depression);
feelings of hopelessness, helplessness, sadness, worthlessness and guilt; and,
sometimes, thoughts of suicide.
Lithium
The medication used most often to treat bipolar disorder is lithium. Lithium
evens out mood swings in both directions — from mania to depression, and
depression to mania — so it is used not just for manic attacks or flare-ups of
the illness but also as an ongoing maintenance treatment for bipolar disorder.
Although lithium will reduce severe manic symptoms in about five to 14 days,
it may be weeks to several months before the condition is fully controlled.
Antipsychotic medications are sometimes used in the first several days of
treatment to control manic symptoms until the lithium begins to take effect.
Antidepressants may be added to lithium during the depressive phase of bipolar
disorder. If given in the absence of lithium or another mood stabilizer,
antidepressants may provoke a switch into mania in people with bipolar disorder.
A person may have one episode of bipolar disorder and never have another, or
be free of illness for several years. But for those who have more than one manic
episode, doctors usually give serious consideration to maintenance (continuing)
treatment with lithium.
Some people respond well to maintenance treatment and have no further
episodes. Others may have moderate mood swings that lessen as treatment
continues, or have less frequent or less severe episodes. Unfortunately, some
people with bipolar disorder may not be helped at all by lithium. Response to
treatment with lithium varies, and it cannot be determined beforehand who will
or will not respond to treatment.
Regular blood tests are an important part of treatment with lithium. If too
little is taken, lithium will not be effective. If too much is taken, a variety
of side effects may occur. The range between an effective dose and a toxic one
is small. Blood lithium levels are checked at the beginning of treatment to
determine the best lithium dosage. Once a person is stable and on a maintenance
dosage, the lithium level should be checked every few months. How much lithium
people need to take may vary over time, depending on how ill they are, their
body chemistry and their physical condition.
Side Effects of Lithium When people first take lithium, they may
experience side effects such as drowsiness, weakness, nausea, fatigue, hand
tremor or increased thirst and urination. Some may disappear or decrease
quickly, although hand tremor may persist. Weight gain may occur. Dieting will
help, but crash diets should be avoided because they may raise or lower the
lithium level. Drinking low-calorie or no-calorie beverages, especially water,
will help keep weight down. Kidney changes — increased urination and, in
children, enuresis (bed wetting) — may develop during treatment. These changes
are generally manageable and are reduced by lowering the dosage. Because lithium
may cause the thyroid gland to become underactive (hypothyroidism) or sometimes
enlarged (goiter), thyroid function monitoring is a part of the therapy. To
restore normal thyroid function, thyroid hormone may be given along with
lithium.
Because of possible complications, doctors either may not recommend lithium
or may prescribe it with caution when a person has thyroid, kidney or heart
disorders, epilepsy or brain damage. Women of childbearing age should be aware
that lithium increases the risk of congenital malformations in babies. Special
caution should be taken during the first three months of pregnancy.
Anything that lowers the level of sodium in the body — reduced intake of
table salt, a switch to a low-salt diet, heavy sweating from an unusual amount
of exercise or a very hot climate, fever, vomiting or diarrhea — may cause a
lithium buildup and lead to toxicity. It is important to be aware of conditions
that lower sodium or cause dehydration and to tell the doctor if any of these
conditions are present so the dose can be changed.
Lithium, when combined with certain other medications, can have unwanted
effects. Some diuretics — substances that remove water from the body — increase
the level of lithium and can cause toxicity. Other diuretics, like coffee and
tea, can lower the level of lithium. Signs of lithium toxicity may include
nausea, vomiting, drowsiness, mental dullness, slurred speech, blurred vision,
confusion, dizziness, muscle twitching, irregular heartbeat and, ultimately,
seizures. A lithium overdose can be life-threatening. People who are taking
lithium should tell every doctor who is treating them, including dentists, about
all medications they are taking.
With regular monitoring, lithium is a safe and effective drug that enables
many people, who otherwise would suffer from incapacitating mood swings, to lead
normal lives.
Anticonvulsants
Some people with symptoms of mania who do not benefit from or would prefer to
avoid lithium have been found to respond to anticonvulsant medications commonly
prescribed to treat seizures.
The anticonvulsant valproic acid (Depakote, divalproex sodium) is the main
alternative therapy for bipolar disorder. It is as effective in
non-rapid-cycling bipolar disorder as lithium and appears to be superior to
lithium in rapid-cycling bipolar disorder. Although valproic acid can cause
gastrointestinal side effects, the incidence is low. Other adverse effects
occasionally reported are headache, double vision, dizziness, anxiety or
confusion. Because in some cases valproic acid has caused liver dysfunction,
liver function tests should be performed before therapy and at frequent
intervals thereafter, particularly during the first six months of therapy.
Studies conducted in Finland in patients with epilepsy have shown that
valproic acid may increase testosterone levels in teenage girls and produce
polycystic ovary syndrome (POS) in women who began taking the medication before
age 20. POS can cause obesity, hirsutism (body hair) and amenorrhea. Therefore,
young female patients should be monitored carefully by a doctor.
Other anticonvulsants used for bipolar disorder include carbamazepine
(Tegretol), lamotrigine (Lamictal), gabapentin (Neurontin) and topiramate
(Topamax). The evidence for anticonvulsant effectiveness is stronger for acute
mania than for long-term maintenance of bipolar disorder. Some studies suggest
particular efficacy of lamotrigine in bipolar depression. At present, the lack
of formal FDA approval of anticonvulsants other than valproic acid for bipolar
disorder may limit insurance coverage for these medications.
Most people who have bipolar disorder take more than one medication. Along
with the mood stabilizer — lithium and/or an anticonvulsant — they may take a
medication for accompanying agitation, anxiety, insomnia or depression. It is
important to continue taking the mood stabilizer when taking an antidepressant
because research has shown that treatment with an antidepressant alone increases
the risk that the patient will switch to mania or hypomania, or develop rapid
cycling. Sometimes, when a bipolar patient is not responsive to other
medications, an atypical antipsychotic medication is prescribed. Finding the
best possible medication, or combination of medications, is of utmost importance
to the patient and requires close monitoring by a doctor and strict adherence to
the recommended treatment regimen.
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