Medications For Bipolar Disorder - Treating Depression: Depression

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Medications for bipolar disorder

Lithium is the most widely known medication used to treat bipolar disorder. Lithium helps stabilize moods. Other medications also have this effect — for example, some anticonvulsants (which are often used to combat seizures) also have mood-stabilizing properties. These mood stabilizers tend to be mainstays for treating bipolar disorder, but your doctor may recommend other medications as well. Depending on the nature of your illness, you may receive antipsychotic, antidepressant, or anti-anxiety medications.

Keep in mind that you may need to stay on some medication or combination of medications indefinitely to keep your mood stable. The likelihood of having a relapse when you go off medications is great, especially if you've had two or more episodes of mania or depression. Experts now believe that the more episodes of depression or mania you've experienced, the more intense and frequent your subsequent episodes may be. Therefore, for people with bipolar disorder, maintenance therapy is the best strategy.

Mood stabilizers

Stabilizing mood is the chief goal of any treatment for bipolar disorder. By preventing manic and depressive episodes, these medications smooth out the highs and lows of this illness.

Lithium. Lithium is one of the oldest drugs used in psychiatry. Since the 1960s, it has proved very effective in preventing the mood swings of bipolar illness.

Common side effects of lithium include thirst, nausea, and tremors. While this medication can alter laboratory measures of kidney, heart, or thyroid function, studies of people who have taken lithium for many years are reassuring. Significant damage to the kidneys is quite rare, and changes to the heart noted on electrocardiograms are almost always benign. Long-term lithium use can cause thyroid problems in up to half the people who use it, but these problems can be treated.

There is a narrow dose range in which lithium is effective. Since doses that are too high can rapidly become toxic, doctors use periodic blood tests to monitor lithium levels in people taking this drug. Dehydration and diuretics (which are taken for high blood pressure) can increase the concentration of lithium in the blood, making the risk of toxicity greater. Early symptoms of toxicity include diarrhea, vomiting, drowsiness, weakness, and loss of coordination. Without treatment, toxicity can lead to confusion, agitation, unstable blood pressure, stupor, or coma. But these problems are quite rare if you know the risk and your doctor monitors your blood levels regularly.

Because lithium takes days or weeks to become effective in someone who is going through a manic phase, doctors often prescribe additional medications to help in the meantime.

While lithium has some drawbacks, a survey conducted by two large health plans indicates that it's better at preventing suicide than valproate, a newer drug that is increasingly replacing it in the treatment of bipolar disorder (see below). According to research appearing in the Journal of the American Medical Association in 2003, patients taking valproate had a 70% greater risk of a serious suicide attempt and nearly three times the risk of death by suicide. The difference amounted to one completed suicide per 1,000 patients annually. Valproate is at least as effective as lithium for mania, but lithium provides better protection against depression, the state in which bipolar patients are most likely to commit suicide. Other research shows that when patients stop taking lithium, the suicide rate rises for several months, although the effect can be minimized by lowering the dose gradually.

Anticonvulsants. Anticonvulsant drugs are named for their ability to treat seizure disorders, but doctors have recognized their value in treating mania and stabilizing moods.

One such drug, valproate, is so effective that some doctors turn to it first when treating bipolar disorder. While it isn't more effective than lithium, some doctors and patients find that its side effects seem easier to tolerate, and the dose is easier to adjust. For most people, blood tests are needed less frequently, and it isn't as toxic as lithium in overdose. It also may be better for some types of bipolar disorder — for example, when a person has very frequent mood cycles. However, there is evidence that lithium is better than valproate at lowering the risk of suicide for people with bipolar disorder (see "Lithium").

Common side effects include nausea, sedation, and weight gain. People who have liver disease should not take valproate without having their liver function carefully monitored.

Other anticonvulsants, including carbamazepine (Tegretol), lamotrigine (Lamictal), topiramate (Topamax), and gabapentin (Neurontin), have also proved useful in treating some people with mood disorders. (For more on these medications, see Table 1.) In addition, doctors commonly combine different mood stabilizers to treat people whose episodes are not controlled by a single drug; for example, a person might take two anticonvulsants, or an anticonvulsant along with lithium.

Antipsychotics

Antipsychotic medications play a role in treating bipolar illness in one of two ways. An antipsychotic can be helpful if distorted or psychotic thinking occurs as part of an episode of mania. And even in the absence of a thought disorder, the addition of an antipsychotic may help if you've tried mood stabilizers alone without great success.

Risperidone (Risperdal), olanzapine (Zyprexa), and quetiapine (Seroquel) are among the antipsychotics most often chosen (see Table 1). A newer medication pairs olanzapine with the antidepressant fluoxetine (see below).

In some cases, the drug clozapine (Clozaril) is most helpful. But because it sometimes suppresses white blood cells that the body uses to fight infection, doctors offer clozapine only to people who haven't responded to other treatments.

Antidepressants

Because people with bipolar disorder are as likely to experience depression as mania, doctors may also prescribe antidepressants (see Table 1). One problem with using antidepressants to treat bipolar illness is that they can trigger a manic episode or cause a more rapid cycling of episodes. However, antidepressants can be helpful, and SSRIs and bupropion have been used safely for this purpose. Doctors have found that the mood stabilizer lamotrigine works well for people with bipolar disorder who are showing signs of depression. It tends not to cause the problems that antidepressants sometimes do.

A combination pill. A bipolar medication called Symbyax, introduced in early 2004, combines two medicines in one pill: the antidepressant fluoxetine and the antipsychotic drug olanzapine. The pill is touted as offering greater convenience, since some patients would have fewer pills to take. Plus, combining an antidepressant with an antipsychotic drug may be helpful for bipolar disorder, because antidepressants alone sometimes trigger mania in susceptible people. The addition of an antipsychotic drug can reduce that risk. However, some experts point out that this particular preparation has several drawbacks. Symbyax pills combine 6 milligrams (mg) or 12 mg of olanzapine with 25 mg or 50 mg of fluoxetine. These fixed amounts limit a doctor's ability to adjust the dose of each medication freely and make it harder to find the smallest effective dose for each drug. In addition, if a patient develops certain side effects, like weight gain or drowsiness, it won't be clear which drug is causing the problem. And since olanzapine alone comes in 5-mg doses and fluoxetine in 20-mg pills, it's not easy to convert to the combination pill after individual doses are established.

Finally, and perhaps most importantly, most patients who are treated for bipolar disorder aren't given these two medications in combination. In most cases, patients receive valproate or lithium alone. Then an antidepressant is added if those medications don't produce the desired effect. Combining an antidepressant with an antipsychotic is much less common.

Anti-anxiety medications

Doctors may also prescribe anti-anxiety medications to help with the jitteriness, racing thoughts, and overall worry and distress that often accompany manic episodes. Typical choices are either an SSRI, buspirone (BuSpar), or one of the benzodiazepines, such as alprazolam (Xanax), clonazepam (Klonopin), or lorazepam (Ativan). Each of these benzodiazepines may differ slightly in how quickly it is absorbed by the body and how long its effects last. For more information on these medications, see Table 1 and talk to your doctor.

Last updated:	January 23, 2007