What is lithium?

Lithium carbonate--a salt--came to be regularly used to control manic depression in this country in the 1960's. Today it is the most commonly used medication to treat bipolar disorder (manic depression). There are a variety of different brands of lithium dispensed in tablets, capsules, and liquid form: Cibalith-S, Eskalith, Lithane, Lithobid, Lithonate, and Lithotabs. Lithium is helpful in 70 percent to 80 percent of people with bipolar disorder, making it one of the most effective psychiatric medications available.

What does lithium treat?

Lithium has been most frequently and effectively used to control and prevent manic episodes in persons with bipolar disorder. Lithium has been successful in treating depression as well. In fact, the occurrence of depression in a person who has been taking lithium is often an indication that a higher dose is needed. In some cases, lithium is even a successful treatment for those with unipolar depression, or those who have never had a manic episode. Individuals who respond to lithium for depression are often those who have not responded to tricyclic antidepressants after several weeks of treatment. When given lithium in addition to their antidepressants, some of these people have shown significant improvement.

Lithium has also successfully treated schizophrenia in cases where there is a schizophrenic thought disorder accompanied by a change in mood that mimics either mania or depression. The similarity between people with this type of schizophrenia and those diagnosed with manic depression is their affective disorder--that is, the experience of strong emotions not related to what is happening in the environment. People with schizophrenia not experiencing an affective disorder will not likely respond to the combination of lithium and antipsychotic medication.

How long does lithium take to work?

For lithium to reach its maximum effectiveness, two or even three weeks is often required. To control severe mania, doctors often will prescribe an antipsychotic such as Haldol while waiting for lithium to take affect. When the manic symptoms disappear, the antipsychotic will usually be discontinued, but the lithium continued.

Physicians using combinations of lithium and antipsychotics are urged to closely monitor patients because of the danger of a toxic reaction to the combination of lithium and Haldol.

Some people on lithium report having breakthrough depression. These individuals may respond to an increase in the dosage or the addition of an antidepressant. When depressions occur in those who have been taking lithium and who are able to tolerate a higher dose, it is possible that the dosage has been inadequate.

What are the side effects of lithium?

Common side effects of lithium include nausea, loss of appetite, and mild diarrhea. These usually will taper off after the first few weeks. Dizziness and hand tremors have also been reported, and tremors can be diminished effectively if the dosage of lithium is gradually decreased. Medications that control tremors are Cogentin and Inderal. With Inderal, however, there may be a lowering of the patient's blood pressure and heart rate, and sudden discontinuation can cause anxiety and tremulousness.

Increased production of urine and excessive thirst are two common side effects that are usually not serious problems, but patients with kidney disease should not be given lithium. Midamor is a drug that can reduce urinating. Taking the day's dosage of lithium at bedtime also seems to help with the problem of increased urination. Other side effects of lithium include weight gain, hypothyroidism, increased white blood cell count, skin rashes, and birth defects.

People who are taking lithium should consult their doctor before taking the following: Ibuprofen (Advil), acetazolamide, antihypertensives, anti-inflammatory drugs, calcium channel blockers, carbamazepine, diuretics, hydroxyzine, inderal, procardia, marijuana, muscle relaxants, neuroleptics, table salt, baking powder, tetracycline, tricyclic antidepressants, MAO inhibitors, or caffeine.

While on lithium, a patient's blood level must be closely monitored. If the blood level of lithium is too low, the patient's symptoms will not be relieved. If the blood level of lithium is too high, there is a danger of a toxic reaction.

Are there specific concerns about lithium and pregnancy?

A study was done in 1992 to measure the effect of lithium on unborn babies. It was found that exposure to lithium during the first trimester of pregnancy might be associated with the increased risk of Ebstein's anomaly, a rare cardiac malformation. Otherwise, the rate of congenital malformations did not differ between the group that took lithium and the control group. Birthweight, however, was found to be significantly higher in the lithium group, despite the high percentage of lithium users who were also cigarette smokers (almost twice as many as the control group).

Reviewed by Robert Prein, MD of the National Institute of Mental Health, Rockville, MD