Although lithium takes several weeks to start working, its success rate is about 70 percent and 20 percent of patients are completely freed of their symptoms. Patients generally require long-term maintenance treatment, and because lithium can be toxic it must be used carefully. Chronic use may endanger the heart, kidneys, and thyroid gland. Usually the dose is gradually increased until the drug begins to work and then periodically readjusted according to the patient's age, medical condition, and psychiatric symptoms. The amount of lithium in the blood must be checked regularly because it is ineffective if too low and risky if too high.
Some side effects are weight gain, hand tremors, drowsiness, and excessive thirst or urination.
Patients often cannot tolerate lithium either because of the side effects or because it takes some of the joy from their lives along with the manic episodes. Only 20 percent of patients with bipolar disorder take lithium alone. My symptoms are dynamic and occur in clusters of changing intensity. Sometimes mania dominates, sometimes depression, and I have no way of knowing which it will be or for how long. In my manic periods, I feel as though I am flying, gliding effortlessly through the day with an ever-increasing sense of wonderment and delight.