SN instructed that the Lithium is used to treat the manic episodes of manic depression. Manic symptoms include hyperactivity, rushed speech, poor judgment, reduced need for sleep, aggression, and anger. It also helps to prevent or lessen the intensity of manic episodes. Drink extra fluids each day to keep from getting dehydrated while you are taking lithium. Tell your doctor if you have been sweating excessively, or if you are sick with fever, vomiting, or diarrhea for more than a few hours.