A person with bipolar disorder usually goes through spells of mania followed by spells of depression. These periods of happiness and sadness are not normal bouts of happiness and sadness that everyone experiences from time to time. Instead, these episodes are intense and may be categorized as severe mood swings. Symptoms of mania are associated with - rapid speech and thoughts, amplified energy, sleep deprivation, elevated mood and inflated confidence, increased physical and mental activity, unwarranted irritability, aggressive behavior, impatience and poor judgment, irresponsible behavior like over spending, making rash decisions, erratic driving, difficulty concentrating and an inflated sense of self-importance. Symptoms of depression are loss of interest in daily activities, long-drawn-out, sad or irritable moods, loss of energy or fatigue, feelings of guiltiness or worthlessness, sleeping too much or inability to sleep, drop in grades and inability to concentrate, inability to experience pleasure in anything, appetite loss or overeating, anger, worry, anxiety and thoughts of death or suicide.

In adults the phase of mania or depression can last for weeks or months. In children and adolescents, these episodes can be for a shorter period, and a child or teenager can n go back and forth between mania and depression throughout the day. Episodes of mania or depression may happen irregularly and follow a changeable pattern or they may be linked with a manic episode following a period of depression, or vice versa. For example, mania in the spring may be followed by depression in the winter.

Between episodes, a person with bipolar disorder frequently returns to normal functioning. In many people, although there is little or no break period between cycles, mood swing cycles change slowly or rapidly, with rapid cycling between mania and depression much more common in women, children and adolescents.

Some people with bipolar disorders resort to alcohol and drugs because they feel better when they're high. However, using alcohol and drugs can have disastrous results for people with bipolar disorders. Substance abuse can actually make the symptoms of bipolar disorder worse, making the condition hard for doctors to diagnose.