A. Depression is more than the blues or the blahs; it is more than the normal, everyday ups and downs. When that "down" mood, along with other symptoms, lasts for more than a couple of weeks, the condition may be clinical depression. Clinical depression is a serious health problem that affects the total person. In addition to feelings, it can change behavior, physical health and appearance, academic performance, and the ability to handle everyday decisions and pressures.

Q. What causes clinical depression?

A. We do not yet know all the causes of depression, but there seems to be biological and emotional factors that may increase the likelihood that an individual will develop a depressive disorder. Research over the past decade strongly suggests a genetic link to depressive disorders, depression can run in families. Bad life experiences and certain personality patterns such as difficulty handling stress, low self-esteem, or extreme pessimism about the future can increase the chances of becoming depressed.

Q. How common is it?

A. Clinical depression is a lot more common than most people think. It affects 10 million Americans every year. One-fourth of all women and one-eighth of all men will suffer at least one episode or occurrence of depression during their lifetimes. Depression affects people of all ages but is less common for teenagers than for adults. Approximately 3 to 5 percent of the teen population experiences clinical depression every year. That means among 100 friends, 4 could be clinically depressed.

Q. Is it serious?

A. Depression can be very serious. It has been linked to poor school performance, truancy, alcohol and drug abuse, running away, and feelings of worthlessness and hopelessness. In the last 25 years, the rate of suicide among teenagers and young adults has increased dramatically. Suicide often is linked to depression.

Q. Are all depressive disorders alike?

A. There are various forms or types of depression. Some people experience only one episode of depression in their whole life, but many have several recurrences. Some depressive episodes begin suddenly for no apparent reason, while others can be associated with a life situation or stress. Sometimes people who are depressed cannot perform even the simplest daily activities - like getting out of bed or getting dressed; others go through the motions, but it is clear they are not acting or thinking as usual. Some people suffer from bipolar depression in which their moods cycle between two extremes - from the depths of despair to frenzied heights of activity or grandiose ideas about their own competence.

Q. Can it be treated?

A. Yes, depression is treatable. Between 80 and 90 percent of people with depression - even the most serious forms - can be helped. Symptoms can be relieved quickly with psychological therapies, medications, or a combination of both. The most important step toward treating depression - and sometimes the most difficult - is asking for help. Q. Why don't people get the help they need? A. Often people don't know they are depressed, so they don't ask for - or get - the right help. Teenagers and adults share a problem - they often fail to recognize the symptoms of depression in themselves or in people they care about