Lisa took her overdose just after her 17th birthday. Her friends and family waited outside the intensive care unit, shocked, frightened and disbelieving.

Lisa appeared to be on top of the world. She had made the honor roll, was popular and dated frequently. No one would have predicted that she would take a massive overdose of Librium and alcohol, serious enough to require a respirator to keep her breathing while the drugs slowly left her body.

Her parents were bewildered and grief-stricken, realizing suddenly how little they knew about their daughter, the one they had been so proud of and on whom they had pinned so many hopes . . .

Area teen-agers are overdosing in increasing numbers with common household medications. They are not using the esoteric street drugs one hears about in the news. And unlike chronic drug-abusers, these teens are appearing more and more frequently in emergency rooms and psychiatric settings after overdosing on aspirin, Valium, barbiturates and alcohol.

These are not "bad" kids. Rather, they are "straight" teens who often have high standards and goals and a tradition of success in their family. Why are they lying comatose in a hospital?

Surprisingly, the very attributes that most of us admire often relate to the cause of the desperation in these teens, and the problem is much closer to home than one might think.

Although suicide is the third leading cause of death among adolescents, most attempts are not fatal. Nationally, statistics show that for every suicide among teen-age girls, there have been 50 attempts; for boys, 15-20. These nonfatal attempts may best be understood as an attempt to communicate a message, a dramatic cry for help or rescue.

But why? When you listen to their stories, some common reasons stand out.

One is a fear--common to all generations of teen-agers--of being excluded or rejected by others. This age-old fear is accentuated these days by a tremendous focus on sexual and social sophistication at an early age. Ads for the designer-jean generation tend to promote physical assets and beauty, making for painful self-awareness in those teens who have physical drawbacks.

In other adolescents the cry for help relates to pressures to succeed in areas other than appearance. There is scholastic pressure to be better than the average; pressure to excel athletically; pressure to become "somebody."

Where does the pressure come from? Certainly from within, but also from us. Many of the teen-agers who are overdosing come from homes where parents are high achievers. They might be very human in the eyes of their adult friends, but to their children they may seem nearly God-like in their perfection.

Many teen-agers from this kind of environment literally never have seen failure. In this context even mild failure can be experienced as a shattering and catastrophic experience.

In addition, the adolescent often is a poor judge of his or her performance. Already under strong biological pressures from pubertal changes, confused by a rapidly changing body image and struggling to make sense of a confusing future, they barely can keep their perspective. These pressures can become overwhelming and may lead to suicide in an attempt to escape unbearable feelings.

There appears to be a relationship between suicide and the pivotal period between adolescence and adulthood. Although today's teens in many ways appear more knowledgeable than previous generations, and are generally more physically mature and perhaps more perceptive, they may not be emotionally or experientially ready to handle this difficult transition.

Despite the strong influence of teen peer groups, there can be a paradoxical sense of aloneness. Groups may hang together acting cool and tough, while each teen-ager in the group may secretly feel that he is the only one hiding an insecurity.

Although most teens say they can't wait for their freedom, this often is false bravado. Many teens, in quieter, more trusting settings, will acknowledge how frightened they are of adulthood. Whereas grades may have been good or even exceptional in previous years, performance may begin to fall during the senior year as the conflict over growing up and becoming independent intensifies. Previous interests may give way to apathy and lethargy.

The cause of this mysterious decline may be a reluctance to accept the responsibilities of the next stage because of unrealistic fears of failure and humiliation. Teens who believe their parents have never failed may be particularly vulnerable. "If adults don't fail," their thinking goes, "then I must not be ready to be an adult."

A related theme among many teen-agers who attempt suicide is the fear of competition. These young people often experience competition as a life-or-death matter rather than as a socially approved means of promoting excellence. They feel guilty about their achievements and successes--considering them to be at the expense of others--and then begin to feel that competition and caring cannot coexist.

When competition for grades and college placement becomes more intense, these adolescents often begin to develop unrealistic fears that their competitive urges are destroying others.

Certain family difficulties also can contribute. Many teen-agers appear to have been driven to suicide because of divorce--particularly the more hostile, divisive and destructive divorces. At such times parents become excessively self-absorbed, and their children in turn feel victimized. Many feel that they are being placed in the middle of two raging forces, and believe they must choose one and sacrifice the other.

To add to the tragedy, parental divorce may come at a time when the turbulent psychological world within the adolescent, and the rapidly changing demands of the external world already create great stress. Divorce then destroys one part of the world that the teen had come to know as durable and stable. Thus if parents, those seemingly knowledgeable and strong adults, can't make a go of it, the adolescent begins to believe that there is little use in his trying.

Peer pressure, impending adulthood, affluence, parental success, broken homes and fears of competition all have been implicated in the growing dilemma that claims the lives of so many adolescents. Given all these causes there is no simple answer, but some general guidelines may help.

A large part of the problem is a sense of failure or fear of failure, either perceived or real. What may be a failure to one teen-ager is merely a disappointment to another, and may indeed be a success to a third.

One 17-year-old girl who took an overdose had received scores in the 50th percentile on her college-entry exams, which meant that there were as many below her as above. She was average in an already select group of college-bound teens. But because both parents and older siblings were highly successful, she felt like such a failure that she took an overdose, threatened to slash her wrists and was hospitalized.

Parents could help teens understand where failure fits in the scheme of life. Parents who present themselves as perfect, or all-knowing, unwittingly devalue and humiliate a child who may be filled with confusion and self-doubt. The parent who shows some humility, who can share some of his own failures as well as triumphs, is a strong aid in helping that child overcome his own sense of failure.

Talking with a grandparent about "the early years" is another way of helping put life into perspective. The grandparents of even the most affluent teens generally faced hardships with doubt and anxiety, yet are living proof that one can prevail.

Discussing life with those who are five or 10 years further along also may be of help; these young adults have fresh memories of their own fears and self-doubts, yet have crossed the threshold into adulthood.

Parents need to do some soul searching, to see whether they add to the internally experienced pressures in their teen-age children. To demand of children that they be more than they are is a setup for a profound sense of despair and low self-esteem.

Of course, children should be introduced to new ideas and skills, yet if they are pushed at the expense of what the child has already shown a real interest in, or has achieved, the child will learn to distrust his own inclinations.

In reality most teens don't want total freedom. What they really want (and need) is support, guidance and the right amount of "hands off." Parents can encourage signs of maturity by giving affection and praise when a teen-ager makes a good judgment in a certain area, thus increasing the likelihood of future mature judgments. To simply discourage signs of immaturity--although admittedly necessary at times--will only reinforce a cycle of negative behavior and failure.

Caroline, a spunky 16-year-old who was hospitalized after slashing her wrists was overheard saying, "I did it to get even with them. It was the only way I wanted to hurt them in return."

When Caroline's parents began to tell her of what they admired and valued in her, she began to cry, as did they, breaking a barrier and creating the beginning of a new relationship.

Some parents remember the way they hated discipline in their own parents, and they refrain from rules because they "love" their children, or because they want to avoid a fight. Often their offspring then develop the impression that their parents don't care about them, and aren't concerned about what they do or where they go. Discipline, when tempered with fairness, is one of the best ways parents can communicate their love.

When a parent shares both triumphs and failures, strengths and weaknesses, this validates for their adolescents that inner doubts and fears don't preclude moving on to a successful adulthood.

Lisa is alive now, and recently returned home after a three-month stay in the hospital. Her stay was punctuated with grief over what she had done, and rage at herself and her parents for the intense pressures under which she had lived for many years.

Her successes had come at a terrible price: the price of being "Miss Sunshine" for all of those around her. Her depression has not ended, and her recovery is far from complete, but she is very glad to be alive.

Bruce Kehr is a psychiatrist practicing in Rockville.