There are some patients at the Bangor teen health clinic who seem to embody the worst of all the problems that adolescents face these days.

You could start with the 16-year-old girl from the foster-care system who gets drunk four days a week and sniffs “white-out” in order to suppress her confused feelings about life and where she fits in.

Then there’s the youngster from the sticks whose learning problems in school may stem from having to live with a mother and stepfather who are alcoholics. The boy can’t even escape the domestic turmoil by playing sports after school, because he has no way to get home.

Another teen-ager arrives at the clinic suffering from severe anxiety, fatigue, and weight loss because the most important people in her life have been dying around her.

Most teen-agers will navigate the sometimes troubled seas of adolescence with only the standard crisis or two. Others, whether living in the streets or in homes where parents ignore or abuse them, are potential shipwrecks. Without guidance, their chances of reaching adulthood unscathed are not good.

Dr. Bruce Brown, a Bangor pediatrician who specializes in adolescent medicine, estimates that the teen-age population he sees is split evenly between those who are faring well and those with chronic health problems. Since opening his Teen/Young Adult Clinic at Eastern Maine Medical Center in May, Brown has been visited by youngsters contemplating suicide to those who simply need a physical exam for sports.

Their medical needs and backgrounds may vary greatly, but each shares the traits and special concerns common to all adolescents. At a time when youngsters may be experimenting with drugs, alcohol, or sex, when they are testing social boundaries and learning what’s acceptable and what isn’t, the absence of routine

medical care can allow treatable problems to go unchecked.

Yet 10 to 25 percent of teen-agers have not received any medical care in the last year, Brown said. Those statistics might lead adults to assume wrongly that teen-agers are always healthy in body and mind.

“We know there are kids out there who need some source of medical care, and we hope to tell them that there is something available to them,” Brown said.

Confidentiality, Brown said, is the password to an adolescent’s life. Teen-agers find no crying babies in the clinic’s waiting room — no one but teens like themselves who share similar difficulties.

“It is encouraging to find, too, that even kids who people would call dysfunctional have parents who care enough about them to come in with them,” Brown said. “That was the surprise for us, finding that not as many parents have given up on the kids as we might think.”

The bad news, he said, is hearing too often from troubled teen-agers that they feel powerless to change the course of their lives.

“They think they have to continue doing what they’re doing, whether it’s being with an abusive boyfriend, distrusting all adults, or drinking excessively every Saturday night,” Brown said. “I am deeply disturbed about all the drinking I hear about from the kids. It’s hard for me, knowing all the choices they have, to hear them profess not to know any other routes to take.”

Despite all the education campaigns aimed at teen-agers about AIDS in the last several years, Brown said he does not get the sense that teens are afraid of the disease.

“There are so many fingers being shaken at kids these days, telling them not to do this or don’t do that,” Brown said. “The kid figures that you’ve got to be kidding, that the world couldn’t be that dangerous.”

After talking with youngsters at the clinic and in the homeless program called Project Streetlight, Brown is convinced that Maine adults must “disabuse themselves of the notion that kids here are not as at risk as the kids on the streets of Boston.”

While there may be less crack and fewer intravenous drugs used in Bangor than in a large city, he said, the mental-health consequences of being on the streets here, even temporarily, are equally significant.

“You could say that 100 percent of kids on the streets are depressed,” he said. “That’s natural. They have to make significant compromises in order to get shelter and food out there. They make compromises with their hygiene. One homeless kid said to me that the reason he didn’t go to school was not because he didn’t want to, but because he smelled.”

Brown said it often takes greater courage to leave the streets than to remain, considering the “systematic abuse” and “chaotic conditions” that many youngsters must return to at home.

Not all the news is bad, he said, despite the “myriad” problems of drugs, alcohol, AIDS, sexually transmitted diseases, divorce, and depression that teen-agers face. Brown is encouraged, for instance, to hear many of them say they have never used drugs before, and have no intention of starting.

“Some kids come in with a pain, and if we pass the test they might throw us the curve ball and let us know about deeper problems in their lives,” he said. “But many of the kids have no hidden agenda, and I can congratulate them on the choices they have made so far.”