Washington ? Amy Topel had tried exercise, weight-loss pills and every diet, real or fad, around. But at age 15, she’d reached 260 pounds and a difficult decision: It was time to try surgery.

Operating was scary, but her mother had undergone it and lost 100 pounds — and Amy was tired of classmates’ taunts. So in June, the same surgeon shrank Amy’s stomach. She’s dropped 30 pounds and counting.

Gastric bypass surgery has long been a dramatic solution for obese adults, but more doctors are operating on teenagers, too. Now the first pediatric guidelines are due out soon in the United States, and they’ll urge doctors to put more limits on teens’ surgery than on adults’ — because nobody yet knows the long-term outcomes of such a radical operation on a still-developing body.

The main recommendations:

• To qualify, teens should have obesity-caused problems, either physical or, like Amy, from the stigma of being fat — and a starting weight at least 30 pounds higher than adult candidates.
• Don’t operate before teens nearly reach their full height potential — usually around age 13 for girls and 15 for boys — because the surgery limits nutrient absorption.
• Hospitals should establish a panel of experts in adolescent obesity, psychology and nutrition to evaluate teens’ physical and psychological well-being and pick the best candidates.

Surgery clearly will help some teens, but “it made sense to all of us to set the bar a bit higher,” says Dr. Thomas Inge of the Cincinnati Children’s Hospital Medical Center, who co-authored the guidelines with fellow specialists in pediatric surgery and obesity.

Amy Topel, 16, has lost 30 pounds and counting since undergoing gastric bypass surgery.

The guidelines have been submitted to a medical journal for publication later this year, and promise to be somewhat controversial. Some surgeons say there’s no reason to be more cautious with teens. After all, heart disease, diabetes and other obesity-related illnesses can take root in childhood — and teens will have longer to reap the benefits of being slimmer.

“There’s no doubt surgery is a drastic measure. It is a risk to life. But at times, living with a condition like this obesity — it is a risk to life by itself,” says Dr. Constantine Frantzides of Rush-Presbyterian-St. Luke’s Medical Center in Chicago, who operated on Amy.

There are no statistics on how many teens get gastric bypass; the number is believed very small but growing.

The operation entails stapling closed part of the stomach, forming a small pouch that’s connected to one end of the small intestine. That limits how much food it’s possible to consume, and how much is absorbed. Typically, patients lose 70 percent to 80 percent of their excess body weight in about a year.

But the surgery itself comes with risks, such as wound infections, the possibility of stomach leaks, occasionally life-threatening blood clots.

Once patients recover, they must follow stringent rules: They eat small servings, carefully counting to get enough protein. They take vitamins and calcium to counter nutrient deficiencies, including bone loss.

Gorging causes vomiting. The body no longer processes sugar properly, so too much causes dizziness and diarrhea. Regularly breaking the rules can bring back the weight.

Such changes are hard enough for adults. So the pending pediatric guidelines stress having experts evaluate whether a teen is mature enough, and has stable family support, to follow the rules before surgery is offered.