Fueled by popular televised tournaments and easy access to online gaming sites, college gambling is on a hot streak.
More and more college students have turned to card games like Texas Hold 'Em and Black Jack to get their thrills.
Ryan, a college student who asked that his last name not be used, settled into a routine during his sophomore year. For several hours every night, he'd be on his computer playing online poker.
"I would pretty much get home from whatever I was doing at 10 at night, play until five in the morning," he said. "I had stopped doing everything and probably gained like 40 pounds."
And he lost as much as $25,000 in a single night. Eventually, his parents pulled him out of the University of Delaware.
"The way it has driven my life for the last three years, [gambling] is something I could never have seen myself doing," Ryan said.
He's now saddled with a $10,000 debt.
"Two clicks and no matter when or where, as long as you have a computer, you can be playing for however little or how much money you want," Ryan said.
A recent study by the Annenberg Public Policy Center found that monthly card-game gambling among young people was up 20 percent from the year before, and 57 percent of the young men surveyed said they gambled at least once a month.
These days, it's just as easy to gamble online as it is in the dorm.
Experts said as many as half a million students could be addicted to gambling. But schools are just beginning to recognize the severity of the problem.
"About one college student in 20 has a gambling problem, but it's an issue that's very much under the radar," Jeff Marotta, problem-gambling services manager for the Oregon state human resources agency, said in a statement announcing a campaign to help prevent college gambling. "Most colleges seem to view student gambling as a harmless extracurricular activity, yet we know that for a certain percentage of student gamblers it can lead to serious problems."
The gambling problem skyrocketed after the poker craze spawned hundreds of online gambling sites, experts say.
"You could figure out which ones were drunk, and the school would be concerned and they would want them to get treatment or whatever," said George Meldrum, at the Delaware Council on Gambling Problems. "But the kid who is gambling in his dorm room, at his computer, no one is seeing that."
Ryan's problem was caught because his credit card company called his parents.
"I know how easy I could be back there," he said.
He still gambles online a few hours a week and struggles to keep it under control.
Younger children are at risk as well. A survey of adolescents found that more than 80 percent of those between the ages of 12 and 17 said they gambled in the last 12 months. More than 35 percent said they gambled at least once a week.
As with any addictive behavior, there are often clear signs of a developing problem. Individually, these signals may not indicate a problem. If you even suspect that there might be one, though, a professional evaluation is recommended.
Here are signs to look for if you believe someone you know has a gambling problem:
- Unexplained need for money
- Money or possessions missing from the home
- Unexplained charges on credit card bills
- Withdrawal from friends and family
- Missing school or classes
- Frequent anxiety, depression or mood swings
- Dropping outside activities and interests
- Excessive watching of TV sports
ABC News' John Yang contributed to this report.