It was once considered a moral failing. But the American Psychiatric Association classifies pathological gambling not as an addiction but as an "impulse control" disorder like pyromania. To be considered pathological, a person must demonstrate five or more of these 10 characteristics:
http://www.usnews.com/usnews/biztech/articles/050523/23patho.b.htm
1 Is preoccupied with gambling, reliving gambling experiences, or thinking of ways to get money to gamble.
2 Needs to gamble with a larger pot of money in order to achieve the desired level of excitement.
3 Tries repeatedly but fails to control, cut back, or stop gambling.
4 Becomes restless or irritable when attempting to scale back or stop gambling.
5 Gambles as a way to escape from family or work problems or to relieve a depressed or unhappy mood.
6 After losing money, often returns another day to get even.
7 Lies to family members, therapists, colleagues, or others to conceal the extent of the gambling habit.
8 Has committed illegal acts like forgery, fraud, theft, or embezzlement to finance gambling habit.
9 Has jeopardized or lost a significant relationship, job, or educational or career opportunity because of the need to gamble.
10 Borrows money from friends, family, even strangers to pay off catastrophic debts from gambling.
http://www.usnews.com/usnews/biztech/articles/050523/23patho.b.htm
1 Is preoccupied with gambling, reliving gambling experiences, or thinking of ways to get money to gamble.
2 Needs to gamble with a larger pot of money in order to achieve the desired level of excitement.
3 Tries repeatedly but fails to control, cut back, or stop gambling.
4 Becomes restless or irritable when attempting to scale back or stop gambling.
5 Gambles as a way to escape from family or work problems or to relieve a depressed or unhappy mood.
6 After losing money, often returns another day to get even.
7 Lies to family members, therapists, colleagues, or others to conceal the extent of the gambling habit.
8 Has committed illegal acts like forgery, fraud, theft, or embezzlement to finance gambling habit.
9 Has jeopardized or lost a significant relationship, job, or educational or career opportunity because of the need to gamble.
10 Borrows money from friends, family, even strangers to pay off catastrophic debts from gambling.