He cannot stay too long in gambling especially if he has lost in many times and I think it's better for him to get a rest for a while because playing gambling needs the stability of emotion. Many things he needs to do in gambling and he should prevent himself not to become addicted to gambling especially if his purposes are only for chasing the money and I guess that he will only get losing more money.
If a person play gambling regularly, I do not think that he will safe and will not become addicted in gambling.
May be some people whose reason of playing gambling is only to get fun and enjoyment. Their reason of playing gambling is not for making money, can prevent themselves from being addicted. Such people may have good control over their emotions, and that is the reason that never try to exceed their limit and they can even quit gambling at any time.