Problem gambling (ludomania) is an urge to gamble despite harmful negative consequences or a desire to stop. Problem gambling often is defined by whether harm is experienced by the gambler or others, rather than by the gambler’s behavior. Severe problem gambling may be diagnosed as clinical pathological gambling if the gambler meets certain criteria.

Although the term gambling addiction is common in the recovery movement pathological gambling is considered to be an impulse control disorder and is therefore not considered by the American Psychological Association to be an addiction.

According to the Illinois Institute for Addiction Recovery, recent evidence indicates that pathological gambling is an addiction similar to chemical addiction. It has been seen that some pathological gamblers have lower levels of norepinephrine than normal gamblers.

According to a study conducted by Alec Roy, M.D. formerly at the National Institute on Alcohol Abuse and Alcoholism, norepinephrine is secreted under stress, arousal, or thrill, so pathological gamblers gamble to make up for their under-dosage.

Further to this, according to a report from the Harvard Medical School Division on Addictions there was an experiment constructed where test subjects were presented with situations where they could win, lose or break even in a casino-like environment.