I think there's a crossover between gambling and drug addiction but many things are really different too
with drugs the person usually has a good experience
with gambling the experience could be good or bad, but even with bad experiences the addicted gambler keep hooked to it and craving for more.
I think it is quite literally the same.
When gambling, the person does feel a "high" when winning. If the gambler only experiences losses, it is very unlikely they would come back. That's why casinos design their games so that you win some times, and lose some times (with more losing), so that your brain gets the dopamine release of the wins. That's the hook.
Similarly, drugs like alcohol produce a "high" while you keep sipping your beer. That's why you need to keep drinking as it's the increase of alcohol that makes you feel good.
the point is: when gambling you can get the high of winnings but you also get the "downs" of losing
sometimes losing can make you want to gamble again so you win
with drugs there's usually no instant "down", down comes later (as a hangover let's say)
I suspect they act on slightly different pathways in the brain but we'd have to investigate more to be sure
definitely and interesting subject.
Very interesting subject, but I think there is one major difference that goes a bit missing here and that is the influence of substances that have an unavoidable effect on hormonal balances in the body and specifically in the brain. Depending on the drugs you take, but especially chemical substances fuck the brain from all directions. Gambling is indeed slightly different in that you don't manipulate your hormonal balance through exogenous chemical shocks. You still have lots of excess cortisol when you lose or also are highly excited when winning, but it is still a different mechanism as no substance collides with the natural synthesis of hormones.