The dopamine system also responds robustly to addictive drugs, including opiates, alcohol and cocaine. These drugs can evoke stronger activation than natural rewards and, unlike natural rewards, they do not cause satiety.

A straightforward interpretation of these facts is that the dopamine system is a pleasure pathway in the brain.
One of the most important aspects of dopamine function is movement wich allows us to learn. Researchers believe that dopamine neurons change their activity when expectations about reward do not match the reality, signalling a ‘reward prediction error’ that drives learning. For instance, dopamine neurons are activated by unanticipated rewards, but they are suppressed when expected rewards fail to materialize.

Can brain research be used to overcome the effects of dopamine in addiction?

Neuroscientists are actively pursuing the creation of drugs that block the learning induced by dopamine in addiction. However, they have had limited success, for it is difficult to create a drug the blocks the learning without also blocking other functions of dopamine, such as feeling alert, motivated and happy.

Dopamine-induced learning is certainly not the whole story behind addiction, but it does suggest that we should consider whether addiction is something that human reasoning on its own can overcome. The same might very well also apply to other everyday failures of willpower, such as overeating.

Source & further reading:
https://medicalxpress.com/news/2015-12-dopamine-blame-addictions.html