“Lack of dopamine” isn’t an accurate description. It’s a reductionist pop culture metaphor that feels scientific but it’s not really accurate. Drugs of abuse involve multiple systems including opioid receptors, which modulate reward. There is much more going on than simple levels of a single neurotransmitter, which can actually be completely normal relative to non-addicts. Dopaminergic systems are actually involved in driving certain addictive and craving mechanisms, which should be a hint that it’s not as simple as “lack of dopamine”.

In fact, the side effects of certain drugs that directly increase dopamine levels (L-DOPA) or drugs that directly stimulate dopamine receptors (dopamine agonists like bromocriptine) include a risk of compulsive gambling, shopping, and risky behaviors.

Ironically it’s more accurate to simply say “withdrawals” than to try to inject reductionist neurotransmitter speak.