I get this question from patients often though it's usually stated more affirmatively: "I just have an addictive personality." Usually patients have been told this by physicians, therapists and family members, not to mention numerous media outlets that perpetuate the idea of an addictive personality. Even people who have not had serious problems with addiction wonder if they have an addictive personality. My usual question after someone asks me if they have an addictive personality is to say, "What do you mean when you say 'addictive personality'." The answers are usually pretty fuzzy but the idea seems to revolve around a feeling that one cannot delay gratification. Anything pleasurable is immediately seized upon as something that must be ingested, used, viewed, etc. without delay. I will then ask patients to describe what they have done over the past few days. Usually it doesn't take too long to pick out multiple choices they had to make in which gratification was delayed, at least temporarily. The point of this exercise is that when someone tries to explain their addiction by saying they have an addictive personality, my response is, "It ain't that simple."
The truth is that the "addictive personality" is a myth. In some ways, it's a fantasy because it attempts to explain all addictive behavior as essentially involuntary behavior. Thankfully, there are much more nuanced explanations of addictive illnesses, though none of them are complete. However, they all suggest that there are many ways that a person can develop an addictive illness. An article by Maia Szalavitz in a recent issue of Nature Outlook (a companion to the well-known scientific journal Nature) reviews some of these theories and is a good introduction to modern ideas about how addictive disorders develop.
Ms. Szalavitz notes that the idea of an addictive personality likely stems from research in the genetics of addictive illnesses. This research shows clearly that addiction is a highly heritable illness with estimates that genetics explain anywhere from 40-60% of the risk of developing an addictive illness. However, this means that about 40-60% of the illness is explained by other factors. Some of these factors include comorbid psychiatric illnesses (which are also, to some extent, genetically inherited), epigenetic factors and childhood abuse/trauma to name a few. To complicate the picture further, these different risk factors often interact with each other. For example, trauma can result in the activation of genes (epigenetics) that influence the production of proteins like the serotonin transporter which, in turn, affects the regulation of serotonin in the brain. Changing serotonin processing in the brain can then have an impact on mood regulation.
So, while we can't fall back on an addictive personality to explain addictive behavior, that's actually a good thing. It means that there are multiple "points of entry" for treating addictive illnesses including medication, behavioral therapies, family therapy, etc. While the knot of addictive illness may be difficult to untie, it is not the Gordian knot of an addictive personality.