I have been reading with great interest “Lost,” your excellent series on the opioid epidemic.

As a psychiatrist who works in a substance abuse program and prescribes Suboxone, I think the series is both timely and compelling. However, I have to take issue with some statements in the third installment, “Disease or bad behavior” (March 28).

Overall, the article makes the important point that the “moral” approach to addiction has failed, but you then quote two “experts” who take positions that contradict the evidence concerning addiction.

It is simply not true that (as you paraphrased psychology and addiction professor George Heyman) “addiction is voluntary and is driven by choices.” That may be true in the earliest stages of use, but once a person is addicted, they are taken over by the drug and no longer have voluntary choice.

It is also not true that “we are nowhere near being able to distinguish the brains of addicted persons from those of non-addicted individuals” (to quote the article by psychiatry professor Carl Hart that was referenced in your story). There is a wealth of evidence that addiction changes the brain in important ways that interfere with motivation, with impulse control and with executive function, the ability to plan and carry out actions. These changes have been carefully described by Nora Volkow, M.D., director of the National Institute on Drug Abuse, among others.

As you point out in the series, how we think about addiction has real-world consequences, both in terms of policy and in terms of the stigma that interferes with treatment. Your otherwise excellent article would have been even better without quoting these outlier “experts.”

David Moltz, M.D.

Portland