can the use of heroin decrease the mass of the human brain?

Question by FORBIDDEN ADDICTION: can the use of heroin decrease the mass of the human brain?
i’m writing a book in which the character overdoeses on heroin. butat the smae times, he uses almost every drug. such as marijuana, cocaine, pills. if he shoots up four times a more a day how much will it decrease

Best answer:

Answer by NickyBoy
A local medical school or medical examiner might give you a leg up on this question.

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