Drug abuse still represents a significant challenge for forensic pathologists; it must always be considered during the autopsy examination when the brain morphological alterations observed are not characteristic of any known disease of the central nervous system (CNS). Nonetheless, no specific brain lesions had been found to characterize the precise drug that caused the poisoning. In fact, a broad spectrum of changes affecting the CNS are seen in drug abusers. Thus, forensic pathology plays a key role in identifying the encephalic morphological alterations underlying the death. The aim of this review is to present an updated overview of the literature regarding the correlation between the main substances of abuse and the morphological alterations of the CNS to help the forensic pathologist to discriminate drug-induced alterations of the brain. The authors used the PRISMA criteriology to perform the bibliographic search for the present review. Among the articles identified according to the selected search criteria, 116 articles were chosen which allow us to define a picture of the main macroscopic and microscopic alterations of the brain in drug abuse.
