Illicit drug use: neurologic complications

John C M Brust MD (Dr. Brust of Columbia University College of Physicians and Surgeons has no relevant financial relationships to disclose.)
Matthew Lorincz MD PhD, editor. (Dr. Lorincz of the University of Michigan has no relevant financial relationships to disclose.)
Originally released October 8, 2008; last updated April 6, 2020; expires April 6, 2023

This article includes discussion of illicit drug use: neurologic complications, trauma, infection, seizures, stroke, and cognitive dysfunction. The foregoing terms may include synonyms, similar disorders, variations in usage, and abbreviations


The author describes the clinical features of intoxication and withdrawal of the major illicit drugs, as well as the neurologic complications often encountered in users, including seizures, stroke, and cognitive dysfunction. During 2019, the United States continued to experience an epidemic of opioid abuse as well as recreational use of synthetic cannabinoid agents marketed as “Spice” and “K2.”

Key points


• In addition to overdose, major complications of illicit drug use include trauma, infection, seizures, stroke, persistent cognitive impairment, and teratogenic effects.


• A seizure in an illicit drug user can have an indirect cause, such as cerebral contusion or CNS infection, or can be a manifestation of direct toxicity or withdrawal (eg, barbiturate).


• Evidence has increasingly demonstrated that a number of drugs can cause lasting neuropsychiatric impairment.

The content you are trying to view is available only to logged in, current MedLink Neurology subscribers.

If you are a subscriber, please log in.

If you are a former subscriber or have registered before, please log in first and then click select a Service Plan or contact Subscriber Services. Site license users, click the Site License Acces link on the Homepage at an authorized computer.

If you have never registered before, click Learn More about MedLink Neurology  or view available Service Plans.

Find out how you can join MedLink Neurology