Substance abuse and movement disorders

Area of Science:

• Neurology
• Toxicology
• Substance Abuse Research

Background:

• Movement disorders are frequently linked to the use of ethanol, illicit drugs, and tobacco.
• Ethanol withdrawal can manifest as tremor, parkinsonism, chorea, and myoclonus.
• Substance abuse is a critical factor to consider in diagnosing unexplained movement disorders.

Purpose of the Study:

• To review the association between substance abuse and various movement disorders.
• To highlight the dual role of ethanol in exacerbating and ameliorating specific movement disorders.
• To emphasize the neurotoxic effects of certain illicit substances and the potential protective effects of tobacco.

Main Methods:

• Literature review of studies investigating substance abuse and movement disorders.
• Analysis of clinical presentations and neurological outcomes associated with different substances.
• Categorization of movement disorders based on causative agents (ethanol, opioids, psychostimulants, tobacco).

Main Results:

• Ethanol use is associated with withdrawal tremors, parkinsonism, chorea, myoclonus, and asterixis, but can also improve essential tremor and myoclonus-dystonia.
• Opioids like meperidine can cause myoclonus; contamination with MPTP led to severe parkinsonism.
• Heroin inhalation caused spongiform leukoencephalopathy, chorea, and myoclonus; psychostimulants like cocaine induce stereotypies and dyskinesias; phencyclidine causes myoclonus.
• Tobacco use appears to protect against Parkinson's disease.

Conclusions:

• Clinicians must consider substance abuse in patients presenting with unexplained movement disorders.
• The relationship between substance abuse and movement disorders is complex, with both detrimental and potentially beneficial effects observed.
• Understanding these associations is crucial for accurate diagnosis and patient management.