Dextromethorphan Induced Dystonia: A Rare Case Report.

Area of Science:

• Pharmacology
• Neurology
• Clinical Medicine

Background:

• Dextromethorphan is a widely used antitussive agent, derived from morphine, typically with minimal central nervous system (CNS) effects at therapeutic doses.
• It is prescribed for various respiratory conditions, from the common cold to severe acute respiratory illness (SARI).

Observation:

• A case report details a 64-year-old female with significant comorbidities (ischemic heart disease, heart failure with reduced ejection fraction, diabetes, hypertension, chronic kidney disease, hypothyroidism) who developed extrapyramidal symptoms.
• These symptoms occurred after administration of dextromethorphan at a therapeutic dose.

Findings:

• Literature review indicates only four prior case reports of dextromethorphan-induced dystonia, all involving accidental or intentional overdose in substance abuse disorder.
• This case is unique as it describes CNS side effects, specifically extrapyramidal symptoms, in an adult patient using dextromethorphan at a prescribed dosage.

Implications:

• This case underscores the potential for rare, serious CNS side effects like dystonia from therapeutic dextromethorphan doses, particularly in elderly patients with multiple underlying health conditions.
• Clinicians should be aware of this rare but serious adverse event, prompting careful consideration of dextromethorphan use in vulnerable patient populations.