Treatment of Extrapyramidal Symptoms (EPS)
Anticholinergic medications are the first-line treatment for extrapyramidal symptoms, with benztropine 1-4 mg daily being the most effective option for acute drug-induced EPS. 1
First-Line Treatments Based on EPS Type
Acute Dystonia
- Administer benztropine 1-2 mg orally or parenterally, which usually provides quick relief 1
- Continue with benztropine 1-2 mg twice daily to prevent recurrence 1
- For severe or life-threatening dystonic reactions (such as laryngeal dystonia), parenteral administration is preferred for rapid response 1, 2
Drug-Induced Parkinsonism
- Start benztropine 1-2 mg orally 2-3 times daily 1
- Dosage must be individualized according to patient needs, with a maximum of 6 mg daily 1
- After 1-2 weeks, attempt to withdraw the medication to determine continued need 1, 3
Akathisia
- Consider beta-blockers (particularly propranolol) as they appear most effective for akathisia 2
- Benzodiazepines may be used as an alternative 2
- Anticholinergics like benztropine may be less effective for akathisia but can still be tried 2
Alternative Approaches
Medication Adjustments
- Reduce the dose of the offending antipsychotic if clinically appropriate 2
- Consider switching to an atypical antipsychotic with lower EPS risk (such as olanzapine, quetiapine, or clozapine) 4, 2
- Avoid high doses of even atypical antipsychotics, as they can still cause EPS at higher doses 3
Alternative Medications
- Amantadine can be used as an alternative to anticholinergics for drug-induced parkinsonism 2
- For akathisia resistant to first-line treatments, consider adding a benzodiazepine 2
Special Considerations
Duration of Treatment
- For acute dystonic reactions, continue treatment for at least 1-2 weeks after the initial episode 1
- For drug-induced parkinsonism, attempt to withdraw anticholinergic medication after 2 weeks to determine continued need 1, 3
- Long-term use of anticholinergic medications is not recommended unless symptoms recur upon withdrawal 3
Prevention Strategies
- Prophylactic anticholinergic treatment should be considered only for high-risk patients (young males, those with previous EPS) 3, 2
- If prophylactic treatment is initiated, it should be discontinued after at least two weeks 3
- Use the lowest effective dose of antipsychotics to minimize EPS risk 4, 2
Monitoring
- Regularly assess for early signs of EPS to allow prompt intervention 4
- Monitor for anticholinergic side effects (dry mouth, blurred vision, constipation, urinary retention) 1
Pitfalls to Avoid
- Do not continue anticholinergic medications indefinitely without attempting withdrawal, as long-term use adds unnecessary side effect burden 3
- Avoid routine prophylactic use of anticholinergics for all patients on antipsychotics 3
- Don't overlook that even atypical antipsychotics can cause EPS, especially at higher doses 3, 5
- Never misinterpret akathisia as anxiety or psychotic agitation, as this can lead to inappropriate treatment 4