Kemadrine (Procyclidine) Dosing
For adults, the standard dose of procyclidine (Kemadrine) is 2.5 mg three times daily initially, which can be increased gradually to a typical maintenance dose of 5 mg three times daily (15 mg/day total), with a maximum of 20-30 mg/day in divided doses if needed for control of extrapyramidal symptoms.
Standard Adult Dosing
- Initial dose: Start with 2.5 mg orally three times daily after meals 1
- Maintenance dose: Increase gradually to 5 mg three times daily (total 15 mg/day) based on response and tolerability 1
- Maximum dose: Can be increased up to 20-30 mg/day in divided doses if necessary for adequate control of parkinsonian symptoms 2, 1
Clinical Context
Procyclidine is an anticholinergic medication primarily used to manage extrapyramidal side effects (EPS) induced by antipsychotic medications 1. The drug effectively prevents and treats drug-induced parkinsonism, including rigidity, tremor, and akinesia 1.
Key Dosing Considerations
- Dose titration: Adjust the dose gradually based on individual response to minimize anticholinergic side effects while achieving adequate symptom control 1
- Timing: Administer doses after meals to reduce gastrointestinal side effects 1
- Prophylactic use: When used prophylactically in patients on long-term antipsychotic therapy, procyclidine significantly reduces the incidence of EPS (0% vs 54% with placebo) 1
Important Clinical Caveats
Cognitive Effects
- Higher doses impair information processing: Procyclidine at 15 mg single dose significantly impairs prepulse inhibition (a measure of early sensory processing) in both healthy volunteers and patients with schizophrenia, while 10 mg does not 3, 4
- Use minimum effective dose: Given the cognitive disruption at higher doses, maintain patients on the lowest dose that adequately controls EPS 3, 4
Withdrawal Considerations
- Do not abruptly discontinue: Sudden withdrawal in patients on chronic therapy results in EPS development in 54% of cases within three weeks, including akinesia in 27% 1
- Risk of misdiagnosis: Akinesia from procyclidine withdrawal can be mistaken for negative symptoms of schizophrenia or depression 1
Common Pitfalls to Avoid
- Avoid using standard doses in elderly patients: Older patients may require lower doses due to increased sensitivity to anticholinergic effects
- Monitor for anticholinergic toxicity: Watch for confusion, urinary retention, constipation, dry mouth, and blurred vision, especially at higher doses
- Consider abuse potential: Procyclidine has documented abuse potential in some populations and should be monitored accordingly 5