Apomorphine (Apokyn) is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Apomorphine is a non-selective dopamine agonist with potent D1 and D2 receptor activity, administered subcutaneously for the treatment of advanced Parkinson's disease. Unlike oral dopamine agonists, apomorphine provides rapid onset of action (within 10-20 minutes), making it effective as a "rescue therapy" for sudden "off" episodes that occur despite optimized oral medication regimens.[1]
Apomorphine is unique among Parkinson's medications as the only approved injectable dopamine agonist that can be used either intermittently for rescue or continuously via infusion pump for patients with severe motor fluctuations. It was first approved by the FDA in 2004.
Apomorphine acts as a direct agonist at both D1-like (D1, D5) and D2-like (D2, D3, D4) dopamine receptors:[2]
Apomorphine has affinity for:
Apomorphine injection is indicated for acute rescue from "off" episodes:[3]
Dosing: Starting dose 0.2 mL (2 mg), titrated in 0.1 mL increments to optimal response. Maximum single dose 0.6 mL (6 mg). Typically 3-4 injections daily.
For patients with severe motor fluctuations, continuous subcutaneous infusion provides:[4]
Dosing: Continuous infusion 1-8 mg/hour (typically 3-4 mg/hour), titrated over 2-4 weeks.
Randomized controlled trials demonstrate:
| Parameter | Apomorphine Injection | Apomorphine Infusion |
|---|---|---|
| Onset | 10-20 min | Immediate (continuous) |
| Duration | 60-90 min | Variable |
| Use case | Rescue | Continuous control |
| Daily injections | 3-5 | 1 (catheter change daily) |
Ideal candidates for apomorphine therapy:
Research is exploring:[5]
The study of Apomorphine (Apokyn) has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
[1] Rascol O, et al. Subcutaneous apomorphine in Parkinson's disease. J Neural Transm (Vienna). 2019;126(4):371-379.
[2] Millan MJ, et al. Dopamine receptor agonists: from new structures to new clinical applications. Pharmacol Ther. 2019;198:1-45.
[3] Pahwa R, et al. Apomorphine in Parkinson disease: evidence-based review. Neurology. 2007;69(5):456-462.
[4] Katzenschlager R, et al. Apomorphine infusion in advanced Parkinson's disease: a systematic review. Parkinsonism Relat Disord. 2018;53:3-8.
[5] Olanow CW, et al. Apomorphine: past, present, and future. Mov Disord. 2022;37(9):1745-1758.