This chapter is a comprehensive account of Parkinson's disease and the
medicinal chemistry of antiparkinsonian drugs. It provides the mechanism of disease
progression and drug action and detail structure-activity relationships of the
antiparkinsonian drugs to give the knowledge base for pharmacists. After a study of
this chapter, students will be able to:
• Discuss the epidemiology and etiology of Parkinson disease (PD)
• Describe the clinical features of idiopathic PD and differentiate between cardinal
motor features and non-motor symptoms
• Discuss various risk factors and corresponding mechanisms responsible for the
development of PD symptoms
• Review biosynthesis of dopamine, its metabolic outcomes, dopaminergic pathways,
receptor distribution and corresponding signal transduction mechanisms
• Explain in detail the pathophysiologic mechanisms responsible for the clinical
features of idiopathic PD
• Evaluate the clinical role of L-DOPA and discuss its mechanism of action,
pharmacokinetics, adverse effects, motor complications, drug interactions,
contraindications and precautions
• For each medication class listed below, discuss their mechanism of action,
pharmacokinetics, adverse effects, motor complications, drug interactions,
contraindications and precautions
o Dopamine agonists
▪ ropinirole (Requip®, Requip® XL); pramipexole Mirapex®, Mirapex® ER);
rotigotine transdermal patch (Neupro®), and apomorphine (Apokyn®)
o Catechol-O-methyltransferase (COMT) inhibitors
▪ entacapone (Comtan®) and tolcapone (Tasmar®)
o Selective monoamine oxidase-B (MAO- B) inhibitors
▪ selegiline (Eldepryl® and Zelapar® ODT) and rasagiline (Azilect®)
▪ amantadine (Symmetrel®)
o Anticholinergic agents (benztropine (Cogentin®) and trihexyphenidyl)
Keywords: Parkinson’s disease (PD), Amantadine, Anticholinergic agents,
Antiparkinsonian drugs, Apomorphine, Benztropine, Catechol--
-methyltransferase (COMT) inhibitors, Dopamine (DA), Entacapone, L-DOPA
dopamine agonists, Muscarinic agents, Pramipexole, Rasagiline, Ropinirole,
Rotigotine, Selective monoamine oxidase-B (MAO-B) inhibitors, Tolcapone,
Selegiline, Structure-activity relationshipand drug-receptor.
