Dopamine Agonist Therapy in Parkinson's Disease Treatment

Parkinson’s disease (PD) is a neurodegenerative disorder characterised by progressive dopaminergic neuronal loss within the substantia nigra pars compacta. The resultant striatal dopamine deficiency underlies hallmark motor features such as bradykinesia, resting tremor and rigidity. Dopamine agonist therapy has become integral to PD management, either as monotherapy in early stages or in combination with levodopa to mitigate motor fluctuations and reduce dosage requirements. These agents directly stimulate post-synaptic dopamine receptors, offering prolonged receptor engagement and reduced risk of motor complications compared to levodopa alone. Continuous-delivery formulations, including transdermal patches and extended-release preparations, have refined pharmacokinetic profiles, smoothing dopaminergic stimulation and attenuating ‘on-off’ phenomena. Despite advances, challenges remain in balancing efficacy with neuropsychiatric and cardiovascular adverse effects. Emerging strategies now explore multi-modal regimens that combine receptor agonism with neuroprotective interventions to address both symptom control and underlying disease progression.

Research from Nature Portfolio

A comprehensive network meta-analysis across ten approved therapies compared motor outcomes and tolerability to inform optimal pharmacological choices. Levodopa, non-ergot dopamine agonists such as pramipexole and ropinirole, and the monoamine oxidase B inhibitor selegiline emerged with the highest overall benefit-to-risk profiles. The analysis highlighted that rotigotine and ropinirole demonstrated substantial improvements in motor scores with comparatively lower discontinuation rates, supporting their use in tailored treatment algorithms. This work provides a unified efficacy hierarchy, enabling clinicians to individualise therapy based on patient-specific risk and response characteristics.

Dopamine Agonist Therapy in Parkinson's Disease Treatment publication trend

The graph below shows the total number of articles in dopamine agonist therapy in parkinson's disease treatment across all publications each year (not limited to Nature Index journals).

Technical terms

Dopamine agonist: A pharmacological agent that binds to and activates dopamine receptors to mimic endogenous dopamine activity.

Levodopa equivalent dose (LED): A standardised metric that expresses the potency of different dopaminergic drugs relative to levodopa.

Network meta-analysis: A statistical method that enables simultaneous comparison of multiple interventions by integrating direct and indirect evidence.

Transdermal patch: A drug delivery system that administers medication through the skin for continuous systemic absorption.

Tyrosine hydroxylase: The rate-limiting enzyme in dopamine synthesis, converting tyrosine to L-DOPA.

D1 receptor: A subtype of dopamine receptor predominantly mediating excitatory signalling within the basal ganglia motor circuit.

References

1. Comparative efficacy and safety of adjunctive drugs to levodopa for fluctuating Parkinson’s disease - network meta-analysis. npj Parkinson's Disease (2023).
2. Tyrosine Hydroxylase Inhibitors and Dopamine Receptor Agonists Combination Therapy for Parkinson’s Disease. International Journal of Molecular Sciences (2024).
3. Dopamine D1 Agonists: First Potential Treatment for Late-Stage Parkinson’s Disease. Biomolecules (2023).