OBJECTIVE: To evaluate the role of the practicing pharmacist in the 
identification and current treatment of the levodopa wearing-off phenomenon 
experienced by patients with Parkinson's disease (PD) who are receiving chronic 
levodopa therapy.
DATA SOURCES: Literature retrieval was accessed through MEDLINE (1967-June 2007) 
using the terms levodopa, wearing-off, and Parkinson's disease. In addition, 
reference citations from publications identified were reviewed.
STUDY SELECTION AND DATA EXTRACTION: All articles that were identified from the 
data sources and written in English were evaluated.
DATA SYNTHESIS: Levodopa is the most efficacious therapeutic agent in PD; 
however, the response of patients to levodopa changes over time. Eventually, the 
duration of response becomes shorter and more unpredictable, and complications 
emerge. One of the first complications observed with levodopa therapy is 
wearing-off, which can emerge within 1-3 years of initiation of levodopa 
treatment. Wearing-off is characterized by the predictable emergence of motor 
and nonmotor PD symptoms before the next scheduled dose of medication. Despite 
effective treatment options to tackle wearing-off, it remains underrecognized 
and under treated. With early identification and optimization of treatment, 
wearing-off can be managed effectively, resulting in improved quality of life 
for patients with PD.
CONCLUSIONS: Owing to their training and accessibility, pharmacists play an 
increasingly important role in the management of patients with PD. Pharmacists 
are uniquely placed to identify wearing-off, offer timely advice, and facilitate 
the optimization of treatment regimens to improve patients' quality of life and 
enhance long-term outcomes.