OBJECTIVE: Assess the cost-effectiveness of rasagiline, a potent, selective, and irreversible monoamine oxidase-B inhibitor and second-generation dopamine agonists ropinirole and pramipexole (DAs) for delaying levodopa-related motor complications (delaying levodopa start) in patients with early Parkinson's disease (PD) in the UK. Development of motor complications is related to duration under levodopa, and clinical consensus in PD management advises postponing levodopa treatment. METHODS: We compared cost-effectiveness in starting treatment with rasagiline versus second-generation DAs in early PD patients. A 5-year probabilistic Markov model with 3 states: ‘under rasagiline', ‘under DA' and ‘levodopa start' was used. Model inputs included transition probabilities from randomised clinical trials in early PD for rasagiline and DAs, and costs and resources from an English cost-of-illness study. Effectiveness measure was number of years before levodopa request. Primary analysis was performed from the NHS perspective. Sensitivity analysis was performed varying ropinirole dose. Prices for rasagiline, pramipexole and ropinirole were obtained from the NHS based on WHO-DDD. RESULTS: Over five years, time without levodopa was greater when early PD patients' treatment was initiated with rasagiline compared with DAs (3.93 vs. 2.65 years). There was a small increase in costs of £1807 compared with DAs. Incremental cost effectiveness was £1411.7 per patient per year before levodopa compared with DAs. Cost-effectiveness acceptability curve shows that with a willingness to pay of £1704 per year without levodopa, rasagiline has a 95% probability of being cost-effective. Sensitivity analysis on ropinirole dose confirmed that rasagiline was cost-saving for a differential gain of 1.28 years and dominates ropinirole. CONCLUSIONS: This economic model demonstrates initiating treatment with rasagiline is a cost-effective alternative compared with initiating DAs in delaying time to levodopa. Further studies are necessary to evaluate if delaying motor complications in advanced PD will offset the slight increases in costs observed.