A method of treating the symptoms of Parkinsons disease comprises implanting a reservoir-based drug delivery composition into a subject to systemically deliver a therapeutically effective amount of rasagiline to the subject for a long period of time (e.g., one month or one year). The drug delivery composition may include a rate-controlling excipient (e.g., an elastomeric polymer) defining a reservoir containing at least one discrete solid dosage form (e.g., one or more pellets), which includes rasagiline hemitartrate and optionally, a sorption enhancer.
