Erythromycin in Parkinson's Disease

Inclusion Criteria: * Subjects must have a definitive diagnosis of Parkinson's Disease (per United Kingdom brain bank criteria), Hoehn and Yahr stage 1-3, * must exhibit unequivocal levodopa responsiveness * must be able to distinguish between the "off" versus "on" state * Subjects must be on a stable dose of levodopa for at least 28 days prior to enrollment and should be anticipated to maintain a stable dose throughout both study periods * Subjects may be on concomitant therapy with Monoamine oxidase B inhibitors, entacapone, and amantadine, though the doses of these medications must have remained stable for at least 28 days prior to enrollment and must be expected to remain stable throughout both study periods. Exclusion Criteria: * History of deep brain stimulation for Parkinson Disease * History of ablative (tissue removal) surgery for Parkinson Disease * Presence of dementia (MMSE\<25) * Presence of active psychosis * History of any chronic gastrointestinal diseases * History of any prior gastrointestinal surgeries except for appendectomy, cholecystectomy, and hysterectomy * Any gastrointestinal surgeries in the past 3 months * Severe dysphagia (difficulty swallowing) to pills or food * History of physiological or mechanical gastrointestinal obstruction * History of strictures or fistulae (abnormal or narrow connections) along the gastrointestinal tract * History of gastric bezoars (undigested mass) * Allergy to wheat, soy, milk, or nuts * Presence of portable electromechanical devices such as pacemaker, defibrillator, or infusion pump * Female subjects who are pregnant or lactating * Symptomatic orthostatic hypotension (low blood pressure) * Diabetes * Presence of symptomatic anemia * Abnormal liver or kidney function * Cardiac arrhythmia (past or present) or abnormal QT interval on entrance EKG * Known hypersensitivity to any of the study drugs * Subjects receiving certain medications during specified time frames