Tolerability of Rivastigmine Before and After Switching From Oral Formulation to Transdermal Patch in Alzheimer's Dementia

Inclusion Criteria: * With diagnosis of mild to moderate Alzheimer's disease. * Mini-Mental Status Examination score of 10-26 within 3 months before starting oral rivastigmine treatment. * A clinical diagnosis of probable AD according to NINCDS/ADRDA criteria. The brain scan (magnetic resonance imaging (MRI) or computed tomography (CT) used for establishing that these criteria are met must have been available on the source document within one year prior to study participation. * Patients who are currently taking or planned to receive Exelon 3 mg capsule twice-daily treatment. * Written informed consent must be obtained before any assessment is performed. * If female, must be surgically sterile or at least one year post-menopausal. * Sufficient education to read, write, and communicate effectively. * Capable of complying with the requirements of the study Exclusion Criteria: * Any advanced, severe or unstable disease that could interfere with study evaluation or completion or put patient at special risk. * Any medical or neurological condition other than AD that could explain the patient's dementia (e.g., abnormal thyroid function tests, Vitamin B12 or folate deficiency, posttraumatic conditions, Huntington's disease, Parkinson's disease, syphilis). * Active uncontrolled peptic ulceration, or gastrointestinal bleeding, within the previous 3 months prior to visit 1. * A current diagnosis of active, uncontrolled seizure disorder. * A history within the past year or current diagnosis of cerebrovascular disease (e.g., stroke, transient ischemic attacks, aneurysms). * Bradycardia (\< 50 beats per minute), sick sinus syndrome, conduction deficits (S-A block, second or third degree A-V block) * Severe or unstable cardiovascular disease. * Use of other investigational drugs at the time of enrollment, or within 30 days or 5 half-lives of enrollment, whichever is longer. * History of hypersensitivity to any of the study drugs or to drugs of similar chemical classes, or other components of the formulation. * Current diagnosis of a systemic active skin disorder or lesion that would prevent accurate assessment of the adhesion and skin irritation potential of the patch. * Previous lack of efficacy with cholinesterase inhibitors. * History of malignancy of any organ system (other than localized basal cell carcinoma of the skin), treated or untreated, within the past 5 years, regardless of whether there is evidence of local recurrence or metastases. Patients with history of malignancy yet have been treated and defined as complete remission for more than 5 years are not excluded from study participation. * Pregnant or nursing (lactating) women. * Concurrently treated with succinylcholine, similar neuromuscular blocking agents or cholinergic agonists such as bethanechol 2 weeks before the start of study drug and during the treatment period.