The FDA approved the rivastigmine transdermal patch  (Exelon patch) for mild to moderate Alzheimer’s disease and Parkinson disease dementia.   Approval for the capsule form occurred in late June.  In clinical trials the patch was compared to bid dosing of the same medication in patients with moderate AD.  Study measurements included the Alzheimer’s disease Assessment Scale cognitive subscale and Alzheimer’s disease Cooperative Study-Clinical Global Impression of Change.

Rivastigmine is one of 3 approved cholinesterase inhibitors (prevents the breakdown of acetylcholine into acetate and choline, thereby increasing synaptic transmission).  Rivastigmine (Exelon), Adonepezil (Aricept) and galantamine (Reminyl, Razadine) have demonstrated modest, but not disease modifying effects in Alzheimer’s and other dementia patients.   The target does of the patch 9.5 mg/24 hrs. was as efficient as the highest oral does 12 mg/day.  One of the advantages of the patch is that it bypasses the GI tract, thereby avoiding some of the common side effects of oral preparations (nausea and vomiting).   The single daily dose also helps to encourage adherence.  There has been some skin reactions noted in patch users. These agents have a theoretically better chance of improving function in those patients with dementia and Lewy body pathology who have greater cholinesterase losses.  Providers need to reminder that these medications provide symptomatic relief but are not disease-modifying agents.