Definition
Rivastigmine is a reversible inhibitor of acetylcholinesterase and butyrylcholinesterase used primarily in the symptomatic treatment of mild to moderate dementia associated with Alzheimer's disease and Parkinson's disease.
Overview
Rivastigmine was approved for clinical use in the United States in 2000 and is marketed under the brand names Exelon, Exelon Patch, and others. It is administered orally in capsule or liquid form and transdermally as a skin patch, the latter providing a more constant plasma concentration and reducing gastrointestinal side effects. Clinical trials have demonstrated modest improvements in cognitive function, activities of daily living, and global clinical status compared with placebo. Common adverse effects include nausea, vomiting, loss of appetite, and weight loss; the transdermal formulation tends to have a lower incidence of these gastrointestinal events.
Etymology/Origin
The name “rivastigmine” is derived from its chemical structure and the naming conventions for cholinesterase inhibitors. The suffix “-stigmine” is commonly used for compounds that inhibit cholinesterase (e.g., physostigmine). The prefix “riva-” does not correspond to a specific linguistic root but serves to create a unique, trademark‑compatible identifier.
Characteristics
- Chemical classification: Carbamate derivative; IUPAC name: (S)-N‑ethyl‑3‑[1‑phenyl‑2‑(pyrrolidin‑1‑yl)ethyl]‑carbamate.
- Pharmacodynamics: Binds reversibly to the active site of acetylcholinesterase and butyrylcholinesterase, preventing the hydrolysis of acetylcholine and thereby enhancing cholinergic transmission in the central nervous system.
- Pharmacokinetics: Oral bioavailability is approximately 36 %; peak plasma concentrations occur 1–2 hours after dosing. The drug undergoes hepatic metabolism primarily via ester hydrolysis and is excreted mainly in urine. The transdermal patch delivers approximately 4.6 mg/24 h, achieving steady‑state concentrations within 3–4 days.
- Dosage forms: Capsules (1.5 mg, 3 mg, 4.5 mg), oral solution (1.5 mg/mL), and transdermal patches (4.6 mg/24 h, 9.5 mg/24 h).
- Regulatory status: Prescription‑only medication in most jurisdictions; listed on the World Health Organization’s Model List of Essential Medicines.
Related Topics
- Acetylcholinesterase inhibitors (e.g., donepezil, galantamine) – other therapeutic agents used for dementia.
- Alzheimer’s disease – neurodegenerative disorder for which rivastigmine is indicated.
- Parkinson’s disease dementia – another indication for rivastigmine therapy.
- Transdermal drug delivery – the technology employed for the rivastigmine patch formulation.
- Butyrylcholinesterase – an enzyme also inhibited by rivastigmine, contributing to its pharmacological profile.