Which combination of drug classes is commonly used in the pharmacologic treatment of Alzheimer's disease?

• A. NMDA receptor antagonists alone
• B. Acetylcholinesterase inhibitors alone
• C. Acetylcholinesterase inhibitors plus NMDA receptor antagonist Memantine
• D. Dopamine agonists and MAO inhibitors

Answer: (C)

Alzheimer's treatment aims to address two different problems in the brain: reduced cholinergic signaling and harmful glutamate activity. Acetylcholinesterase inhibitors boost acetylcholine levels, which can improve memory and function in mild to moderate disease. Memantine, an NMDA receptor antagonist, helps prevent excitotoxic damage from glutamate and is particularly helpful as the disease progresses to moderate or severe stages. Using them together provides additive benefit because they target separate disease mechanisms, so the combination of an acetylcholinesterase inhibitor with memantine is commonly used. Dopamine-related drugs aren’t typically used for Alzheimer's, and memantine alone is less common in earlier stages, reinforcing why the combination is the preferred approach.