You are preparing to administer cholinesterase inhibitor to a patient with Alzheimer's disease. Which medication, if ordered by the provider, should you question?

A. Famotidine (Pepcid) is an H2-receptor antagonist used to reduce gastric acid. It does not significantly interact with cholinesterase inhibitors and is generally safe to administer concurrently. B. Levothyroxine (Synthroid) is a thyroid hormone replacement. It does not interfere with cholinesterase inhibitors, and there are no major contraindications for concurrent use. C. Memantine (Namenda) is an NMDA receptor antagonist used in moderate to severe Alzheimer’s disease. It is often used in combination with cholinesterase inhibitors to improve cognition and function, and the combination is considered safe and appropriate. D. Amitriptyline (Elavil) is a tricyclic antidepressant with anticholinergic properties. Cholinesterase inhibitors increase acetylcholine activity, while amitriptyline blocks acetylcholine receptors, which can counteract the therapeutic effects of the cholinesterase inhibitor. Concurrent use may reduce efficacy and worsen cognitive function in Alzheimer’s patients.