Medication for Dementia - Donepezil
Let’s deep dive into the most commonly prescribed medication for dementia, specifically Alzheimer’s disease, donepezil. Donepezil is an acetylcholinesterase inhibitor, meaning it works in the brain to prevent the breakdown of the neurotransmitter acetylcholine. To keep it simple, imagine a person whispering to another person (a nerve talking to another nerve) and acetylcholine is the word or message in that whisper. Donepezil does its job by preventing that message from being erased too soon so that the person (nerve) receiving the message has a chance to hear it!
Originally developed in 1983 and entering the market in 1996, donepezil is the most widely available medication for dementia related to Alzheimer’s disease despite only having a tiny effect on the progression of the disease. Donepezil comes in three doses, 5 - 10 - 23. 5mg is typically the starting dose with escalation to 10mg if there are no adverse side effects. Common side effects are nausea and diarrhea as acetylcholine is also a neurotransmitter involved in the “rest and digest” phase of the body’s cycle. Up to 1 in 3 people will experience these side effects and may need to stop taking the medication because of them. Another less common, but more frightening, side effect is that donepezil can also slow the heart rate to the point that a person must limit their physical activity. This is called symptomatic bradycardia and if this occurs the medication must be stopped. The 23mg dosage does not have any benefits over the standard treatment dose of 10mg but the side effects occur much more frequently.
Donepezil has been extensively studied over the past twenty years, and the most recent Cochrane review shows that after six months of treatment people with dementia who are taking the medication score about 2.5 points better on a 70 point scale and may be able to handle day to day activities like getting dressed better than people with dementia who are not taking the medication. Donepezil has not, at this point, been vigorously studied past six months but many people remain on it for years. It does not prevent the need to move to a nursing home or quality of life.
Ultimately Alzheimer’s disease is a fatal and progressive disease and donepezil has not proven to alter the course of the disease. It is important to keep an open line of communication with those that are important in your life to know their wishes and to do What Matters! With the ever increasing aging population, the frequency of Alzheimer’s disease is increasing which highlights the importance of doing our best to age in a healthy manner and to do the things that Matter before it is too late!
Key Points:
Donepezil increases the neurotransmitter acetylcholine in the brain
People with Alzheimer’s disease on donepezil score better on dementia tests and may handle day to day tasks better, but there is only evidence for 6 months of treatment
Alzheimer’s disease is a progressive and fatal disease; donepezil does not alter the disease progression
