Note: This is an overview of some of the common medications prescribed for treatment of Alzheimer’s disease.
For information on the anti-amyloid therapies approved by Health Canada in 2025, please view the Dementia Society’s webinar about this treatment available in Canada for early-stage Alzheimer’s disease; including how it works, eligibility, and important considerations around access and clinical decision-making.
Cholinesterase Inhibitors in the Early/Middle Stages
In the early or middle stages, a doctor may prescribe a Cholinesterase Inhibitor. This medication may improve
memory, help the person concentrate, and help with motivation. However, this medication cannot stop or slow
the progression of Alzheimer’s disease.
Some people also react better to one brand over another. Cholinesterase Inhibitors can go by the name of
Donepezil, Rivastigmine, or Galantamine. The brand-names are Aricept, Exelon, or Reminyl.
How do Cholinesterase Inhibitors Work?
Acetylcholine is a chemical in the brain that helps send messages from one brain cell to another. It is important for
memory, motivation, and concentration. A Cholinesterase Inhibitor stops Acetylcholine from breaking down.
When there is more Acetylcholine available, the brain cells can receive more messages.
Unfortunately, Alzheimer’s disease leads to a loss of brain cells over time. This medication cannot increase the
number brain cells available to use the Acetylcholine. This is why the medication might stop working as the
disease progresses.
Side Effects of Cholinesterase Inhibitors
Some people who take Cholinesterase Inhibitors report side effects. Side effects can include diarrhea, vomiting,
muscle cramps, or low blood pressure. Other side effects can be sleep problems, tiredness, and decreased hunger.
Some people report getting dizzy or falling. These side effects are more common when someone first takes the
medication.
NMDA Receptor Antagonists in the Late Stages
In the later stages, a doctor may prescribe an N-Methyl D-Aspartate (NMDA) Receptor Antagonist. This
medication may improve thinking, calms the person, and reduce delusions. It can allow the person to function
in their daily life for longer than they otherwise would. This medication goes by the name of Memantine and the
brand-name is Ebixa.
How do NMDA Receptor Antagonists work?
Glutamate is a chemical that the brain needs to work properly, but too much can be toxic. People with
Alzheimer’s disease have too much Glutamate in their brain. Glutamate attaches to specific areas on brain
cells called NMDA receptors. An NMDA-Receptor Antagonist blocks the area for a short amount of time.
This means that Glutamate cannot send messages into the cell.
This medication does not address the reason for all the extra Glutamate in the brain. This is why
medication will stop working at some point
Side Effects of NMDA Receptor Antagonists
Side effects are not very common. Some people might feel a little confused, dizzy, tired, have headaches or hallucinate.
How Well Do Alzheimer’s Medications Work for
Other Types of Dementia?
Vascular Dementia
These medications can have a small effect. The effect is better for a person who has both Alzheimer’s
disease and Vascular Dementia (Mixed Dementia). The medications can help with memory, motivation,
concentration, and thinking.
Frontotemporal Dementia
These medications are not effective for treating Frontotemporal Dementia. Some medications may even
make symptoms worse.
Dementia with Lewy Bodies
These medications may help improve thinking and attention.
Further Readings and Resources:
• iGeriCare, a free, online dementia education program developed by experts at McMaster University to support caregivers and families, offers an online lesson called “How is Dementia Treated?”
• This Dementia Society video features Bruyère Health physician Dr. Frank Knoefel presenting “The Science of Dementia”
• The Dementia Society offers many more fact sheets covering various dementia-related topics