Dementia drugs: Understanding common side effects and how they may affect the heart

Drugs like cholinesterase inhibitors help manage some memory and thinking symptoms in dementia. Studies suggest that they can have some heart benefits, but some people can experience some side effects such as a slowing in heartbeat (bradycardia).

What do we mean by 'dementia drugs'?

Dementia is a complex term that covers different brain-related conditions, and it affects millions of people worldwide.

While there is no cure for the root causes of dementia, there are medications available to help manage its symptoms and improve the lives of those affected. 

Dementia drugs are specifically designed to relieve or control the symptoms of certain types of dementia, like Alzheimer's disease or dementia with Lewy bodies.

These drugs won't cure the condition, but they can make a significant difference in how people experience the challenges of dementia. 

What drugs are available to treat the cognitive symptoms of dementia?

One group of medications commonly used for treating cognitive symptoms in dementia is called 'cholinesterase inhibitors.'

These include donepezil, rivastigmine, and galantamine. There's also another drug known as memantine, which works differently to support symptom management. 

It's important to remember that these drugs may affect individuals differently. While these drugs may not work for everyone with dementia, they are still worth trying in most cases.

What are the common side effects of dementia drugs?

Like all medications, dementia drugs can have side effects. Some of the common side effects include:

  • vomiting
  • diarrhoea
  • loss of appetite
  • muscle pain
  • sleep problems
  • fatigue
  • headaches
  • itching or rash
  • dizziness
  • fainting
  • hallucinations
  • agitation
  • aggression

If you experience any of these symptoms while you are taking drugs for dementia, you should contact your GP as soon as possible.

Your GP may be able to offer an alternative treatment that is easier for you to take.

Dementia drugs and heart problems: what does the latest research say?

When it comes to heart health, recent research suggests that dementia drugs may have a positive impact on the heart and blood vessels.

People taking cholinesterase inhibitors, for instance, had a 37% lower risk of heart attacks or strokes and were less likely to die from heart-related issues.

However, it's essential to be aware of a rare condition called 'bradycardia,' where the heart beats too slowly. This can lead to dizziness and breathlessness, increasing the risk of falls, especially in older individuals. 

What is bradycardia?

One of the potential side effects of dementia drugs is bradycardia, a condition where the heart beats too slowly.

This can lead to inadequate blood flow to the brain, causing dizziness and breathlessness. For older individuals, this increases the risk of falls and serious injuries like hip fractures. 

To mitigate these risks, doctors may recommend the placement of a pacemaker for people with a very slow heartbeat. The pacemaker helps maintain a regular and faster heart rate, ensuring a sufficient blood supply to the brain. 

Before prescribing dementia drugs, your doctor is likely to conduct a thorough evaluation to check for any pre-existing heart problems. This precautionary step is essential to ensure that the medication is safe and appropriate for your specific health condition. 

The good news is that bradycardia is generally rare, and although dementia drugs may increase the risk of a slow heartbeat, the overall chances of developing this problem remain very low. 

On the other hand, heart attacks and strokes are relatively common in older individuals. Studies have shown that dementia drugs, such as donepezil, may help reduce the risk of these cardiovascular events, which is an encouraging benefit for those with dementia. 

If you are experiencing any side effects while taking dementia drugs, especially feelings of dizziness or fainting, it is crucial to discuss them with your GP promptly.

Your doctor can assess your heartbeat and evaluate the potential risks and benefits of continuing with the current medication.

Until advised otherwise by a healthcare professional, it is important to continue taking your medication as prescribed. 


This was first published in 2018 and most recently updated in August 2023.

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Hi my dad has dementia and is being put in hospice today. They want to take him off the dementia pills because she said after a while they start to hurt more than help. Is that true?

Hi Terri, 

First of all, we are sorry to hear about your dad's condition. It sounds like a difficult situation.

If ‘hurt’ means in this context that the side effects outweigh the benefits for memory and thinking, then it’s arguable that this might apply to some people – for example, if the pills are causing nausea, headaches or sleep disturbance.

Sometimes a decision is made to reduce the number of unnecessary medications that a person is taking if there is concern that they are taking so many that they’re interacting with each other or causing other difficulties.

It’s important to know that these are not life-extending medicines and their benefits even at the beginning are not massive. So it’s not critical that a person keeps taking them indefinitely.

However, if the medication doesn’t seem to be causing any noticeable side effects then it would be unusual to discontinue it based on a general policy of not encouraging its use in advanced dementia. This would go against evidence from clinical trials showing that people who come off this type of medicine in advanced dementia have slightly worse dementia symptoms than those who continued taking them – although the difference was still very small.

We hope this helps, Terri.

Alzheimer's Society Knowledge team

My mother was diagnosed with Alzheimer's..on airacept now and just added another pill starting with an m..memantadine .not sure or spell. She seems to be suddenly getting worse. Slower walking more anxious and more repetitive..are these side effects of the second drug
I began concern when I forgot a lot but wors,e some days the words don't come out right? I went to my doc and she put me on Donepezil. She looked at an MRI from a year ago and said my brain shunk. I am trying understand.. will it get worse. the drugs help but my brain will continue to shrink? What is the average life when Dementia has begun? I have talked with friends where the husband is on his second year but can't really talk. My brother died a year after his diagnosis. His wife is very evastive when I ask questions.

Hello. My Father has been on memantaine just under 12months I came back from a couple of days away and Mum tells me the Surgery have rung her to say that he has to stop taking them immediately . He has diabetes recent sepsis for the 4th time and prostate cancer and other problems . Why would they do this so suddenly. Thanks

Hi Dawn,

Thanks for getting in touch. Unfortunately we cannot comment on individual cases, but we would always suggest speaking with the surgery, as they are in the best position to answer any questions.

In the meantime, please call our Dementia Connect support line on 0333 150 3456 to talk to one of our trained dementia advisers for dementia information and support. More details (including opening hours) are available here:

We hope this helps, Dawn.

Alzheimer's Society blog team

Problem I having my husband can’t sleep night ,walk all night saying bad things about me I’m his wife for 60 years he talk bad to daughter and son-in-law leave go outside

Hi Gladys,

Thanks for getting in touch. I'm not sure from your comment whether your husband already has a diagnosis, but we'd recommend talking to your GP if he is displaying new symptoms.

If you'd like any support, please call our Dementia Connect support line on 0333 150 3456. You can talk to one of our trained dementia advisers so they can find out a bit more about your situation, and offer further information and advice. More details of the support line (including opening hours) are available here:

We hope this helps.

Alzheimer's Society blog team

my daughter 19 years old and art and design student. I found that she forget often, even she does not remember sometimes what she has eaten in breakfast, yesterday what he did on the whole day and where she traveled, etc. I am really worried I don't know whether she has careless behave that she does not pay attention to those things or something else.

Hi Tasneem,

Thanks for your comment, and sorry to hear about these concerns.

Dementia in somebody this young is very rare, but if you're worried about a sudden change in your daughter's behaviour then it's a good idea to talk to your GP about it.

If you'd like to talk this over with somebody first, you can also speak to one of our trained dementia advisers. Just call our Dementia Connect support line on 0333 150 3456:

Hope this helps, Tasneem.

Alzheimer's Society blog team

My brother is beginning to show symptoms, but he has a pacemaker, one of the main side effects is bradycardia. I am searching for a medication with no cardiac side effects or implications.

Hi Dorothea,

Thanks for getting in touch. I wasn't sure from your comment whether your brother already has a diagnosis, but it's a good idea to talk to your GP if he is displaying new symptoms, as well as starting any new drug treatments.

One of our dementia advisers can give you more support - please call our Dementia Connect support line on 0333 150 3456. You can talk to them so we can find out a bit more about your situation and provide information and advice. More details of the support line (including opening hours) are available here:

Hope this is helpful,

Alzheimer's Society blog team

My mother in law started having issues with basic daily things and memory, they did test & decided to try a memory pill( Donepezil) She was on it roughly about 2yrs and we noticed she was starting to get worse so we went back to dr and they said could take her off of this medicine, that it had done all it could do for her. Would there be a benefit for her to stay on this medication?

Hi Tricia,
We're sorry to hear about your mother-in-law's condition getting worse.
Unfortunately we cannot comment on individual cases. We would always suggest speaking with the doctor, as they are in the best position to answer any questions.
In the meantime, you may find this page from NHS on Donepezil informative:
Wishing you all the best, Tricia.
Alzheimer's Society blog team

My father has just started taking medication for dementia/Alzheimer's and has a very upset tummy. Can the body adjust and this side effect lessen with time?

Hi Janice, sorry to hear about your father. You should contact the doctor who prescribed this medication to ask about this issue.

Thank you

My husband is diagnosed with Parkinson Dementia. Since yesterday 5pm. He sleep, don t talk, refuse any tablet prescribed. It is 10am now. Cant make sense of all. What should I do?

Hello Nicole,
We're sorry to hear about your husband's condition. Unfortunately we cannot comment on individual cases, and would suggest that the doctor is in the best position to answer this.
We hope things improve soon, Nicole.
Alzheimer's Society blog team

Hi Joyce, I am so sorry to hear of your spouse’s condition. Mesothelioma is a horrible disease which is hard for anyone to go through, let alone a person with dementia who may struggle to understand their situation. Sadly it is all too common for someone with dementia to develop some form of cancer.

It sounds like your spouse is being well cared for. However, they do seem to be taking quite a lot of pills, particularly over-the-counter supplements. While there is unlikely to be any harm in this, it might be worth thinking about limiting their ‘pill burden’ if taking pills by mouth is becoming difficult – particularly the swallowing part. You can discuss this with your spouse’s doctor who should be able to advise further on the relative benefits of continuing with these.

Towards the end of life, it can sometimes be useful to review the prescription medications that a person is taking, so they only end up taking the ones that are providing real and immediate benefits. For a person with dementia, this can include reviewing the drugs they are taking to boost cognitive function.

Recent guidance from the National Institute for Health and Clinical Excellence (NICE) recommends that rivastigmine (Exelon) and memantine (Namenda) can be taken together in both the moderate and severe stages of Alzheimer’s disease (and also in some other types of dementia). NICE also recommends that these drugs should not be stopped just because a person is in the later stages of dementia (when it’s very difficult to know whether or not they’re working). This recommendation comes from a recent trial that compared quality of life in some people who were asked to stop taking these types of drugs versus others who were asked to keep taking them. The trial found that the people who stopped taking their anti-dementia medication had slightly worse symptoms than those who stayed on their medication. So, on average, it may be better to keep taking these drugs unless they are causing serious side effects or drug interactions. Again, this is something you can discuss in more detail with your spouse’s doctor.

In case you haven’t already come across these, you may find some of the information in these factsheets about end of life care useful. They cover many of the same issues, but from from their own particular perspectives:

End of life: a guide. A booklet for people in the final stages of life, and their carers’:…

Alzheimer’s Society factsheet: End of life care (contains useful information on physical needs, including eating and drinking and pain)…

British Lung Foundation: End of life with mesothelioma

You can also always call the Alzheimer’s Society helpline if you need to speak to someone about dementia-related problems, or the Macmillan Cancer Support helpline if you need more cancer-related advice:

Alzheimer’s Society National Dementia helpline: 0300 222 11 22
Monday to Wednesday 9am – 8pm
Thursday and Friday 9am – 5pm
Saturday and Sunday 10am – 4pm

Macmillan helpline: 0808 808 00 00
Monday to Friday, 9am – 8pm

I hope this helps.

Due to extreme stress, I must correct my previous email to you. My spouse takes the EXELON PATCH every day with NAMENDA. He was diagnosed in 2014 but has begun in 2011 with symptoms. I am questioning if these are helping to slow it down. I do believe they are. He also takes CBD pills, Turmeric, Mangosteen juice, Astragalus Tea pills, Algal 900 mg of DHA and vitamins, etc. Also dealing with Mesothelioma and blood clot in his left lung. He will be on hospice care in a matter of time as they cannot treat him anymore. He can be very witty when playing dominoes or a card game but doesn't remember if he ate his lunch which is kind of funny (I told him I can skip preparing a meal if I feel like it 'cause you don't know if you ate!) I would appreciate any advice or just an opinion of what's good or bad.

My spouse has been on Denepozil since 2013 and it is quite helpful -sorry about spelling-he does have some of the symptoms, dizziness, slow heart rate, sometimes nausea but in general, doing quite well. Would like to know info about Namenda which he takes at the same time. Also has Mesothelioma in rt lung, chemo caused blood clot in left lung has limited time and no more help for the cancer.