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

Newspapers are often full of headlines about dementia. Recently some of them have written articles about whether or not dementia drugs might cause heart problems.

What do we mean by 'dementia drugs'?

Dementia is the broad term used to describe a number of different conditions affecting the brain.

There is currently no cure for the diseases that cause dementia.

However, some drugs can help to relieve or control symptoms for people living with Alzheimer’s disease, dementia with Lewy bodies or Parkinson’s disease dementia.

Unfortunately, there are currently no drugs that can improve the cognitive symptoms of vascular dementia or frontotemporal dementia.

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

The main drugs used to treat cognitive symptoms of dementia are called ‘cholinesterase inhibitors’.

Cholinesterase inhibitors include donepezil, rivastigmine and galantamine. There is also a drug called memantine, which works slightly differently.

These drugs don’t work for everyone, and the average effect is fairly small. But, for most people, they’re still well worth trying.

What are the common side effects of dementia drugs?

While many people can take dementia drugs without any problems, some may experience unpleasant side effects. The most common side effects include:

  • nausea, vomiting, diarrhoea
  • loss of appetite
  • muscle pain
  • sleep problems
  • feeling tired
  • headaches
  • itching or a rash
  • dizziness or feeling faint
  • hallucinations
  • agitation or 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?

The effect of dementia drugs on the health of a person’s heart and blood vessels appears to be generally quite positive.

A recent review of studies found that people who took cholinesterase inhibitors had a 37 per cent lower risk of having a heart attack or stroke.

The research study found that these people were also less likely to die from a heart-related problem.

However, the review also found an increased risk of a relatively rare problem called ‘bradycardia’.

What is bradycardia?

Bradycardia is when the heart beats too slowly. This can prevent enough blood from being pumped up to the brain, leaving the person feeling dizzy and breathless. This increases the risk of falling and sustaining a hip fracture, which is a really serious problem for older people in particular.

Because of the risks of falling, doctors often recommend that people with a very slow heart beat have a pacemaker fitted. This keeps the heart beating fast and regular enough to get a good supply of blood to the brain.

These issues are why your doctor is likely to check whether you have a pre-existing heart problem before prescribing these drugs.

So, the good news is that bradycardia is generally quite rare. Even though dementia drugs may increase the risk of having a slow heartbeat, the overall chances of developing this problem are still very low.

By contrast, heart attacks and strokes are quite common in older people, and dementia drugs like donepezil seem to reduce the risk of these happening.

It is very important to discuss any side effects you may be experiencing with your GP – particularly if these include feeling dizzy or faint. Your GP will be able to check your heart beat and assess the potential risks and benefits of continuing with your current medication. Keep taking your medication in the meantime, unless advised by a clinician to stop.

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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.

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