My mum has just been diagnosed with Alzheimers and has been put on Memantine as it was thought Donepizil may upset her stomach. Since the first week on 5mg she has experienced diarrhea progressively getting worse as we went up to 10mg. The advice from the memory clinic was to take it back to 5mg for a week to see if it settles. It hasn't .She takes the tablet at bedtime so the diarrhea is worse in the morning but bouts of it can last through to the afternoon (like today!) She is now starting week 4 and is still on 5mg . Did anyone else's relatives experience this side effect? and if it did settle how long did it take? Her quality of life is suffering but Mum is keen to keep taking it. TIA
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Memantine-side effects
- Thread starter Anna328
- Start date
Hello @Anna328 and welcome, you'll find lots of friendly support and advice here. I don't have personal experience of memantine (mum was on donepezil) but I know that other members here do so I'm sure someone will be along soon. Did the memory clinic suggest anything for the diarrhea? If not then it may be worth speaking to your mum's GP to see what they advise as frequent diarrhea, aside from not being pleasant for your mum, can lead to dehydration. It may be that a change of dementia medication is required if it continues. Was there a reason for the memory clinic thinking that donepezil may upset your mum's stomach - does she have other health problems that might be causing the diarrhea?
Hi, my mum was put on this, she has mixed dementia, she didn’t tolerate it very well at all and like you they altered the dosage but it had a terrible effect on her and she lost significant weight. Mum is also Type 2 diabetic so in the end we insisted she stopped taking it. I don’t see the point in creating other health problems to reduce the effects of her dementia, which to be honest was more manageable than the constant diarrhoea! Hope you can resolve this for your mum.My mum has just been diagnosed with Alzheimers and has been put on Memantine as it was thought Donepizil may upset her stomach. Since the first week on 5mg she has experienced diarrhea progressively getting worse as we went up to 10mg. The advice from the memory clinic was to take it back to 5mg for a week to see if it settles. It hasn't .She takes the tablet at bedtime so the diarrhea is worse in the morning but bouts of it can last through to the afternoon (like today!) She is now starting week 4 and is still on 5mg . Did anyone else's relatives experience this side effect? and if it did settle how long did it take? Her quality of life is suffering but Mum is keen to keep taking it. TIA
Thank you. I feel the same way. She is slight and cant afford to loose weight.i am worried about this. I would prefer she has a good quality of life where she can leave her flat and the toilet.Hi, my mum was put on this, she has mixed dementia, she didn’t tolerate it very well at all and like you they altered the dosage but it had a terrible effect on her and she lost significant weight. Mum is also Type 2 diabetic so in the end we insisted she stopped taking it. I don’t see the point in creating other health problems to reduce the effects of her dementia, which to be honest was more manageable than the constant diarrhoea! Hope you can resolve this for your mum.
It really is . We had such hopes for the medication. Glad your Mum was ok.Mums been taking it for 18 months and no diarrhoea; it must be very draining for your poor mum
Hi Louise,Hello @Anna328 and welcome, you'll find lots of friendly support and advice here. I don't have personal experience of memantine (mum was on donepezil) but I know that other members here do so I'm sure someone will be along soon. Did the memory clinic suggest anything for the diarrhea? If not then it may be worth speaking to your mum's GP to see what they advise as frequent diarrhea, aside from not being pleasant for your mum, can lead to dehydration. It may be that a change of dementia medication is required if it continues. Was there a reason for the memory clinic thinking that donepezil may upset your mum's stomach - does she have other health problems that might be causing the diarrhea?
Mum is very slight and is quite sensitive to drugs .No other problems that would lead to this .She's been taking all her other meds with no problem. GP has taken a stool sample just in case. The thinking was that donepezil would potentially upset her stomach. One of the highlighted side effects on Google. Although i will be asking the memory clinic about alternatives. The GP had given her tablets to take after a loose movement but today i discovered she hadn't been taking them! Poor Mum was feeling so weak. She is normally so good at taking her meds but i think she just didn't know what they were for.
Hello @Anna328.
My wife has been taking both Memantine and Donepezil for a few years now and hasn't suffered this side effect.
A few months after starting Memantine it was stopped as it was thought that a side effect was creating a nasty symptom, but it wasn't diarrhoea. At the time I protested that my wife's symptom wasn't noted as a side effect of Memantine but I was told that it was too much of a coincidence and the med was stopped The nasty symptom continued so it wasn't a side effect and the med was reinstated. When my wife went on Memantine it improved her and she deteriorated quickly when it was stopped. After the med was reinstated my wife improved again. Diarrhoea is not noted as a side effect of Memantine so I would watch carefully when, and if, it's stopped in case something else is at play and may need treatment.
Donepezil was prescribed to be taken each morning by my wife but it upset her stomach so we switched to taking it at bedtime and that solved that issue.
My wife has been taking both Memantine and Donepezil for a few years now and hasn't suffered this side effect.
A few months after starting Memantine it was stopped as it was thought that a side effect was creating a nasty symptom, but it wasn't diarrhoea. At the time I protested that my wife's symptom wasn't noted as a side effect of Memantine but I was told that it was too much of a coincidence and the med was stopped The nasty symptom continued so it wasn't a side effect and the med was reinstated. When my wife went on Memantine it improved her and she deteriorated quickly when it was stopped. After the med was reinstated my wife improved again. Diarrhoea is not noted as a side effect of Memantine so I would watch carefully when, and if, it's stopped in case something else is at play and may need treatment.
Donepezil was prescribed to be taken each morning by my wife but it upset her stomach so we switched to taking it at bedtime and that solved that issue.
Hi Anna328My mum has just been diagnosed with Alzheimers and has been put on Memantine as it was thought Donepizil may upset her stomach. Since the first week on 5mg she has experienced diarrhea progressively getting worse as we went up to 10mg. The advice from the memory clinic was to take it back to 5mg for a week to see if it settles. It hasn't .She takes the tablet at bedtime so the diarrhea is worse in the morning but bouts of it can last through to the afternoon (like today!) She is now starting week 4 and is still on 5mg . Did anyone else's relatives experience this side effect? and if it did settle how long did it take? Her quality of life is suffering but Mum is keen to keep taking it. TIA
unfortunately diarrhoea & constipation are listed as some of the many side effects of Memantine,
I guess the digestive system takes time to adjust to this medicine.
My mum had many side effects that lasted many many weeks, stick with it if doctors advise it.
But keep consulting doctors, if you can't get through to doctor, the pharmacy give advice.
ALWAYS CHECK WITH MEDICAL PEOPLE!
Drink fluids
Diarrhoea can lead to dehydration, so you should drink plenty of fluids – small, frequent sips of water
It's important to drink plenty of fluids to avoid dehydration, particularly if you're also vomiting.
Take small, frequent sips of water.
Ideally, adults should drink a lot of liquids that contain water, salt, and sugar. Examples are water mixed with juice and soup broth. If you're drinking enough fluid, your urine will be light yellow or almost clear.
Some foods to avoid while experiencing diarrhoea include (though check with doctors 1st)
Drink fluids
Diarrhoea can lead to dehydration, so you should drink plenty of fluids – small, frequent sips of water
It's important to drink plenty of fluids to avoid dehydration, particularly if you're also vomiting.
Take small, frequent sips of water.
Ideally, adults should drink a lot of liquids that contain water, salt, and sugar. Examples are water mixed with juice and soup broth. If you're drinking enough fluid, your urine will be light yellow or almost clear.
Some foods to avoid while experiencing diarrhoea include (though check with doctors 1st)
- milk and dairy products (including milk-based protein drinks)
- fried, fatty, greasy foods
- spicy foods
- processed foods, especially those with additive foods
- alcohol
- coffee, soda, and other caffeinated or carbonated drinks
- artificial sweeteners
I googled "memantine side effects" & Diarrhoea is listed on most of the results.Hello @Anna328.
My wife has been taking both Memantine and Donepezil for a few years now and hasn't suffered this side effect.
A few months after starting Memantine it was stopped as it was thought that a side effect was creating a nasty symptom, but it wasn't diarrhoea. At the time I protested that my wife's symptom wasn't noted as a side effect of Memantine but I was told that it was too much of a coincidence and the med was stopped The nasty symptom continued so it wasn't a side effect and the med was reinstated. When my wife went on Memantine it improved her and she deteriorated quickly when it was stopped. After the med was reinstated my wife improved again. Diarrhoea is not noted as a side effect of Memantine so I would watch carefully when, and if, it's stopped in case something else is at play and may need treatment.
Donepezil was prescribed to be taken each morning by my wife but it upset her stomach so we switched to taking it at bedtime and that solved that issue.
That's interesting, I go by the leaflet that's contained in the pill box and it's not listed there.I googled "memantine side effects" & Diarrhoea is listed on most of the results.
I suppose the Google results may be based on anecdotal evidence that wasn't seen in clinical trials. Maybe the manufacturers should update their package leaflet.
In any case, my comment that a watch should be kept if the med is stopped still stands.
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Thank you Pete, the diarrhoea coincided with Mum starting the Memantine but we have done a stool sample just in case.Hello @Anna328.
My wife has been taking both Memantine and Donepezil for a few years now and hasn't suffered this side effect.
A few months after starting Memantine it was stopped as it was thought that a side effect was creating a nasty symptom, but it wasn't diarrhoea. At the time I protested that my wife's symptom wasn't noted as a side effect of Memantine but I was told that it was too much of a coincidence and the med was stopped The nasty symptom continued so it wasn't a side effect and the med was reinstated. When my wife went on Memantine it improved her and she deteriorated quickly when it was stopped. After the med was reinstated my wife improved again. Diarrhoea is not noted as a side effect of Memantine so I would watch carefully when, and if, it's stopped in case something else is at play and may need treatment.
Donepezil was prescribed to be taken each morning by my wife but it upset her stomach so we switched to taking it at bedtime and that solved that issue.
Thank you for all the advice. Hoping to speak to her Dr at the memory clinic today to advise. There does seem to be a period of adjustment for some people but it’s just difficult when you see your loved one suffering from the effects and you wonder how long the settling in will take. She is on other medication and one of my worries is that these medicines will be flushed out of her system before they can be absorbed and work. It’s a balancing act. It’s great to hear other people’s experiences to inform me and help when having to speak to Drs.
Hi k-Pete, I noticed that the USA list the drug as having that side effect, while a lot of UK sources don't.That's interesting, I go by the leaflet that's contained in the pill box and it's not listed there.
I suppose the Google results may be based on anecdotal evidence that wasn't seen in clinical trials. Maybe the manufacturers should update their package leaflet.
In any case, my comment that a watch should be kept if the med is stopped still stands.
Hi @CJG20.Hi k-Pete, I noticed that the USA list the drug as having that side effect, while a lot of UK sources don't.
That's a bit disturbing as one would think there should be an international standard for such things. My wife is on that med and I'd hate to think I might miss a side effect because it's not listed on our leaflets here.
Mind you, any side effect would have to be serious before I'd agree to the med being stopped as the short break my wife had produced a dramatic worsening of her dementia.
Aren't there always complications with dementia(sigh)!
Hi k-Pete,Hi @CJG20.
That's a bit disturbing as one would think there should be an international standard for such things. My wife is on that med and I'd hate to think I might miss a side effect because it's not listed on our leaflets here.
Mind you, any side effect would have to be serious before I'd agree to the med being stopped as the short break my wife had produced a dramatic worsening of her dementia.
Aren't there always complications with dementia(sigh)!
my browser history has been mostly USA politics because of Trump & the election etc, therefore most of my search results for "Memantine side effects" returned USA results,
I then researched "Memantine side effects UK" and got different result as UK didn't list Diarrhoea.
IMHO I believe its down to an individual countries code of practice & what is or isn't a side effect,
the USA would from what I've read, deem Diarrhoea a side effect, while UK would not.
This is obviously just an assumption at this stage & will need further research.
Kind Regards
CJG20
I found this if anyone feels they need to highlight a side effect
Patients and health professionals reporting suspected adverse drug reactions to the Yellow Card Scheme help contribute to these important processes. Suspected reactions can be reported online at www.mhra.gov.uk/yellowcard
Patients and health professionals reporting suspected adverse drug reactions to the Yellow Card Scheme help contribute to these important processes. Suspected reactions can be reported online at www.mhra.gov.uk/yellowcard
My wife takes Memantine but has constipation problems sometimes missing 2 daysMy mum has just been diagnosed with Alzheimers and has been put on Memantine as it was thought Donepizil may upset her stomach. Since the first week on 5mg she has experienced diarrhea progressively getting worse as we went up to 10mg. The advice from the memory clinic was to take it back to 5mg for a week to see if it settles. It hasn't .She takes the tablet at bedtime so the diarrhea is worse in the morning but bouts of it can last through to the afternoon (like today!) She is now starting week 4 and is still on 5mg . Did anyone else's relatives experience this side effect? and if it did settle how long did it take? Her quality of life is suffering but Mum is keen to keep taking it. TIA
