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Ongoing Metformin Side Affects

pau1200

Well-Known Member
Hi,

When I was out on metformin my stomach could cope as I suffered regular diarrhoea. I was switched to slow release and that for the most part is ok but still suffer with occasional bouts of diarrhoea. It’s always the same aggressive type just after eating and is similar to when I was on normal metformin. My doctor doesn’t think it’s the metformin as after 2 years my body should have adapted and he thinks it’s my diet, which is low carb currently. This diarrhoea problem has been there since I started metformin but is less regular on the slow release.

I want my doctor to do more but he seems to think it’s normal and I should change diet. Just wondering if anyone else has suffered ongoing diarrhoea bouts after eating related to metformin.
 
So you have suffered with diarrhea for 2 years and your Dr is blaming a low carb diet not Metformin which is well known for causing gastric problems. If I had your Dr I wouldn't want him to do more, I would do my best to stay away from him.
If I were in your position I think I would have a break from Metformin for a few weeks. If the stomach trouble cleared up the pills would go in the bin. If not I would ask to see another Dr
 
He believes that any side affects are short lived and it’s my diet that causes these bouts of diarrhoea. I’m trying to find out if people still continue to suffer with occasional diarrhoea even on the slow release. It’s not bad enough to affect my day to day life and sometimes it can go months between suffering, other time weeks. Trying to get anything out of my doctor is a pain. He was happy with my last review but speaking to him on the phone about this has said he wants my bloods again and there was traces of protein in my urine but didn’t mention anything at the review.

I
 
He believes that any side affects are short lived and it’s my diet that causes these bouts of diarrhoea. I’m trying to find out if people still continue to suffer with occasional diarrhoea even on the slow release. It’s not bad enough to affect my day to day life and sometimes it can go months between suffering, other time weeks. Trying to get anything out of my doctor is a pain. He was happy with my last review but speaking to him on the phone about this has said he wants my bloods again and there was traces of protein in my urine but didn’t mention anything at the review.

I

Just anecdotal, but I find the low carb diet for me has a tendency to make me constipated, despite being on Metformin. I have to ensure I eat plenty of nuts and seeds to ‘keep things regular’!
 
10 years on Metformin, on slow release but I still suffer bouts of urgent diarrhoea. It is worse with low carb diet, but blood sugar is better so I’m not changing that.

things have been much more difficult since COVID as more public toilets have been unavailable.
 
Hi,

When I was out on metformin my stomach could cope as I suffered regular diarrhoea. I was switched to slow release and that for the most part is ok but still suffer with occasional bouts of diarrhoea. It’s always the same aggressive type just after eating and is similar to when I was on normal metformin. My doctor doesn’t think it’s the metformin as after 2 years my body should have adapted and he thinks it’s my diet, which is low carb currently. This diarrhoea problem has been there since I started metformin but is less regular on the slow release.

I want my doctor to do more but he seems to think it’s normal and I should change diet. Just wondering if anyone else has suffered ongoing diarrhoea bouts after eating related to metformin.

Thank you for posting this. I am also on slow release Metformin. I’ve just started eating out again as was shielding and have met friends for lunch last 2 days. I’ve hardly finished the main course when I’ve had to rush to toilet . Only was to beat it was to take 2 Imodium. I never thought about the Metformin although in past I’ve not been able to “stomach” taking more than 1 Metformin at a time. I’m not really on low carb so can’t blame that.

(Mod edit for clarity - sorting out quote/comments)
 
Last edited by a moderator:
My doctor doesn’t think it’s the metformin as after 2 years my body should have adapted and he thinks it’s my diet, which is low carb currently.

Your doctor I'm afraid is a moron.. why not try without metformin for a week and see if the diarrhoea goes away?
 
Your doctor I'm afraid is a moron.. why not try without metformin for a week and see if the diarrhoea goes away?

The problem is it can be really intermittent I could go weeks between suffering again. If I am out with work I tend not to take my metformin on the morning just in case. This is not ideal but works for me.

I may have to do some testing with and without and see what happens, it’s nice to know I’m not alone though
 
I gave up the tablets just before Christmas 2016 as it was just too dreadful to live with the effects - two days later and I was making plans for visiting family at Christmas, travelling two hours each way to visit our son and family, out all day on Christmas day.
Since then I have had no problem at all despite eating a low carb diet every day.
My numbers are normal for blood glucose and at the top end of normal for Hba1c, but I think that is just how I am.
How a low carb diet could cause diarrhoea rather baffles me - it is more commonly associated with the reverse effect, as it is low residue so there isn't as much to get rid of.
Maybe eating something really fatty might affect some people, but my money would be on the Metformin, and I don't bet.
I do wonder, though, what your doctor wants you to change your diet to - and if he thinks it would be effective in controlling your blood glucose levels.
 
The problem is it can be really intermittent I could go weeks between suffering again. If I am out with work I tend not to take my metformin on the morning just in case. This is not ideal but works for me.

I may have to do some testing with and without and see what happens, it’s nice to know I’m not alone though
Hi I had exactly the same issue, after a year I came off it for a fortnight and my BG figures improved, my nurse then agreed that the days I had diarrhoea were probably aggravating my stomach so much it was raising my BG. I would usually have a day a week where I had trouble even leaving the house, I am type 1 LADA so also on insulin so I wouldn’t advise not taking anything if you are just on metformin talk to them about an alternative. I also have a friend who has been type 2 for about 20 years and she intermittently is sick with a ‘metformin day’ as she calls it. Until I took it I never fully understood, she has exactly the same problem.
 
I gave up the tablets just before Christmas 2016 as it was just too dreadful to live with the effects - two days later and I was making plans for visiting family at Christmas, travelling two hours each way to visit our son and family, out all day on Christmas day.
Since then I have had no problem at all despite eating a low carb diet every day.
My numbers are normal for blood glucose and at the top end of normal for Hba1c, but I think that is just how I am.
How a low carb diet could cause diarrhoea rather baffles me - it is more commonly associated with the reverse effect, as it is low residue so there isn't as much to get rid of.
Maybe eating something really fatty might affect some people, but my money would be on the Metformin, and I don't bet.
I do wonder, though, what your doctor wants you to change your diet to - and if he thinks it would be effective in controlling your blood glucose levels.

My old doctor was brilliant, this new one I’m not impressed with, maybe I’m just being a bit harsh on him with the pandemic.
He gave me no indication of what my diet should be, he did ask about passing blood etc but if I’m honest he was a bit rude about me weight. I am overweight but since being T2 I’ve lost about 3 stone. I’m still really overweight and working it but I think he thought 2+ years and I should be back to normal.

I am not going to change my diet and it does sound and feel like the metformin. My levels are ok but probably not good enough yet to come if metformin but I think that’s what I will work towards.
 
My old doctor was brilliant, this new one I’m not impressed with, maybe I’m just being a bit harsh on him with the pandemic.
He gave me no indication of what my diet should be, he did ask about passing blood etc but if I’m honest he was a bit rude about me weight. I am overweight but since being T2 I’ve lost about 3 stone. I’m still really overweight and working it but I think he thought 2+ years and I should be back to normal.
I am not going to change my diet and it does sound and feel like the metformin. My levels are ok but probably not good enough yet to come if metformin but I think that’s what I will work towards.
If ever I find I am thinking about eating something I shouldn't I just ask myself if I want to be pushed into taking Metformin again - my resolve suddenly recovers it good sense and I don't eat it.
My weight is probably going to be normal eventually, but I have had so much grief over the years from HCPs with really bad advice, I am just not going to weigh myself.
 
The problem is it can be really intermittent I could go weeks between suffering again.

Do you get any other gastric effects aside from diarrhoea? If it is as intermittent as every few weeks, I’m wondering whether it is food related? Not a low carb diet problem per se, but a reaction to certain foods/drinks? Perhaps noting down what you eat for a while would help to eliminate that possibility?

For my own part, I’ve never taken metformin, so can’t comment but find that any bowel issues - either constipation or diarrhoea can usually be tracked to what I have/haven’t consumed. The former is easily resolved by drinking more water, with a bit of salt added. The latter can usually be attributed to over consumption of things like cream/very high cocoa percentage chocolate.

It’s all trial and error and I hope you find a solution.
 
Hi,

When I was out on metformin my stomach could cope as I suffered regular diarrhoea. I was switched to slow release and that for the most part is ok but still suffer with occasional bouts of diarrhoea. It’s always the same aggressive type just after eating and is similar to when I was on normal metformin. My doctor doesn’t think it’s the metformin as after 2 years my body should have adapted and he thinks it’s my diet, which is low carb currently. This diarrhoea problem has been there since I started metformin but is less regular on the slow release.

I want my doctor to do more but he seems to think it’s normal and I should change diet. Just wondering if anyone else has suffered ongoing diarrhoea bouts after eating related to metformin.
Hi I was on Metformin for 3 year I was constantly on the toilet with violent tummy upset ..I spoke with my Dr and he took me off and put me on trulisity injection once a week I've had no problems since and my toilet trouble is over
 
Do you get any other gastric effects aside from diarrhoea? If it is as intermittent as every few weeks, I’m wondering whether it is food related? Not a low carb diet problem per se, but a reaction to certain foods/drinks? Perhaps noting down what you eat for a while would help to eliminate that possibility?

For my own part, I’ve never taken metformin, so can’t comment but find that any bowel issues - either constipation or diarrhoea can usually be tracked to what I have/haven’t consumed. The former is easily resolved by drinking more water, with a bit of salt added. The latter can usually be attributed to over consumption of things like cream/very high cocoa percentage chocolate.

It’s all trial and error and I hope you find a solution.
I was on metformin for a long time. I found occasional issues tended to tie into things I ate. Things like lasagne, or bolognaise actually, the meat and tomato combinations seemed to not really settle well with me. I also found sometimes when I ate chips in restaurants I would get bad cramps. I narrowed it down to something to do with too much oil in the frying

The intermittent nature could be metformin of course, but its worth looking into I think
 
Thanks everyone for the suggestions, it may be food and merformin related. I am keeping a good diary again to see if I can spot any sort of pattern or relationship to food.
 
FWIW - when I changed surgeries a few years ago my brand got changed to Morningside's Sukkarto - it didn't dissolve consistently so I used to get these bouts of diarrhea as you described - if you read the pamphlet one of the added ingredients is shellac. My HBA1c rose consistently from that point with no changes to my LC diet until the one at Christmas alarmed my DN enough to put me on Forxiga too. However she did listen to me about the Sukkarto and since getting my doctor to change it back I haven't had the bowel issue at all - my blood sugars are much less erratic too. This prescription my metformin mr was manufactured by Morningside (box was very similar to the Sukkarto) and on reading the added ingredients shellac was listed so I have returned them to my chemist who is now dealing with the surgery as they don't want to reissue the prescription!!
 
FWIW - when I changed surgeries a few years ago my brand got changed to Morningside's Sukkarto - it didn't dissolve consistently so I used to get these bouts of diarrhea as you described - if you read the pamphlet one of the added ingredients is shellac. My HBA1c rose consistently from that point with no changes to my LC diet until the one at Christmas alarmed my DN enough to put me on Forxiga too. However she did listen to me about the Sukkarto and since getting my doctor to change it back I haven't had the bowel issue at all - my blood sugars are much less erratic too. This prescription my metformin mr was manufactured by Morningside (box was very similar to the Sukkarto) and on reading the added ingredients shellac was listed so I have returned them to my chemist who is now dealing with the surgery as they don't want to reissue the prescription!!

My slow release is morningside Sukkarto, I will be speaking to my doctors to see what my other options are. Thankyou
 
Do you get any other gastric effects aside from diarrhoea? If it is as intermittent as every few weeks, I’m wondering whether it is food related? Not a low carb diet problem per se, but a reaction to certain foods/drinks? Perhaps noting down what you eat for a while would help to eliminate that possibility?
Goonergal beat me to it.
Before diabetes and before low carbing I used to get bouts of diarrhoea, and used to put it down to cream. BUT since low carbing my cream intake has increased but no diarrhoea. However I've had it twice after consuming wheat. It may be coincidence and just linked to the total number of carbs in that meal.
I'm not on any meds BTW.
Definitely worth looking at foods that might trigger it
 
I had really bad diarrhoea on a low dose of Metformin SR and gave up after a month, so not really what you’re asking, but my DN was very pragmatic about it and said “There’s no use struggling, there are plenty of other options.” I’m now on Linagliptin (+ low carb).
 
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