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Metformin not digesting?
maragayle posted:
This is probably going to be TMI, but this past week I've noticed my Metformin in my stool. Like the whole, complete undigested pill. I switched a month or two ago to the extended release version. I take one 750mg pill in the morning and one in the evening. I've only noticed this happening with the one pill. Any one else have this issue? It's as if it wasn't digested at all!
ORANGE54140 responded:
I had this same thing! I freaked out thinking I wasn't even getting any of the medication. I recently asked my doctor (I too am on XR form, stomach couldn't handle regular form). She said it was just the coating, as it doesn't digest, that it's normal...not to say too much TMI but it looks like a puffed up cotton ball in the toilet!
maragayle replied to ORANGE54140's response:
I've been paying closer attention since I first noticed it. (Not really something you usually pay much attention to!) Sometimes it's there, sometimes it's not. It's really strange! That was my concern, too. Though, I've been having side effects from it still, so I think I'm still getting the medication! The side effects are nowhere near as bad as the regular version of Metformin, but they're still present. Thanks for the reply!
BeverlyLReed responded:
I am on metformin HCL 500 mg (5 a day)... I noticed that my pill.. once in a while doesn't digest, it comes out when I go the bathroom... was there a medical reason why this happens? The pill is whole, only it looks a little bigger. This is not a capsule, it is a pill. Does anyone know if this happens what it means?
curiousnmo replied to BeverlyLReed's response:
I have never had that problem with the extended release pill. I have actually had way better bowel movements since I switched to it. Weirdly enough.. the regular kind gave me diarehhea. tmi sorry but it's weird it regulated me lol
BeverlyLReed responded:
I haven't really gotten a straight answer on this one. I take 2000 mg of metphormin a day... normal pill... every now and then the entire pill will come out as well. It's isn't the outside of the pill.. it's the entire pill... I just figure that maybe my body doesn't need it and its rejecting it... I will be asking my doctor AGAIN next week about it...
maragayle replied to BeverlyLReed's response:
I switched back to the regular version of Metformin instead of the extended release. All is well now.
Yanis replied to maragayle's response:
Hello everyone,

Seeing a pill in your stool can be quite common in the case of extended release medications.

There are usually two forms of extended release pills/tablets:

First is the hard-shell type. Usually a polymer vessel with a microscopic hole on one side and a porous membrane on the other. So the acid/liquids in your stomach permeate through the membrane and "push out" the drug via the hole.

The other, which I suspect Metformin extended release is based on is a vessel made of insoluble material with the drug embedded inside, so when the pill is soaked, the drug comes out slowly.

Usually both types pass through the GI tract intact, minus the drug. In fact their mechanism of action is based on this fact. That is the reason why you should never cut an extended release tablet/pill, that would defeat the purpose.

So I wouldn't worry to much seeing them in your stool. The drug they contain has probably been released and doing it's job properly. I myself take a few pills, and three of them are of either type, and I do see them from time to time in my stool.

Talk to your pharmacist for more information, he/she is the one that has all the information you need about your meds.

You can also read the Wikipedia page on time-release pills here: ?

Hope this helps.
buba3840 responded:
I have been having the same problem. I find it in the toilet hours after I've taken it. It seems somewhat smaller but it is not digesting. The pharmacist told me I am probably missing an enzyme but how do I find out which one. I take enzymes now.
An_263003 replied to BeverlyLReed's response:
Yes, the reason I saw your article is because I am having the same problem. I'll be asking my doc. because after this happened to me I started feeling very dizzy and could not hold my head up. I was thinking that the pill had not been doing it's job for a while.

I'll respond after I talk with my doc.

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