Tuesday, October 21, 2014

Tuesday, April 22, 2008 Zinnia, Community Member, asks

Q: Does metformin contain Lactose? Could this be triggering my lactose intolerance?

The metformin seems to create the same problems as my lactose intolerance, but on a much greater scale.  An article I read about Metformin mentioned lactic acidosis, which got me to wondering if Metformin contains lactose or something similar.  The obvious next question is whether or not there is a drug with similar efficacy, without that particular problem.

Answer This
Answers (4)
Vicki M, Health Guide
4/22/08 1:01pm

Hi Zinnia,


Lactic Acidosis doesn't have anything to do with lactose or being lactose intolerant. Lactic Acidosis is a condition where the body creates more lactic acid than it can dispose of. The metformin can sometimes hamper renal/kidney function, making it more difficult for the body to excrete the lactic acid causing the condition.


I don't see anything to suggest that the metformin is causing a lactose intolerance, but the side effects can mimic lactose intolerance with regard to gastro issues, diarrhea, IBS, gas, etc. You can read more about Metformin (generic for Glucophage) here in the drugs database.


Hope this helps! Take care and stay in touch!

Vicki M

jereann, Community Member
10/23/08 12:15am

My experience has been that metformin has created irritable bowel since first using it 6 months.  Suddenly I acquired extreme reactions that included diarrhea, gas, nausea. I lost 16 lbs in a matter of 2 weeks.  I finally realized that milk would cause the symptoms within an hour or so; therefore, I've got that out of the diet and the diarrhea ceases.  Then I stopped the metformin and the rest of the symptoms have ceased.  I am convinced that Metformin caused the lactose intolerence.  I began to take lactose and multiple enzymes (test showed I was low in amylase).  I believe my pancrease was altered by the metformin.  (Previously I had taken Avandia for 10 years until the warning of heart complications).  I am also taking lactibicillis bulgarius (sp) which may assist the lactose intolerence to reverse.  Currently I'm taking Glipizide alone.  I find I am slightly gaseous still so I'm not totally satisfied.  So may go to Januvia.  I wish Avandia could be modified...it managed my diabetes well, but gained weight.

resident6b, Community Member
11/10/09 8:50pm

I'm with you on this suspicion.  I was always a big dairy eater.  Then I had to go on metformin for PCOS.  I was on it for 3 years and the diarrhea and gas NEVER went away.  Seeing as they were reported side-effects I didn't think much of it.  Once I lost the weight I was supposed to, I was able to go off the drug.  Maintaining a pretty healthy diet I was still getting the stomach symptoms.  It turns out that I'm now very likely lactose intolerant.  I did an elimination diet and symptoms went away.  Added dairy back in, they came back.  Ate dairy with Lactaid, the symptoms were there, but less.  I really do think Metformin made me lactose intolerant.  Lactase (the enzyme that breaks down lactose) is produced in your small intestine and Metformin works in your small intestine.  I'm not sure what the full mechanism is, but it makes sense. 

marcus matthews, Community Member
7/15/11 10:48am



I had this very problem and went to the doctor, Most tablets use whey protein or similar as a bulking agent. SOME brands of Metformin use this and some don't. 


After some research with the pharmacist my brand was switched yesterday. Hopefully things wil now improve. 


My vitamins and other pills may also contain this so I am being ultra caeful until it's confirmed!


Answer This

We hope you find this general health information helpful. Please note however, that this Q&A is meant to support not replace the professional medical advice you receive from your doctor. No information in the Answers above is intended to diagnose or treat any condition. The views expressed in the Answers above belong to the individuals who posted them and do not necessarily reflect the views of Remedy Health Media. Remedy Health Media does not review or edit content posted by our community members, but reserves the right to remove any material it deems inappropriate.

By Zinnia, Community Member— Last Modified: 06/14/12, First Published: 04/22/08