• Guest - w'd love to know what you think about the forum! Take the 2025 Survey »

Dark Stool

jonnymuesli

Member
Messages
7
Location
Huddersfield
Type of diabetes
Type 2
Treatment type
Tablets (oral)
Hello everyone, glad theres sites like this to help me deal with things , i was diagnosed with type 2 two weeks ago , 2 days ago i was put on metformin 1x500mg for first week with breakfast. Ive taken 2 now and today after having no bother on the first day i had a bit of a rumbling stomach in the afternoon and went to the toilet and my stool was dark brown , never had that before , could it be me getting used to the medication ?
 
Have you taken Pepto Bismol recently? Just because that medicine can have that effect.
 
Hi Jonny,I have heard of Metformin causing Gastritis occasionally which if it causes some micro bleeding in your stomach,can lead to darker stools but usually you'd have unpleasant symptoms along with it and you haven't been on the Metformin very long but I'd keep an eye on that and consider speaking about this new symptom with a Doctor.
 
Ive been on it 2 days only , but i have a nurse review next week so i will mention it and see what tomorrow brings , thanks for the advice
 
Did you change your diet?
I've had a lot of gut issues - the "normal" range of poo is extraordinary. Blood in the stool causing colour change usually is very close to black. Think darker brown than coffee beans.

Still, if worried I'd ask a doctor. Small slow blood loss is no joke (says the guy who waited to seek help until his hemoglobin was 43 and he couldn't stand up/oxygenate anymore (normal:135-170))
 
Thanks for the replies and advice , and Gavin not changed too much in the diet , wholemeal for white bread , and tried to cut out carbs best i can , ive had a rumbly stomache on and off since starting the med but dont feel too bad , i have an appointment next week with the nurse so i will mention it , update on latest stool was fine thankfully .
 
@jonnymuesli If you have started taking vitamins or supplements with iron in, this could be one cause of the change.

It is strongly advised to get an urgent Dr's appointment at the first suspicion of blood in the stool.

Edit - You may like to google The Bristol Stool Chart, it's a wonderful point of reference!
 
I've just started metformin 6 days ago. My stools went black,tarlike,with blood. Urine also tinged with blood. GP thinks I'm having a rare reaction to the meds. I've been told to stop metformin ASAP while I have tests. Check with your healthcare professional.
 
Good evening @cocker0606 and welcome to the forum.
This is an old thread dating from 2017, but thank you for your contribution.
 
You must log in or register to reply here.
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn More.…