All of the sudden my stool has turned black. I took pepto bismol tablets on Friday and today is Monday. Could this be it? I have taken pepto tabs before and it hasn't done this. I also drank alcohol more than usual this weekend so could that have any affect? My stomach does not hurt, and my poop is normal consistancy, just very very dark. Any suggestions as to what it may be?

Darkening of the stool is a possible side affect of Pepto Bismol.

I would just keep an eye on the color of your stool over the next few days.

It is well known -- but I alway wondered why it's not listed on the container as a side effect. The bismuth in Pepto Biismol will make your stool dark to even turning black.

It certainly is alarming when you first see it particularly if you have been bleeding because of hemorrhoids or an anal fissure.