Brief Answer:
Possible bile problem , further examinations

Detailed Answer:
Hi Dear user ! Thank you for posting your question here .
Grey -colored feces are cause by the bile flow problem .You don't have enough bile in your feces
.
But first have to explain that is important to know if you have grey feces once in a while of you have it every time ..
If you have grey feces once in a while , it is not a problem but if it's every time you have a bowel movement it's a problem .
In your condition could be:
- liver problem (if the grey feces started after your took Remeron ,it is possible that is a side effect of the drug .
-if you have other symptoms like : pain in uper-right abdomen or between the shoulder that sometimes gets worse after eating fatty food , ,itching, yellow skin , could be a gallestone problem or other biliary tract obstruction.

I suggest to do some blood test to check your lives enzymes , ultrasound. According to The result your doctor will discuss with you about the treatment or change the medication. Please follow these advices .

Hope It is helpful!
If you have any other clarifications I will be happy to help or you can close the discussion .
Wish you good health .
Dr Rudina

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