Can Gastrografin (contrast medium) motive black tarry diarrhoea?

My mother aged 82 who has have a previous CA sigmoid colon, has simply been for a CT check up and today the time after scan and the contrast medium, she have tarry loose stools. I know it can cause diarrhoea, but be shocked to find out it was black. This is what she have before surgery 15 months ago. She also have a slight rise in her Cancer attraction blood tests to 8.4. She have a reversal ileostomy two weeks after initial surgery.Can Gastrografin (contrast medium) motive black tarry diarrhoea?
Black tarry stool is usually a sign of GI bleeding. She should be watched closely for signs of shock / blood loss (elevated heart rate, ashy skin, rapid breathing, mental status change, anxiety, thirst) and should be evaluated by a physician immediately. Get her to the ER or urgent comfort.
I agree with the poster above. Go to the ER or the urgent supervision. I think if black tarry stools be to be expected after the CT they would have mentioned it when they explained the oral exam to you...
You are right, this is unlikely to be a side effect of the gastrografin. Black tarry stool is usually melena=changed blood. This may be quite serious and you should want medical advice hurriedly!