If someone drank poison, could you tell by searching through their poop?

Question: If someone drank poison, could you tell by searching through their poop?
- Keywords:
  drank,
  poison,
  poop
Asked by Emma The Penguin Lover to Áine, Ciarán, Eoin, Lydia, Victoria on 12 Nov 2014.
- Ciarán O'Brien answered on 12 Nov 2014:
  
  For any poison you eat or drink, yes. your intestines would absorb the poison into the blood stream, but they wouldn’t absorb all of it, and you’d be able to find traces of it in the poop of someone who had been poisoned.
  
  Even if the poison was just an overdose of something we eat regularly, you could tell from the poop because there’s be very high levels of that food in there.
  
  This wouldn’t work for any poisons you didn’t eat or drink. If it was injected straight into your blood, it would never show up in you poo.
  
  Note: Don’t go trying to poison anyone. It’s very impolite and you won’t get invited to parties.

Question: If someone drank poison, could you tell by searching through their poop?