Getting straight to the point, I need a poison which is:
- water soluble
- slow acting (three hours would be good, or if such a poison even exists, about a week would be optimal)
- is colorless/odorless/tasteless
- is deadly in small quantities
- makes the consumer visibly ill fifteen to thirty minutes after drinking/eating/inhaling (e.g., vomiting, fever, change of skin tone)
(Have tried Google searches, etc. on "slow acting poisons," "liquid poisons," "poisons used in assassination" and similar.)
Edit: the setting is modern fantasy, and the poisoner has access to pretty much any poison they want, at any cost.
Edit again: thanks to everybody who replied! I think I'm going with Polonium-210 :)
