I would assume it would be less poisonous as the potency of the poison may drop off depending on the poison. Water soluble poisons that have a mix of water in them, those might get more potent in poison levels - but less effective due to delivery method being limited.
I've never seen the actual comment... however early I come it's deleted... Even this time I less than an hour after the comment was posted. But... deleted. LOL IDK why I'm making this comment.
Less, there was an incident in ww2 where a spy was given poisonous pills to take in case he was captured, and he took them because he was captured. They were expired so he was just, SUPER sick.