This Alchemical substance causes the target to hallucinate. They will see all kinds of oddities and other strange things for five minutes, including odd creatures or memories. The target will probably be aware that they are under the effects of a poison.
Hallucinate is a role-play effect which affects all the user’s perceptions, not just their sight. A blindfold might block out visual hallucinations (or it might not), but it would not block out the character’s other senses, which are also affected by the Hallucinate. They will experience unusual sensations across all senses, such as feeling water flowing over your skin or a sour taste in your mouth, for its duration. The exact ‘phantom’ sensations are up to the player, and may include things that are pleasant, scary, or anything in between.
When under its effects, Game Abilities can be used, but the player will most likely use them against imaginary creatures and may even read potion labels and scrolls incorrectly in their delirium.