Actually, the medicine she gives you isn't always poison. It can be 1 of 3 things: poison (like you said), sleeping drugs, and medicine that heals you 25 HP (on hard difficulty, can't rememer if it's more on easy/normal). The poison can obviously kill you, but the other 2 can't. Falling asleep with the sleeping drugs takes you to spawn room (which has been locked) where she is sleeping and you leave by finding the key. She looks cute asleep in my opinion so I recommend trying to get the sleeping drugs just once lol. She wakes up and starts chasing you when you unlock the door with the key. I think I saw someone say the medicine she gives you has a 50% chance of being good, and 50% chance of it being bad, but I don't remember where that was. Maybe it was on discord? Can't remember, but the chance of it being bad isn't ridiculously high judging from my own experience with the game. I forgot to mention this in my previous reply, but don't run after stepping on glass. Wait or walk for a few seconds after stepping away from the glass. Running makes you take A LOT more damage than if you simply walked. It's actually possible to lose as little as 5 HP or so (IIRC) on highest difficulty if you just take it easy instead of rush. Contrary to what seems like popular belief, she is rarely so close to you that you can't afford to walk for a few seconds after stepping on glass rather than run. Running after stepping on it just because you are in the middle of a chase is a super common mistake from what I have seen, and a mistake that I want to end as it can really make one lose the gameplay lol.
I haven't done much with my profile so I hope it didn't bore you lol.
Lire is a pretty good indie horror game but it could use some refinement, though I suppose that is to be expected of a demo. I think you should give it a try. I won't spoil it, but the monster in the final puzzle area gave me major goosebumps I haven't felt since playing the horror game "DreadOut" years ago lol.