I have a character ("A") who is poisoned with a lethal dose of atropa belladonna, AKA deadly nightshade (opens in a new window). The poisoner is an amateur so he uses only enough to get him very sick but not dead. I was thinking he could dose A's red wine with the juice from the berries of the plant, which could mask the taste while delivering a near-lethal dose. He drinks the wine and eventually begins to convulse, which is one of the symptoms.
A is taken to a hospital where he is unknowingly followed by his poisoner ("T"). As A is treated, T slips larger doses of belladonna into his food and drink.
My question is this: once T doses A with a suitably lethal dose, how long does A's doctor have to save his life? A's doctor ("H") doesn't know what's causing his symptoms early on and can only treat the symptoms. What sort of timeline am I working with?
Also, if you have any other nitpicky things about my use of the poison, please pick away! Constructive criticism = good.