Poison
Plenty of the delicious plants and mushrooms in the UnReal World are perfectly safe to eat snacks just waiting for a wandering adventurer to pick them up and eat them. Not all flora make for healthy snacks though, as some of them are quite poisonous. Fortunately for the culinary adventurer, poisons can often be removed through blanching, using a pot and some water with the "Boil / Herbal beverages" cookery option. Unfortunately some plants and mushrooms are just not meant to be snacks and remain poisonous even after blanching.
Effects
The effects of poisons can be irritation in stomach and throat, nausea, hallucinations, illness, or death. The ill effects wear off after a day or two, quite permanently in the case of death.
Poisoning
Poisoning is the inevitable result of ingesting a poisonous plant or mushroom. It cannot be treated by the physician skill. Instead, treatment needs to be asked from a sage or a shaman. Some herbal remedies may expedite the passing of poisons from ones body.
In the case of deadly poisoning, asking a sage for healing is the only chance of survival. In such a situation, it is advised to beg the sage for healing multiple times, and to be awake 8 a.m. when the game's morning check happens. Even then, the odds of survival are only 1 in 3. One may try to improve these odds by praying to one's deity of choice.