Serious
Muscarinic syndrome
Muscarine
Onset after the meal
15 minutes to 2 hours
Inside six hours, which is the reassuring side of the line, with one qualification: a mixed wild meal can produce an early reaction that hides a late one.
Attacks
The parasympathetic nervous system
What it does
Sweating, streaming eyes and nose, heavy salivation, blurred and pin-point vision, abdominal cramps, a slowed heart and, in serious cases, difficulty breathing. Clinicians remember it by the initials SLUDGE.
How it runs
Usually resolves within a few hours to a day. Deaths are rare but have occurred, chiefly from cardiac and respiratory effects in the very young, the elderly and the frail.
Treatment
Atropine is a specific and rapidly effective antidote, which makes this one of the few mushroom poisonings with a real answer. Get to a hospital and say the word muscarine.
The catch
Confusingly, the fly agaric contains almost no muscarine despite the name of the compound coming from it. The species that actually cause this are small white Clitocybe and brown Inocybe species that nobody meant to eat.
Species that cause it
This is reference material, not clinical guidance and not a substitute for a poison centre. If somebody is unwell after eating a wild mushroom, call one now, tell them the interval between the meal and the first symptom, and keep an uncooked specimen.