Serious symptoms do not always occur immediately after eating; often not until the toxin attacks the kidney, from minutes to hours later. In rare cases, symptoms leading to death may not appear for days after eating a poisonous mushroom. Symptoms typically include:
* Lethargy
* Headache
* Dizziness
* Cold sweat
* Vomiting
* Sharp abdominal pains
* Jaundice
* Severe diarrhea
If treated promptly, death can usually be avoided. Otherwise, with some toxins, death could result within a week or a few days, if the species ingested is a potent one.
http://en.wikipedia.org/wiki/Poisonous_mushroom