Overdosing on the mushroom Amanita muscaria, commonly known as fly agaric will not kill you per se but when ingested in significant amounts can lead to unsafe and possibly deadly situations should you over-indulge in it while alone.
This is a case of a white male in his thirties in western New York State who innocently thought he would go collect mushrooms to eat. Typical of many people who fall victim to accidental hallucinogenic overdose or even worse death due to eating mushrooms, this man had never taken a course in mycology.
He collected the fungi in a park on the south shore of Lake Erie, took them home, and had his wife make him a spinach salad with the fungi sliced and raw. According to the man's wife he had eaten approximately 20 small to medium sized mushrooms. By best estimates this was 40-60 times the minimum effective dose of 5-10 grams of fresh fruiting body in order to experience any psychoactive or somatic effects.
Having tasted this mushroom personally it is not unpleasant and tastes much like the common edible mushroom, Agaricus campestris, even a little sweeter. It is, therefore, not surprising that an uneducated person who likes mushrooms would eat a considerable amount.
Thirty minutes after eating, the man's wife saw him unconscious on the living room floor. The woman assumed he was sleeping as he spent the day outdoors and had just ate. Another half hour passed and the man was still "asleep" but the wife was distressed to see that he had urinated and yet had not moved. The woman attempted to wake her husband but he remained unresponsive and she called emergency services.
The man was admitted to the hospital his stomach was pumped and he was administered charcoal via an NG tube. The man remained unconscious for three days. On the third day he was responsive but altered and aphasic. The responsiveness was intermittent but became more prevalant from day 3 to 8 post-ingestion.
During the responsive periods in this the man became more animated and less aphasic. He would sexually harrass and make lewd suggestions to nurses. He became animated enough at a point on the fifth and sixth day that he was sedated and put in restraints as he attempted to remove the N-G tube. He was unable to recognize his wife or that he was in a hospital until the seventh day. The man was finally able to eat on his own the nineth day and the N-G tube was removed.
The man stated he had no recollection of the first 48 hours. Upon becoming aware he had overwhelming feelings of strength and overwhelming somatic hallucinations such that he was unable to move. He stated he was afraid he would break anything he touched including his bones as he thought his muscles were so strong he would break them too. He said the feeling of superhuman strength was present much of the time along with increased libido.
On the tenth day the man was normal albeit fatigued. The man recovered completely and experienced no further complications. It should be noted that this is an extreme case yet had the man been alone he could very likely have died of dehydration as he was unable to eat or drink for several days. Examination of the stomach contents by a mycologist determined that the mushrooms the man had eaten were A. muscaria based on the spore anatomy.