Ibotenicacid is a toxic, possibly psychoactive compound present in Amanita muscaria and Amanita pantherina.
When ingested, a small amount of ibotenicacid is decarboxylated into muscimol, causing an initial drowsiness, followed by a four hour long excited state.
The Ibotenic acid/muscimol found in Amanita muscaria and Amanita pantherina was used by Siberian shamans as a sacrament.
Muscazone is readily prepared from ibotenicacid (Chilton & Ott, unpublished; Goth 1967), may be an artifact of isolation procedures, and is of dubious psychoactivity.
A second user ingesting the urine of the first, would cause some of the ibotenicacid to be decarboxylated to muscimol during digestion, producing inebriation when the muscimol was absorbed; and the bulk of the ibotenicacid would be re-excreted in his urine in turn.
Thus a 100 mg dose of ibotenicacid might potentially represent four or five 10-15 mg doses of muscimol, and Steller's 1774 report that one dose of mushrooms could be recycled through four or five persons is certainly feasible.