Minimal exposure + asymptomatic at least 12 hours after exposure can likely be discharged.
Admit all symptomatic patients!
If evidence of deliberate self harm, place on hold and consult psychiatry
Organophosphate toxicity
Carbamate toxicity
Salicylate toxicity
Mushroom toxicity, especially:
Chlorate toxicity
Amanita muscaria
Thallium toxicity
Inocybe