Bitter, green liqueur derived from Wormwood tree extract
Active ingredient: thujone, which antagonizes GABA-A receptors (now thujone concentrations are thought to be too small to pose any danger to patient)
Illegal in most countries
Absinthe toxicity
Serotonin-Like Agents
Jet Propulsion Fuel 8 toxicity
Lysergic acid diethylamide 
Bath salts toxicity
Psilocybin 
Blister chemical agents
N,N-Dimethyltryptamine 