Glaucine is an alkaloid found in several different plant species such as Glaucium flavum, Glaucium oxylobum, Croton lechleri and Corydalis yanhusuo. It has bronchodilator and antiinflammatory effects, acting as a PDE4 inhibitor and calcium channel blocker, and is used medically as an antitussive in some countries. Glaucine may produce side effects such as sedation, fatigue, and a hallucinogenic effect characterised by colourful visual images, and has recently been detected as a novel recreational drug.