Codeine is a morphinane alkaloid found in the opium poppy, Papaver somniferum var. album; has analgesic, anti-tussive and anti-diarrhoeal properties. It has a role as an opioid analgesic, an antitussive, an opioid receptor agonist, a prodrug, a xenobiotic, an environmental contaminant and a drug allergen. It is an organic heteropentacyclic compound and a morphinane alkaloid. It is functionally related to a morphine. It is a conjugate base of a codeine(1+).