Morphine is a morphinane alkaloid that is a highly potent opiate analgesic psychoactive drug. Morphine acts directly on the central nervous system (CNS) to relieve pain but has a high potential for addiction, with tolerance and both physical and psychological dependence developing rapidly. Morphine is the most abundant opiate found in Papaver somniferum (the opium poppy). It has a role as an opioid analgesic, a mu-opioid receptor agonist, a plant metabolite, an environmental contaminant, a xenobiotic, a vasodilator agent, an anaesthetic, a drug allergen and a geroprotector. It is an organic heteropentacyclic compound, a tertiary amino compound and a morphinane alkaloid. It is a conjugate base of a morphine(1+). It derives from a hydride of a morphinan.