Papaver somniferum
Codeine is found in concentrations of 1% to 3% in opium prepared by the latex method from unripe pods of "Papaver somniferum". The name codeine is derived from the Ancient Greek (, "poppy head"). The relative proportion of codeine to morphine, the most common opium alkaloid at 4% to 23%, tends to be somewhat higher in the poppy straw method of preparing opium alkaloids.