Codeine is the most widely used, naturally occuring narcotic in medical treatment in the world. This alkaloid is found in opium in concentration ranging from 0.7 to 2.5 percent. However, most codeine used is produced from morphine. Codeine is also the starting material for the production of two other narcotics, dihydrocodeine and hydrocodone.
Codeine is medically prescribed for the relief of moderate pain and cough suppresion. Comparewd to morphine, codeine produces less analgesia, sedation, and respiratory depression, and is usually taken orally. It is made into tablets either alone or in combination with aspirin or acetaminophen. As a cough suppresent, codeine is found in a number of liquid preperations. Codeine is also used to a lesser extent as an injectable solution for the treatment of pain.