About 70% of morphine is used to make other opioids such as hydromorphone, oxycodone, heroin, and methadone. It is a Schedule II drug in the United States, Class A in the United Kingdom, and Schedule I in Canada.orphine is a precursor in the manufacture in a large number of opioids such as dihydromorphine, hydromorphone, hydrocodone, and oxycodone as well as codeine, which itself has a large family of semi-synthetic derivatives.