DILAUDID ORAL LIQUID and DILAUDID 8mg TABLETS contain hydromorphone, which is a potent Schedule II controlled opioid agonist. Schedule II opioid agonists, including morphine, oxymorphone, oxycodone, fentanyl, and methadone, have the highest potential for abuse and risk of producing respiratory depression.

Hydromorphone is a pure opioid,^[1] a semi-synthetic hydrogenated ketone derivative of morphine that has been available clinically since 1920. Structurally, hydromorphone derived from morphine in the modification of the hydroxyl group in the carbon 6 to a carbonyl and the absence of a double bond between the carbon 7 and 8. Due to these modifications, it presents a very high potency and comparable side effect profile to the parent compound.^[2] Even though hydromorphone does not present a 6-hydroxyl group, it is categorized under the family of phenanthrenes and it is considered a chemical under the schedule II (medical purposes with high addiction potential).^[3]

The first reported approved product containing hydromorphone in the form of hydromorphone hydrochloride was developed by Fresenius Kabi USA and FDA approved in 1984