Dilaudid is the brand name for the popular generic drug named as Hydromorphone. It is categorized under the opioid medication drugs that are sometimes also called as a narcotic drug. This drug is used to treat moderate to severe pain that may be taking place in a human body. There can be other purposes of Dilaudid that are not mentioned here. Although this drug does not severely affect your body, it is better if you take a recommendation from a health expert.