A round white 6.0mm pill with the imprint 54 196 on the front, and 4 on the back of it is 4mg of Hydromorphone hydrochloride (made by Roxane Laboratories). It is also sold under the brand name Dilaudid.
Hydromorphone hydrochloride is a narcotic analgesic that is used to treat pain, cough, chronic pain, and anesthetic adjunct. This prescription-only medication may pose a risk to an unborn fetus, and should be used only under a doctor's supervision.
Abuse of this drug may lead to psychological or physical dependence, in fact a recently recovering 23 year old addict lost his college scholarship due to abuse of Hydromorphone hydrochloride.