Gregory House is addicted to Vicodin in House M.D.
Vicodin is a prescription combination of hydrocodone and paracetamol, also called acetaminophen. In the series, House uses it to manage severe chronic pain caused by a past infarction in the quadriceps muscle of his right thigh. His dependence on the drug becomes one of the show’s central personal and professional conflicts.
House’s drug use affects his judgment, relationships, employment, and medical license. Several major storylines depict attempts at rehabilitation, periods of sobriety, relapse, and the consequences of obtaining or misusing prescription medication.
Viewers sometimes name hydrocodone alone, but hydrocodone is the opioid ingredient rather than the brand name used most often in the show. The canonical answer is Vicodin, the medication House repeatedly carries and takes.