Dr. House regularly takes Vicodin in House M.D.
Vicodin is a brand name for a prescription combination of hydrocodone and paracetamol, also called acetaminophen. In the series, House uses the drug to manage chronic pain caused by an infarction in the quadriceps muscle of his right thigh.
His dependence on Vicodin is a continuing part of the character's story rather than a minor medical detail. Colleagues repeatedly challenge his use of the medication, and several storylines examine addiction, withdrawal, and the effects of pain on his judgment and behavior.
Vicodin is not the same as morphine or oxycodone-only products. Its exact formulation and legal status have varied by country and over time, which is why the brand name is the clearest canonical answer for the show.