House M.D. identifies Vicodin as Gregory House’s regular pain medication.
Vicodin is a brand name for a prescription combination containing hydrocodone and acetaminophen. In the series, House uses it to manage chronic leg pain caused by an infarction in the quadriceps muscle of his right thigh. His dependence on the drug becomes a recurring part of the character’s medical, ethical, and personal storyline.
The medication is not simply a character accessory. House’s use affects his judgment, relationships, employment, and treatment decisions, and several story arcs examine withdrawal, relapse, and attempts to obtain pain relief.
Vicodin is often confused with other opioid pain medicines, including oxycodone products such as OxyContin and Percocet. Those drugs are not the regular medication identified for House in the series. The question asks for the named medication, not the underlying cause of his pain.