Gregory House commonly uses Vicodin for chronic pain in House M.D.
Vicodin is a brand-name prescription combination of hydrocodone and acetaminophen. In the series, House takes it to manage severe chronic pain caused by a damaged right leg. His dependence on the medication is a recurring part of his character and creates professional, legal, and personal consequences.
House’s use of Vicodin is not simply a background detail. Colleagues challenge his prescribing and consumption, and several storylines focus on attempts to stop, regulate, or conceal his drug use. The show also depicts withdrawal and addiction as sources of conflict.
The brand name is often generalized as “painkillers,” but Vicodin is the specific drug repeatedly associated with House. OxyContin, codeine, and tramadol are different medications and are not the canonical answer to this question.