House is addicted to Vicodin during much of House M.D.
Vicodin is a brand name for a prescription combination of hydrocodone and paracetamol, also called acetaminophen. In the series, House uses it to manage severe chronic leg pain caused by an infarction in his quadriceps muscle.
His dependence on the drug is a central character conflict rather than a minor medical detail. House’s colleagues and supervisors repeatedly question whether Vicodin affects his judgment, behavior, and ability to work safely. The show depicts periods of withdrawal, relapse, and attempts at treatment.
House’s pain and addiction are fictionalized for drama, and the exact medical circumstances are not a guide to real treatment. The character’s reliance on Vicodin also reinforces the series’ theme that extraordinary diagnostic talent does not remove ordinary human vulnerability.