House is frequently shown taking Vicodin in House M.D.
Vicodin is a prescription painkiller combining hydrocodone and acetaminophen. In the series, House uses it to manage chronic leg pain caused by an infarction in his quadriceps muscle, an injury that also leaves him with a limp.
His dependence on the drug is a recurring part of the character's story rather than a minor medical detail. Colleagues repeatedly challenge his use, and several plots examine withdrawal, addiction, concealment, and the effect of pain on his judgment.
Viewers may confuse Vicodin with other opioid medicines because many dramas use similar names. House's signature medication is specifically Vicodin, which was also the brand name associated with hydrocodone and acetaminophen.