What drug is Dr. Gregory House addicted to in House M.D.?

Dr. Gregory House is addicted to Vicodin in House M.D.

Vicodin is a prescription painkiller containing hydrocodone and acetaminophen. House uses it to manage chronic pain associated with the infarction and muscle damage in his right leg. The medication becomes a major part of his characterization and creates repeated medical, ethical, and professional problems.

The show does not present House's dependence as a simple personality quirk. Several storylines depict withdrawal, relapse, rehabilitation, and the effects of addiction on his judgment and relationships. His colleagues, particularly Wilson and Cuddy, repeatedly confront him about the risks of continued use.

Vicodin is sometimes confused with morphine or oxycodone because all are opioid pain medicines, but the named drug associated with House is Vicodin. The series uses the drug as a recurring plot element rather than suggesting that it explains all of House's diagnostic abilities or behavior.