“Insensitive” is the House M.D. episode featuring a patient who cannot feel pain. It is the fourteenth episode of the third season and centers on Hannah, a teenage girl with congenital insensitivity to pain.
Because pain normally warns the body about injury, Hannah's condition creates unusual medical dangers. The diagnostic team must investigate why she lacks pain sensation while treating the immediate problems caused by injuries that would normally be noticed.
The episode also develops relationships among House's team members, especially as the doctors confront the emotional and practical consequences of Hannah's condition. Its title refers directly to the medical symptom rather than to House's famously harsh personality.
“No Reason” is the season-three premiere, “Safe” is a season-five episode, and “The Itch” is not the title of this case. Those nearby titles can make episode identification more difficult.