in what episode does house cut himself? it was in S2 i think, when he had to give up the drugs..

The episode you are referring to is "Merry Little Christmas" in season 3. Wilson has made a deal with detective Tritter so House has a choice: jail or rehab. Dr. Cuddy and Wilson take away House's pain meds. The pain or the detox gets to be too much so House cuts himself to release endorphines. Endorphines relieve pain.

well u have to be specif cause he detoxed a couple time but the oe u r thinking of is probably detox in season four or five