Buy a safe, and lock all your knives in it! By the time you have tapped in the combination, the urge might have passed.
Go to Narcotics Anonymous (NA) a 12--Step Program for ALL types of ADDICTS. Cutters go there frequently. Their program works, I've seen it! NA is free and all over town at different times of the day, so you can get to a meeting today if you truly want to quit! Best wishes.
call your doc-find support groups-- get a sponsor--God Bless