Salt check

Yeah she should've stabbed her.

Yeah but only if you have a special demon or angel blade handy, otherwise you're just going to piss off the demon more!

Or the colt.

Use a fork bathed in holy water

It's a Supernatural thing. When you're possessed by a demon, holy water and salt burn your skin. You also can't go outside a circle of salt or a building if there's a line of salt in the way.

Ohhhh okay!! Thank you for informing me!!