How do you prevent NPCs to cast a spell you added to the game?

[wholegrain]

I see the option to remove spell books from the leveled list, but I don't see anything that allows me to prevent NPCs to cast the spells.

[Gameplayer]

NPC's don't normally cast mod added spells though.

Normally most mod users have to use another mod that gives the NPC's spells like a proccor patch. 

I think ASIS does this.

 

If you added a spell they should not normally use it.

If you altered an existing spell you may have to remove it from a listing or specifically from each NPC.

 

Again if you altered an existing effect or spell, I'd say your best bet is to remove that edit.  You would be better off Duplicating the spell or effect and making sure it had a unique Editor ID and name it so you can find it quickly in CK or TesVedit.