I'd rather use either castor oil or hemp seed oil in a lip product if you don't go towards shea and cocoa butter due to consistency. Now, both oils can be allergens, however most of those who are allergic to (tree) nuts do not have a reaction to hemp seed oil. There are people who are allergic to the cannabis plant itself, but that group is much smaller than the nut allergy one. So my vote goes to hemp seed oil :)