Drooling will be mediated by two factors: (1) the presence of an irritant which induces salivation and (2) the inability to flex the muscles of the mouth and induce swallowing.

Generically speaking, there are three sorts of gags: (1) obstructive, (2) intrusive, and (3) spreader. Obstructive gags seal the mouth; think wadded up undies or duct tape. They're a bad idea since they don't induce drooling and might asphyxiate your partner. Intrusive gags strap across the mouth with an appendage inserted into the oral cavity; think penis gags. They will force the jaws apart, preventing swallowing, and will introduce an irritant. If you're going to use such a gag, make sure that the intrusion is shallow since either triggering a gag reflex or obstructing breathing might result from a deep intrusion. Spreader gags hold the jaws apart while leaving the front of the mouth partly or wholly open. Think ring gags or wiffle gags, a highly perforated version of a ballgag. (There are also dental ones that strike me as pricey and a bit excessive. Either a ring or wiffle will keep her from closing her mouth or swallowing, will be irritating and would pose no risk to breathing.

Small amounts of a topical oral anesthetic, such as Anbesol, on the lips or tongue might complicate her ability to control her reactions but I haven't confirmed that.

Bottom line: safety, safety, safety! As someone who has near passed-out from a vocal chord spasm - bad reaction to a doctor-prescribed inhaler - I'm really cognizant of the fact that breathing is awfully important and not a process to be interfered with.

S.