Ever got menthol on your lips or up your nose. Now imagine that up yer arse - it'll produce an irritant effect from hell & make you want to empty your bowels quite badly (glycerine/soap is the ingredient in most suppositories designed to counteract constipation as they mildly irritate the gut wall and promote
expulsion. Menthol is a hel of a lot more irritating) If you want to use anything, ...