Ah , dear Sunshine - how I wish I have all of the answers :( and offer ultimate help to all that are here. I can only speak from my own experience and from what I read.
I would try what I suggested - pitting first vaseline outside and a lot of it. Spread it well in crevices and all over the tags on both sides. Than use tube applicator and apply D. inside. Pull applicator out very slowly in squat position over the mirror. Have q-tips ready by your side and immediately wipe it all
without smearing all around. Use 10 q-tips if you need to. Than when all is off, put again some vaseline to make physical barrier if anything seeps back later.
If you continue using D. it can not harm you in any way if it continues to itch even with careful application. The itch will stop as soon as you stop D. , if that is what worries you - that it might stay ? No, it should go away by discontinuation in a week or two. How about you try this trick with Vaseline and if it does not help ask for Nefedapine (sp. ?)
Also, send me your address by PM and I will send you Miralax if you have no means of getting it !
PS: Is your D. cream just that or has anything else added in, like lidocaine etc. ???
All the best and I hope that Vaseline trick will work