I stopped all other herbs/meds and I have just started taking 5-htp and St John's Wort along with vitamin D, omegas and vitamin B complex. So far it seems to be helping.
I think the crawling bugs feeling is heightened by anxiety and the mind can also play tricks so if you think a dirty sheet may be infected with bugs that sensation can manifest just by thinking it. Also thinking you are infected by bugs will increase anxiety as you try to clean everything and imagine them crawling under your skin! I know when I first started researching about morgellons on the internet all the theories of being infected by nanobots etc stressed me out big time which also exasperates anxiety.