Rashes In Groin Area, Maintain Hygiene, Permecthrin Cream, Stromectrol Pills. STD?

My boyfriend and I both broke out at the crease between our buttocks and leg. This has been going on for 2 months. We have several other areas of breakouts. We ve gone through all of the housecleaning, bagging clothes in black trash bags, etc. We wash clothes every day, including bed linens and towels. We ve both been Permecthrin Cream and have taken 2 doses of Stromectrol pills . We also used the Naturasil products to no avail. We ve been to 2 doctors, all say it s scabies mites, but none have run a test. If it is scabies mites, are there other alternative meds that are not toxic? Thanks.