If Mifepristone is unavailable, a misoprostol-only regimen may be substituted. Mifepristone is an antiprogestin that has a higher affinity than progesterone for binding to the progesterone receptor but does not activate it. Buy cheap MTP kit online from DayNightHealthCare Store. This is a combo of Mifepristone and Misoprostol kit which help for easy and safe abortion at home.