Sort of.  Most creatures cannot digest empathetic energy, and so the purified love regurgitated by a Queen overwrites the pony’s physical being to allow it to be digested.

This, of course, leads to the pony being changed.  Usually the process takes some time, as the love is in such a refined state that it can last a typical changeling a rather long time.  In these cases the converted pony is put into a stasis pod to ease the change along.  In other cases the influx is powerful enough to forcibly convert the pony within moments.