Please Daven - For How Long?

Very often we hear of cholim and are asked to daven but don't receive updates as to their condition. Since it happens that the choleh no longer needs our tefillos [either because they healed or because they went to a place where there is no illness...] - should one still daven even if we don't know if the choleh is still a choleh? One problem is that it might be a תפילת שווא - a prayer for nought. Another is that if one mentions the choleh in the רפאנו bracha of shmone esrei and the person is no longer a choleh it would be a הפסק.

This is discussed in many sources and the consensus of the poskim is that one should still daven [and even mention the name during shmoneh esrei]. Praying for someone's life - even out of doubt - trumps all other factors.

That is the short of it. See among other sources the Ramat Rochel of the Tzitz Eliezer in Simman 18.

PS - Since רח"ל there are so many cholim I am not sure that it is practical to daven for every choleh עד ביאת גואל....  But we should be מתחזק in davening at least once for every choleh we hear about.