From a priest reader:
Have you ever come across a vessel designed for bringing the Precious Blood to the sick? I have a parishioner to whom I regularly bring communion, but she is now on an absolutely no gluten diet, so even low gluten hosts are out of the question.
A friend of mine said he had seen a priest with the kind of vessel I am looking for, so I know they exist. Do you know where I might find one?
If such a vessel exists, don’t know about it.
It usually is forbidden to reserve the Precious Blood. I understand that some of the Precious Blood may be reserved for Communion for the sick only. In 1967 there was an instruction Eucharisticum Mysterium as a heading "Communion under the Species of Wine Alone". There we find that
41 … If, however, Mass is not celebrated in the presence of the sick person, the Blood of the Lord should be kept in a properly covered chalice and placed in the tabernacle after Mass. It should be taken to the sick person only if contained in a vessel which is closed in such a way as to eliminate all danger of spilling. When the sacrament is administered, that method should be chosen from the ones given in the Rites for Distribution of Communion under Both Kinds which is most suited to the case. When Communion has been given, should some of the precious Blood still remain, it should be consumed by the minister; he will also carry out the usual ablutions.
I don’t know how this would be done, except perhaps with a small glass vial designed to be sealed very tightly. The Precious Blood would then be administered directly by the priest from that vial, rather than transferred yet again to another vessel.
I would be happy for correction on this if I got it wrong.
It seems to me that this could open up the possibility of all kinds of abuses, first through simple accidents on the part of priests or deacons and then by laypeople helping with the sick. This should be rare indeed and ad personam according to circumstances and done only by priests, if possible.
I believe the best solution is occasionally to celebrate Mass in the sick room and give Communion with the Precious Blood on the spot.
Note that a priest posted below on his experience. He also used an eyedropper.