Back row Tom Brown has not yet recovered from the dead leg he picked up against Munster and Ben Castle Jamie Smith and Will Harries are still unavailable.
There is some good news from the physio room with centre Ashley Smith back in full training and hoped to be ready for the Galway trip.
"I know on paper the injury list looks daunting, but that's the way it is in rugby," said Dragons Head Coach Darren Edwards.
"Players like Adam Hughes got their chance covering for injury and that opportunity enabled him to cement his place in the Dragons line-up. Potentially having Ashley back is a big boost and we will deal with things as they come.