Medicants are race of constructs that were created long ago by the Progenitors to act as self sustaining automated medical units, they were created to free doctors up for the front lines and were used mostly in hospitals and family practices.
The medicants somehow managed to survive their creators destruction and while they will still aid those that are injured theire programming has become corrupted in that any strange mutations that they come across [especially espers] will be captured and taken back to their red and white progenitor battle cruisers and be studied and sometimes even take to their unknown base.