If you have a down (grey screen), and use a medkit on someone else you will gain no HP, but your down will be removed (no more grey screen).
This is also good to know for people who have the regen necklace trait. You can remove your down by healing someone else with a medkit, and keep all the green hp you’ve gotten from your trait. Use this to your team’s advantage.
Pass the word around, every group I played with last night did not know this. This knowledge might save a run in a pinch, pass it around please. Thanks for reading.