Could my my severe allergic reaction after microneedling be caused by the collagen gel my therapist used? (Photos)

Thank you for your question. Please seek the advice and care of your physician. If you feel you had an allergic reaction to a medication or treatment, add this to your medical history to guide future medical or surgical therapies. Warm regards.

It sure looks and sounds like a reaction to the collagen gel--especially since you had no problems previously when hyaluronic acid gel was used.  The microneedling opens channels into the skin so anything applied on the skin after microneedling can "get in" much more easily.  The collagen gel may not cause issues on your intact skin but wreak havoc when placed on compromised skin.  If the prednisone was helpful that is another clue that your symptoms were caused by a stimulated immune system--and your immune system was probably stimulated by exposure to this gel.
The good news is there should be no long term problems or side effects from the reaction.
Hope this s helpful,
Dr. Amy