I had a recurring problem witha wc deremensis a few years back. Swollen lips. I believe it was, in fact, Carlton who suggested avitamin C problem. This guy had recurring oral abscesses along with the swelling. I had kept his vitamins limited to just d3, for fear of giving too much. I upped the supplementation with herptivite, and within a few weeks, the problem was gone.
In fact, if you look in my photos, one of my p pics shows this. The little guy that los like he was smiling at the camera - the swelling was there on the pc. It was minor, either going away or just about to get worse - I can't remember!