Wthollow, that is not good, first of all Draxxin is NOT the cure all most farmers think it is. I have had this problem before and here is what works great for me. At first sight of swelling, if it is a mother raised fawn, using straight Xlazine (rompum) use a .5 cc dart with a .5 inch needle and tranq. with a blow gun. Cover his eyes. Guessing he is probably a 3-4 month old fawn now, I would administer 4cc Penicillin sub que - 2cc Nuflor .5 in muscle and 1.5 sub que - 1.25 Banimine IM (in muscle) - 1cc Vita B sub que. This has been a one time treatment for me and has worked very well. I used to use Baytril in place of the Nuflur and had to treat twice. Also, I would use peroxide in the mouth on the sore, then flush with water after bubbling stops. DO NOT ALLOW TO SWALLOW PEROXIDE. He also needs Probiotics. With all the Draxin and LA200 he has had you must give Probiotics (blue paste at farm store) squeeze in between cheek and gum. Reverse with 1cc of Tolazine and uncover his eyes. I use all 20 guage needles on these little guys but you will need an 18 guage needle for the Penicillin. If he is bottle fed I would use .4cc of Xlazine in a syringe to bring him down, reverse with 1cc Tolazine. Again, he needs the Probiotics, if possible give them for 3-5 days after.
Stevel, if it is allowed to pop open and drain on its own into the ground, the following year you may have it return as a bigger problem. The spores can multiply and return attacking more of your fawns than the year before. Absolutely no infectious puss is allowed to hit the ground. Catch it and kill it.
Also, do not cross contaminate by touching other equipment after handling infected animals. Jeff