I have been a diabetic for over 30 years now, since I was 7 and a reenactor since i was 14. I have had various ways to deal with the multitude of complications of being a diabetic and pretending to be either a CW soldier or WWII GI or Kraut, or WWI Doughboy.
These have ranged from ( and I am not kidding here.) having my Mom come give me my shot in the morning at a near by reenactment

to being positively sick because I let my blood sugars go to hell for 2 days.

Now I am on an insulin pump and I tell ya what it has made doing this crazy stuff so much easier and still keep control of my blood sugars. These thing are darn near indestructible and easy to carry in you pocket. Just have to make sure you load it up before you go to the event and of course stash your gluclometer somewhere in your kit. I have always been sensitive to ruining others "moments" and try to be discrete as possible.
I could tell you all kinds of stories of low blood sugar episodes and reenacting. ( At my first GW event my trench mate had to explain to 2 Huns that i was "stalking" that my blood sugar was low...I was doing an Elmer Fudd imitation. My apologies to those guys.

) I have been dragged off the field by EMT's thinking I was having heat stroke when all I needed was some pick me up sugar..that was at the 135th of Chickamauga, I had to walk back from the aid station with no shoes, they had stripped them and dragged me off before I or my pards could explain that it all was under control!)
Anyways the Insulin pump has changed much of that, now even if I only eat a bit I can immediately control the amount of insulin and I can adjust it to take in consideration the increased physical activity.
I would like to hear form other reenactors and what they have done to deal with their medical issues and how they accommodate them.
Maybe we can all compare notes and help each other with ways to make it easier, be it Asthma diabetes, you name it.
Lee