Aquapac + SPIbelt works for me. Or any other truly waterproof phone holder bag in a waist pouch. I wouldn't necessarily leave it with a medical team because it can take a long time for them to get to you unless they are roaming and following you through the course.

So having worked at an org where we had two 5Ks per year, I am wondering about calling the race director at the org holding the event. If there is a medical team or coordinator who will be there on race day for the event, perhaps they can hold your labeled Epis. And I would have two--because you should and also in case one of yours were to get used on someone else (maybe they keep epi on hand though).

Or you could ask the race director of the staff at check in/site registration will be the same before and after the race and see if you could leave it there.

Or--you could put the epi container in a plastic ziplock bag and use ankle carrier or a spi belt. I wonder if there is an arm carrier.

Going to be participating in a obstacle course race shortly, but not sure what to do with the epi-pen.

I will not leAve it at home, but it is
Too hot to leave in car.
Can't wear it for fear of getting hurt wearing it during the race going in water, mud, p we and under obstacles
There is nobody coming to watch us who can hold it for us