You can prefill the needle and keep it in a pencil case. Syringes work fine through clothes, although not ideal.
I'm an insulin dependent (T1) diabetic. I keep a glucagon kit on hand in case of an emergency. It's a syringe and vial that needs to be mixed. The idea is that if you're unconscious, someone that is close can administer. If I were severely hypoglycemic I'd have problems, but my partner wouldn't. I could pull it off if it were prefilled, but you can't prefill glucagon.
Edit: I totally get it and agree though. Life saving medicine shouldn't have any barriers.