I'm interested to hear what other people add as well. A few things I put in on top of a basic pre built medical kit that only costs like $20. mutli vitamins, quick clot, Israeli bandage battle dressings (look these up if you don't know what they are, they are pretty awesome), deet bug repellent, patrollium jelly.
This is a good starting point as well.
Earlier versions to this one show the progression of thinning down kit size by using "multi-functional" (my term, can't remember his) items.
Wilderness Medicine, 5th Edition
2-Surgical mask w/ eye shield
4-Latex examination gloves (pr)
1-Dermatone sunscreen/chaffing cream
1-Tac-Pack Battle Pack Option 2
2-CELOX-A hemostat syringe
2-4.0 monofilament suture w/ curved needle
1-B-D Easy Scrub betadine brush
4-Foil packed single betadine swabs
2-Israeli battle dressing
8-Sterile 4x4 gauze pads
2-Coban 2" roll (tan)
60-Bactrim DS oral antibiotic and Rx
1-Bactroban (Mupirocin) ointment and Rx
6-Excedrin travel packets-extra strength
1-Moleskin 2 inch roll
10-Alcohol prep pads
10-Tincture of Benzoin ampulet
The above items fit in the lower/larger 7"x10" exterior pocket of a Maxpedition Falcon II pack.
Other multi-use items useful for medical, but not in that pocket are:
1-Multitool with scissors and plyers (needle driver)
1-Surgical tubing (add'l tournies)