I updated yesterday's post with a link to a great article on antibiotics. Thanks mucho, K!
Also, some useful supplies are available at much lower cost at your neighborhood ranch supply or feed store. I buy betadine solution and items for irrigating wounds in the horse supply area there.
Speaking of irrigating wounds: I forgot to mention that small separate baggies (or mini-tupperwares) of salt, baking soda and white sugar should be in your kit along with some small measuring spoons. I also keep a small canister of Morton's Salt Substitute (food grade potassium chloride or KCl) from the grocery store in my bag. USING A GOOD REFERENCE, you can do a lot with this stuff and clean water -- making a saline external irrigation or soaking solution; making a rehydration solution; adding a small amount (less than a dash) of KCl to some water to help relieve leg or foot cramps and many more. Other more serious conditions may be helped with these simple ingredients, but you must have a good emergency medical reference and some training or you can do real harm.