On a serious note, I've heard, if you've taken a Wilderness First Aid Course, or Mountain Oriented First Aid Course, a physician will prescribe you some narcotic medication.
This is for the sake of controlling pain until you can make it out of the backcountry.
YMMV, of course.
1) Epinepherine auto injector-for severe allergic reations.
2) Antibiotics for upper respiratory illnesses, urinary tract infections and ear/eye infections--know which is for what and the dose and duration.
3) Albuterol/Atrovent-for asthmatics
4) Lasix-a potent diuretic--for pulmonary edema
5) Phenergan--for nausea/vomiting
6) Glucagen--for hypoglycemic emergencies and no IV access is available.
If you have high blood pressure, heart conditions, diabetes, other respiratory disease, psychiatric meds, take hormone replacements or medications for other chronic conditions, ask your doctor for a prescription covering three months of your meds.
DO NOT. I repeat DO NOT ask for pain medication or any schedule 1-4 drugs. This includes pains meds, xanax, valium or any barbituate.
If you can get to Mexico (like border towns), you can buy most of it over the counter at their pharmacies. Amoxicillian is a great all around antibiotic for upper respiratory infections (unless you are allergic to penicillian) and Ciprofloxin is good for UTIs. You can buy the amoxicillan in Mexico for about $15 for a 1000 500 mg capsules.
Be sure that you know what you are buying, the appropriate med, dose and duration as well as drug interactions, indications, contrindications and if it is appropriate you you if you are allergic. Keflex for example has a 12% penicillin in it--very dangerous if you are allergic to PCN.