This is what I have in my first-aid kit: Marijuana. Doctors didnt want marijuana made illegal, because it has so many medicinal uses. It is a pain-killer, a muscle relaxer (it was used for women giving birth), helps with insomnia, and increases appetite. Thats a lot of uses for one herb.
Tea Tree Oil. Its an antiseptic and promotes healing. One of my friends stepped on a nail. The doctor told him it wouldnt heal and it wanted to ream it out. My friend declined. I had him put tea tree oil on it and it started to heal. The doctor told him, I dont know what you are doing, but keep doing it. It healed completely with no scarring. Ive seen people use it for toenail fungus and for gum disease.
Black Pepper. Believe it or not, but if you put black pepper on a cut it will stop bleeding.
Lavender Oil. Lavender oil is good for minor burns and promotes healing. It makes you smell good, too.
Clove oil. I once cracked a molar that had a large filling in it. Since it was in the evening, I couldnt get to the dentist. I rubbed clove oil on the gum and the pain went away. Unfortunately, it only last half-an-hour before I had to reapply it, but it was bliss for that 30 minutes.
Peppermint/Ginger tea. This is a good one for digestive problems and an upset stomach.
Acupuncture pressure points. The main one, and its pretty much the only one I use, is located in the web between your thumb and first finger. You have to dig to find it, and when you do, it will hurt when you knead it. Its pretty much a pain-killer. The first time I used it on a woman her headache and her cramps went away in about a minute.
I have found the above covers about 90% of medical problems that most people suffer from, that dont require an ER visit which these days costs about $500..