Why don't doctors prescribe and use more alternative medicine ?

Training: Conventional medical training does not usually include extensive training in all modalities and healing systems encompassed by "alternative medicine." many of these, such as tcm, acupuncture, and homeopathy really do require years of study to do them well -- and some physicians do take this. Some also take fellowships to become at least familiar with these areas: www.Azcim.Org.

Evedence: It is not just training, but often lack of valid research proving that they work and are safe.