Program120 Male B Handbook on Preventive Medicine: A condensed version of the last half (on the benefit of hormones) of his famous Program 120 textbook on disease prevention, in this book Dr. Purser, a pituitary endocrinology researcher, lecturer and author, discusses normal lab values in men. He addresses proper testing, diagnoses, and hormone replacement therapy for hormones such as; somatropin, testosterone, thyroid, melatonin, and DHEA. Everything is highly referenced and researched. He also gives steps on how to make your levels normal and to make your life better!