Platelet Rich Plasma is a proven treatment for reversing hair loss and improving hair follicle health. The procedure involves re-injecting a portion of the patient's own blood into the scalp where hair loss is occurring. Unlike topical and oral medications, there are no known side effects and the procedure is considered very safe.
please see further information here; http://www.mensfitness.com/styleandgrooming/grooming/thinning-hair-modern-guide