<p>Well, I mean I guess the straight answer is that you need to know the physiology, pathology, and pharmacology of the skin. You have to be able to differentiate by tests and by physical exam a wide variety of diseases and conditions. While age and rejuvenatory medicine is a part of dermatology (and probably the main money maker of some derm practitioners) it is only a small part of the knowledge and abilities that you must gain to be a dermatologist. You will have to go through medical school and then train in derm for several years after that.</p>
<p>Here:</p>
<p>[Dermatology</a> - Wikipedia, the free encyclopedia](<a href=“http://en.wikipedia.org/wiki/Dermatology]Dermatology”>Dermatology - Wikipedia)</p>