With managed care less time for chit chat, it is even more unlikely that your dermatologist will take the time to get to the cause of your skin complaint, or refer you back to your internist or a specialist for more in-depth diagnostic measures. If you're lucky, he may spend a moment speculating, then give you a prescription to address the symptom -- temporarily...
In order to increase your chances of getting to the cause, tell him or her that you are not there to leave with a prescription, but to find out what may have caused the condition in the first place and what type of things you might avoid to shorten your recovery and prevent a reoccurrence. You may still choose to take the prescription, which only makes sense if you cannot tolerate the normal time it takes for most new conditions to clear themselves up (reunions, photo shoots, and TV appearances can definitely alter one's judgement about treatment approaches).
Which brings us to the next thing your dermatologist is unlikely to do for you but should: explain long-term, more serious side affects that may come from using the prescription he just wrote up. Some of the most commonly prescribed dermatological treatments have been associated with anything from "minor" complaints like allergies, yeast infections, bloated abdomen to birth defects, bone loss, and weakened immunity, which opens up an endless can of worms. From Accutane, to topical or internal steroids or antibiotics, the real internal side effects -- not just a brief description of the surface, short-term discomforts you may feel (which usually stand in for the more important information) -- are what need to be discussed. And if the consensus of the hundreds of women whose skin I work with every year is any measure, that almost never happens. You may have to find a dermatologist with both conventional and alternative treatments in their arsenal, in order to have your problem addressed holistically (see Dream Docs in the Living Beauty Section.)
It's just too easy to start a downward spiral with your beauty and vitality when you have to start dealing with the inevitable consequences of prescription side effects. If you ever figured out what caused your "mysterious" health decline and trace it back to when you began a certain "therapy" it'll make you kick yourself for not trying to clear it up naturally when you had the chance.
The upshot? Make your dermatologist listen to all of your complaints, familiarize him with the drugs you're taking already, and tell him what changes in your lifestyle and stress levels coincide with the onset of the condition. If he doesn't want to listen, find someone who does. Oh, and beware of your own impatient obsession with perfect skin. It could destroy your chances of ever having it again. For effective natural approaches to acne, psoriasis and dozens of other stubborn skin conditions, check out Michael T. Murray, MD's book, Natural Alternatives to Over-the-Counter and Prescription Drugs (William Morrow) and upcoming editions in InformedBeauty's Makeupless Makeover section.