I have dry, itchy and rough skin on and under the rim of my penis. What could this be and how can I treat it?

Dermatologist. This is an unusual place to develop dry,rough, and itchy skin. If you use condoms you could have a skin reaction to them. Also if you have intercourse with a partner who uses spermicide cream, it's a possible cause. It doesn't appear to be a sexually transmitted disease, but a dermatologist would be helpful in evaluating and advising you.