I'm worried about a rash on my penis

Yesterday I noticed a dry patch of skin on the shaft of my penis near the base.  it's red and sensitive and is in slightly worse shape today than it was yesterday.  I'm trying to determine the cause of the rash since I haven't had sexual intercourse in a year and a half and I haven't done anything in the last few days that would cause this sort of irritation.  I have had oral sex with my girlfriend recently, but the part of my penis with the rash on it was never actually inside her mouth.  Is this possibly an STD or is it more likely a simple rash that happens to be on my penis instead of somewhere else on my body?  Another thing, I just came back to college and it is noticeably colder here.  It was about 7 degrees outside today with much colder wind.  Is there any possibility that the colder air dried out the skin on my penis and produced the rash?  Should I take any steps towards attempted treatment of the rash?  Or is it better to just leave it alone and try not to irritate it?

[Alan Rockoff, MD]

Sounds like eczema, more often than not a winter condition.  I'd apply hydrocortisone 1% twice a day.  If the patch goes right away, you can be confident that's what it is.  If it doesn't respond, show a doctor.  Doesn't sound like an STD, though.

Best.

Dr. Rockoff

[WastedBlues]

where can I buy 1% hydrocortisone ointment??  Is that something you can just pick up at Walmart?

[FredZ]

Yep, "equate" (house brand) hydrocortisone 1% cream

[Boota50]

HI. Just found the website it's great. My histoy... I got Herpes on my penis 4 years ago and have never had an outbreak to date...I think?  Recently I had sex with my girlfriend and within 15 minutes after I started getting a pile of little red blotches forming on the top of my shaft.  Days later it was just 3 or 4 blotched areas of redness, but not really above the surface.  By the end of the week it was peeling really bad,  It was like My penis shed all it's skin.  It seemed to have gone away , but 5 days after it cleared I had sex again, and within a 1/2 hour same thing.  Only now it's been well over a week and the conditions won't quite clear up.  I have no pain, it's just a little itch, nor is it drying out because I keep it moisturized, with Bactroban(it just happened to be lying around the house) PLeas  help . Thanks!