Mysterious rash

August 22, 2008 1:53 PM

Over the past ten days or so, I've developed a severe rash on my arms and legs. What could it be, and how can I treat it?

The rash appears in the form of smallish raised bumps (not always red, but often) clustered mostly around my elbows and kneecaps, but also spreading to the whole outside part of my limbs. The outsides of both arms are especially bad. The itching is not all that bad during the day, but by nighttime I'm scratching constantly. If I rub everything with cortisone cream, it gets a bit better, but only for a few hours. It has gotten noticeably worse since it started last week.

I have psoriasis, but the skin isn't noticeably hardening except on my elbows, and it's always been a fairly mild case. I have no other diseases that I know of. I moved into a new apartment on July 1st, so it could potentially be bedbugs (I live in NYC), but I haven't gotten new (used) furniture since early July. I have been under a lot of stress recently, because I'm essentially working 14 hours a day, but aside from a lack of energy I haven't noticed any other problems. There aren't any other recent lifestyle changes I can think of that could have caused this.

I'm going to the doctor on Monday, most likely. In the meantime, have you ever heard of something like this? I looked up the usual suspects--scabies and bedbugs--but I'm having trouble figuring out why it's only my arms and legs that are affected and nothing else.

I'm an early-20s, sedentary male, average build, shower twice a day.

posted by anonymous to health & fitness (12 comments total)

Sounds exactly like psoriasis vulgaris to me, and you say you have psoriasis. It's possible that your "fairly mild case" just got less mild, I guess. Stress + crappy immune system + maybe a virus or something = O HAI PSORIASIS.

It's only a couple days until you see your doctor but that really sounds pretty much like the classic start of a big attack of plaque psoriasis to me. The elbows and knees is a tell tale.
posted by Justinian at 2:01 PM on August 22, 2008

uh, I'm not a doctor so talk to yours.
posted by Justinian at 2:03 PM on August 22, 2008

Unfortunately I can't answer your question, but I had a similar thing happen to me, inexplicably, a couple weeks ago. I woke up with large raised itchy bumps on my elbows. Throughout the day it spread to my knees, then all over my limbs and around my eyes. The next day my doc put me on steroids and the whole thing cleared up within hours. Today I went to an allergist and we both have no idea what caused it. The allergist said sometimes the histamines in our cells just release randomly and can cause these unexplained hives. Of course your doctor will be able to give you a much more precise answer.

I hope that your doctor visit and maybe the help of some steroids can clear up your problem quickly and I'll be interested to see whether it was psoriasis or not. Feel better soon!
posted by wundermint at 2:26 PM on August 22, 2008

Especially since you are showering twice a day, be sure the shower soap you are using is not antibacterial. It is poorly documented, but some people have this kind of reaction to one of its ingredients, Triclosan.
posted by troybob at 2:50 PM on August 22, 2008

Troybob- thankyou- this has been driving mee mad for years, and yes, we use anti-bacterial washing powder.

Can I suggest to the OP to avoid scratching if possible- it's hard but it does reslly help to lessen the itching
posted by mattoxic at 6:17 PM on August 22, 2008

Heat rash? Does dusting with cornstarch stop the itching? Are you exacerbating it by rubbing with a towel when you dry off after your showers instead of patting dry?
posted by nonane at 6:20 PM on August 22, 2008

mattoxic: washing powder actually makes sense as the culprit in this case as well...the joints and outsides of the limbs are the primary points of clothes contact, so it could be just washing powder in general, not just antibacterial...
posted by troybob at 7:20 PM on August 22, 2008

Are you on any medication? Some medications can cause rashes. Your doctor should have told you this, but if you're on Lamictal, it can cause a life-threatening rash. Go to the ER if you're on Lamictal. I am not kidding; a relative almost died.
posted by desjardins at 8:46 AM on August 23, 2008

Showering 2x per day is excessive. Why shower so much if you are sedentary? Switch to something hemp-oil based like dr.bronner's baby soap instead of the laureth sulfate-laced conventional crap you can buy anywhere. Go to the dermatologist NOW.
posted by mamaraks at 8:52 AM on August 23, 2008

I understand people just want to help but... life threatening allergic reaction?

OP says he or she has psoriasis. The classic initial symptom of a big psoriasis vulgaris outbreak are reddish bumps on the knees and elbows which over time turn into the plaques the OP is expecting. The OP says he or she is under a lot of stress right now. Stress is known to contribute to psoriasis outbreaks.

Hoofbeats, horses, zebras, and all that. No reason to scare the OP.
posted by Justinian at 10:46 AM on August 23, 2008

There's no harm in throwing out a few things that the OP might not be aware of. They are easy enough to rule out by the OP, so it's not like taking the time to read them is delaying his ambulance trip to the hospital or anything. The answers here so far almost all are based on personal experience, and none seem to be a joke.

And really, are people going so far as actively campaigning for 'best answer' these days ?
posted by troybob at 3:32 PM on August 23, 2008

I'm not campaigning for anything; I don't care if anything gets marked best answer. But I was under the impression if we thought some answers were inaccurate, it was appropriate to say so. Is it really a problem saying that I think arguing for worst case scenarios without any real basis is not that helpful?

Without more info from the OP there really isn't any reason to suspect any of the worst case scenarios when a simple, logical, and obvious answer presents itself. And he/she is going to the doctor in two days anyway. That's not lobbying, it's answering the question as best I can.
posted by Justinian at 4:07 PM on August 23, 2008