You know that the sun increases the risk of skin cancer for most people. You probably don’t know that for some people, the sun is the source of a terrible itchy rash — they’re allergic to the sun.
The radiation from the sun triggers some response in everyone’s skin. In some, the radiation triggers an immune reaction, leading to red, itchy, burning bumps. There are several diseases that are caused by sun which lead to rashes. Here are a few:
Polymorphous Light Eruption (PMLE): This is the most common. It is usually characterized by tiny, itchy red bumps that develop on the arms, neck and face hours after sun exposure. It is often seen in the spring and occurs more frequently in young people.
Actinic Prurigo: This is seen as itchy red bumps that occur mostly in children who are sensitive to the sun. Like PMLE, it occurs mostly on the face (including lips), arms, and hands. It can be more severe than PMLE and can lead to scarring in rare instances.
Chronic Actinic Dermatitis: This usually affects adults. It starts in areas exposed to the sun, but can spread to other areas. It is often terribly itchy and can be triggered by sunlight even though car windows.
Solar hives (urticaria): These are itchy pink whelts that develop within minutes of sun exposure. The rash develops quickly and fades quickly but can be intensely itchy. Antihistamines such as Zyrtec (ceterizine) or Benedryl (diphenhydramine) can help.
There are other sun-induced diseases, including ones triggered by medications. I’ll write about them in a future post. In all of these conditions, the most important thing to remember is to avoid sun exposure as much as possible. If you develop an itchy or burning rash after sun exposure, then see your physician for an exam and for advice.
I was at a coffee bar in Redwood City yesterday, minding my own business when I found a tube of medication. Someone had accidently left a tube of topical Botox at the bar. Was this a plant? Is this the real prototype or just a fake? What should DermodoDoc do? I just had to blog on it.
Botulinum toxin is the most common cosmetic treatment with millions of patients injected every year. Brand names like Botox and Dysport are injectable drugs that cause temporary paralysis of the muscles in your face smoothing wrinkles, sometimes dramatically.
Injected botulinum toxin is also a good treatment for excess sweating in your underarms or on your hands, which is called hyperhidrosis. The toxin blocks the signals that turn on sweating thereby preventing you from sweating.
Up to now, the only way to use Botox has been to inject it. That may change. There is a topical botulinum toxin gel being developed. If the toxin could penetrate the skin, then it could work without having to be injected, which is a good thing since there are people out there who really don’t like needles. Topical botulinum toxin would likely be most effective in places where the skin is thin, such as the underarms. Getting enough medication to penetrate your forehead might be difficult. How effective it will be for treating wrinkles is yet to be seen.
We will have to wait to see when the product is finally released. Until then, I’m waiting for Steve Jobs to call me personally to ask for his Botox back. It must be his, right?