Hives while swimming

[MSilvia]

A friend of mine went swimming off one of the beaches in Gloucester, MA, just south of Good Harbor beach, and he and his girlfriend came out of the water just fine. After a second swim he, but not she, had hives (small welts) covering his entire body except his head, which had been underwater. He has no known allergies. Any thoughts what might have caused them?

 

[Laurence Stein DDS]

MSilvia,

Was your friend wearing sunscreen? While he reports no allergies, it is still possible to develope an allergy.

Many sunscreens contain PABA...para amino benzoic acid. It is a potential allergen. Try the following link or do a search including sunscreen and allergy

http://www.dermnetnz.org/index.html

If you were swimming with him, I would be less suspicious of some stinging organism--you should have been affected too.

Hope he feels better.

Regards,

Larry Stein

 

[DocVikingo]

Hi MSilvia,

I know several divers who dive that area several times a week, and asked them about your situation. They indicated that they were not aware of anything in the water or air at this time that might account for your friend's complaint.

The fact that he was swimming with his girlfriend and she was entirely unaffected, and that his head was unaffected, rather argues against anything in the water.

Best regards.

DocVikingo

 

[John Reinertson]

Hives are a tough problem.
In patients with recurrent hives, a cause can be identified perhaps 50% of the time.
When it is a one-time thing it's tougher yet.

One thing that should be checked for and ruled out is an illness called cold-induced urticaria, or hives triggered by cold.
Since water conducts heat better than air, and some cases of hives progress to shock or breathing difficulties, this is a contraindication to diving, and indded can contraindicate swimming.

If your friend has had no other rashes, and can be in cold water without rashes, itching, or difficulty breathing, this is probably not the case, but would be worth discussing.

As one who has a personal mild allergy to PABA, I can tell you Doc Stein's comments are very accurate. Most people with PABA allergy will be most sensitive where the skin is thinnest.

As I said above, these are not easy questions to answer, and you may never get a complete answer.

Good luck on your search.
John

 

[Laurence Stein DDS]

John,

I was thinking today about my reply and also remembered cold induced hives. You discribed it well.

I once put my little toe into the water off Cape Cod and swore "never again"! I'm sticking to sunny South Florida.

Good pick.

Larry Stein

 

[MSilvia]

Brian (my friend) never wears sunscreen, and is a white water rafting guide in Maine and New Hampshire... he's quite accustomed to being in cold water. That aside, the water temp in Gloucester was around 65 that day... hardly what anyone around here would consider cold.

Puzzling...