Could you be allergic to seawater?

accreditation
iStock

Getting a rash after exposure to ocean water is quite common, according to the Amercian Academy of Allergy Asthma and Immunology (AAAAI).  However, a sea water or salt water allergy is unlikely say specialists.

Associate Professor Jonathan Peter, head of the Allergology and Clinical Immunology division at UCT’s Department of Medicine and the Allergy clinic at the UCT Lung institute, says that contact with seawater can be both good and bad for allergies.

Read: Seawater spray may cure colds

“Studies have shown benefits of saltwater (saline) nasal irrigation for allergic rhinitis sufferers,” Prof Peter says. There is however a small group of people who develop hives on contact with seawater or cold temperatures.

What is hives?

Hives or urticaria is a raised, itchy rash that appears on the skin, often accompanying allergic reactions. According to Prof Peter, specialists define a reaction to seawater as aquagenic (water) induced urticaria or cold-inducible urticaria. Studies demonstrate the salt content of water can also influence seawater’s ability to produce hives in certain patients.

Antihistamines can be used to prevent hives or to reduce symptoms in many cases. In a few extreme cases, patients must avoid water altogether to avoid developing anaphylaxis. Fortunately such severe cases are rare.

Read: Anaphylaxis

“In cold-induced urticaria, patients will normally have a threshold temperature below which they will develop hives, and some people have been force to relocate to warmer climates to treat their condition,” Prof Peter says.

'Something fishy'

“There are also a number of stinging fish in the sea that can cause skin and even toxic systemic reactions,” he adds.  A common example would be blue bottles found on the South African coastline.

Patients can also be allergic to shellfish or fish, in which case their bodies will make allergic antibodies (IgE) against certain shellfish or fish proteins. Symptoms of these allergies are usually triggered by ingestion, or in some cases, when someone directly handles shellfish during food preparation.  

Despite the fact that the ocean is filled with shellfish, seawater allergies and shellfish allergies are in no way connected, according to Prof Peter. Therefore patients who are allergic to shellfish don't have to worry about swimming.

Read More:

Allergy testing

So you think you have a food allergy?

New tactic to tackle peanut allergies

We live in a world where facts and fiction get blurred
In times of uncertainty you need journalism you can trust. For 14 free days, you can have access to a world of in-depth analyses, investigative journalism, top opinions and a range of features. Journalism strengthens democracy. Invest in the future today. Thereafter you will be billed R75 per month. You can cancel anytime and if you cancel within 14 days you won't be billed. 
Subscribe to News24
Voting Booth
Have you entered our Health of the Nation survey?
Please select an option Oops! Something went wrong, please try again later.
Results
Yes
27% - 9952 votes
No
73% - 26301 votes
Vote