Oh good, something else we can blame on estrogen: severe allergic reactions.

The Washington Post says female allergy sufferers tend to go into anaphylaxis more often than men, and a new study from the National Institutes of of Allergy and Infectious Diseases suggests a possible contributing factor:

Researchers found that female mice experience more severe and longer-lasting anaphylactic reactions than males. They found that estrogen enhances the levels and activity of an enzyme lining the blood vessels, which in turn causes some of the severe allergic reactions. The enzyme increases the production of a substance called nitric oxide, which creates a drop in blood pressure and allows fluid in blood vessels to leak into the tissues, resulting in swelling.

When the researchers blocked that enzyme's activity, the difference between the male and female mice disappeared.

Science Daily specifies it's estradiol specifically (a type of estrogen) that's at work, here.

Obviously that doesn't mean there's a decisive link in humans, so there's no way to apply the research to treatment just yet, without further research. But study author Dean Metcalfe said doctors should be paying attention if, for instance, a woman with already severe allergies seems to have worse reactions while on birth control or taking the supplement L-arginine. He also called for called for more investigation into the influence of sex differences on disease, generally.


Image via AP