[Itse]

Reminds me of this:

http://www.dailymail.co.uk/health/ar...-recorded.html

It is the first recorded case of an allergic reaction to Brazil nuts through intercourse.

...

It appears that Brazil nut proteins resist digestion, which is why they generally end up in the immune system, triggering immune reactions. They discovered the woman's skin swelled up and his semen caused a reaction just three to four hours after eating the nuts.

But because the couple split up after the reaction, scientists were not able to carry out further tests.