Poor Mr. A! He’s a 50-year-old married man, who, since the age of 19, has been plagued with a litany of unpleasant ailments every time he ejaculates.

On cue, after any orgasm, the beleaguered man would experience fever, weakness, exhaustion, loss of initiative, headache, disordered speech, irritability, forgetfulness and frightening dreams, not to mention swollen lips and throat.

The symptoms were so severe that he and his wife planned intercourse for Fridays so he’d have two days to recover before returning to work on Monday. He also suffered from premature ejaculation, so the problem was no picnic for Mrs. A, either. It’s a miracle they had two children.

We know all this because Mr. A’s condition is detailed in a just-published paper in the Journal of Sexual Medicine in which Dutch doctors describe what they call Post Orgasmic Illness Syndrome, or POIS.

POIS was first identified by the same team of doctors in 2002. Initially it was thought the cause might be psychological, possibly related to a syndrome called “dhat” that is sometimes reported among men in India and Sri Lanka that leaves them fearful of ejaculating.

Then, doctors in the United Kingdom noted similar symptoms in two men, including one whose problem improved dramatically by taking non-steroidal anti-inflammatory drugs just before and for two days after ejaculating. That seemed to indicate the problem was caused by some sort of immune system reaction.

The Dutch doctors figured POIS might lie in a man’s reaction to his own semen. They conducted skin prick testing, a common way to test for allergies, on 33 of the 45 men they’ve identified with potential POIS so far. When the men were exposed to their own semen this way, 29 of them had classic allergic reactions. Mr. A was one.

They tried treating him the way allergists sometimes treat food allergies, with “hyposensitization,” a technique that uses the allergen itself to treat the condition.

The doctors began a long series of treatments, first diluting the semen 40,000 times, inoculating him with it, and then, over a period of 31 months, gradually working up to a dilution of 1-to-20.

Amazingly, it worked. Mr. A eventually was able to ejaculate without debilitating illness. His symptoms did not disappear entirely, but they were much milder and lasted only a short time. Lead author Marcel Waldinger, of the Department of Psychiatry and Neurosexology at Haga Hospital in The Hague, said the results “contradict the idea that the complaints have a psychological cause.”

That’s good to know, but why, we may ask, is Mr. A allergic to his own semen at all? Women have been known to have allergic reactions to men’s emissions, but that’s entirely different.

Scientists aren’t sure, but they believe that a gap in the seminal plumbing somehow allows the semen to contact immune cells called T-lymphocytes which, in turn, sets off immune system alarm bells. With repeated exposure, the reaction becomes intense.

Whatever the cause, Mr. A is relieved that his problem has eased. Doctors report he is now “quite contented” at both home and work.

As a side benefit, the premature ejaculation stopped, too, so we can only surmise that Mrs. A is content as well.

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