Remember the corny old joke:
Old man marries attractive young woman. His friends are concerned because of his age. Aren’t you afraid vigorous sex could be fatal? they ask him. If she dies, she dies, he answered philosophically.
Actually, sex can be fatal. It’s a nice way to go, some may think. Maybe. I’ll let you know (joke, don’t write me)!
For reasons that will be obvious as you read, there is only one image for this newsletter! This is a stock photo not related to the cases below
But actually what is on my mind right now is a strange and unusual way sex could do you harm. It’s rare but – Hey! – this is my newsletter and I like sharing interesting stuff with you all. Besides, it’s another kind of “I told ‘em!” — you know, one of those things where I was writing about it decades ago.
What started this meditation off was a medical report in the British Journal of Medicine of a young woman who had sex with her husband, passed out and nearly died.1
In fact it was an allergic reaction and led to anaphylaxis, that very dangerous event of circulatory collapse that can be fatal. Fortunately she was a known allergic, in some danger, so she already had an emergency epinephrine pen (adrenalin to those of you in Europe) and gave herself a shot, which probably saved her life.
She was still in a state of semi-collapse when the ambulance arrived but the paramedics were able to stabilize her and get her to hospital, where she made a full recovery.
But allergy to what? That’s the strange part of the story: she had a known allergy to penicillin. But she had taken none. It was her husband’s medication. He had just started taking amoxycillin, they had intercourse, he ejaculated and there was enough penicillin in his semen to cause his wife to react badly!
This is something I’ve written about for decades, particularly reactions to food via semen. The husband eats a food; the wife is allergic to it; a bad reaction ensues. It’s one of the dark corners of food allergy; you know that food allergies was my wheelhouse for decades.
Indeed, I even reported a case where the wife was allergic to her husband’s actual semen. That could have been very tricky, of course. But fortunately I was using an allergy neutralization method at the time and was able to protect her sufficiently for her marriage to survive undisturbed.
Surprisingly, the top doctors have remained relatively unaware of this important risk factor and according to Cassim Akhoon, MB ChB, of King’s College Hospital in London, who was the lead author of the report in the BMJ, this effect is not something allergy specialists are mindful of, nor counselling people on when they’re being given a diagnosis of a drug allergy.
There is so little awareness of this phenomenon that the young woman patient expressed concern that the paramedics, nurse, and physician at the emergency department did not believe her when she told them she had not personally taken any penicillin, when she had a known allergy to it. “This was incredibly frustrating to have to explain multiple times and not feeling believed,” she said.
I personally never had the semen assayed for content in any of my cases (mostly food anyway, wouldn’t be practical). But there was an interesting case in 1989 in which a penicillin-sensitive woman suffered an immediate allergic reaction while her husband was receiving intravenous mezlocillin at home. The investigators demonstrated 42 micrograms of mezlocillin per millilitre of semen, providing direct evidence that his treatment had introduced the antibiotic into his seminal fluid.2
In 2019 a 31-year-old woman in Spain developed widespread hives, vomiting, breathlessness and wheezing following sexual activity involving vaginal intercourse and oral sex. She had a history of penicillin allergy but had taken no medication herself. Her partner was taking amoxicillin–clavulanic acid and ibuprofen for an ear infection; his last doses were approximately four hours before sex. She required adrenaline and other emergency treatment and recovered. The doctors suspected amoxicillin transferred in semen. However, the drug was not measured in semen, and she did not attend subsequent allergy testing, so this remains a suspected mechanism rather than a laboratory-confirmed one.
It’s important to bear in mind that an allergy to a drug carried in semen is different from allergy to seminal proteins themselves. The 2019 report discusses both, along with earlier reports involving penicillin, a heavy anti-psychotic medicine thioridazine and even a chemo agent transfer, vinblastine.3
My concern in all this is that what is actually happening will get missed in most cases. The majority of doctors have never been opened up to this possibility and, if you don’t think about it, you won’t find it!
I am supposing it would be quite rare when a patient is brought in collapsed that the medics would ask: “Have you had sex in the last few hours?”
Of course my clever readers will realize it is something that affects women primarily. But my curiosity was raised and I searched. I could only find one case of a man affected by drugs his wife was taking…
A 37-year-old man presented with a 7-day history of a lesion on his willy! His medical history was unremarkable, and he denied taking any medications in the last 8 months. His only sexual partner, his wife, was healthy apart from the occasional self-medication using diclofenac for pain.
Complete blood workup and routine urinalysis revealed no abnormalities. HIV antibodies, venereal disease, and immunoglobulins G and M against human herpes simplex viruses were all negative.
Drug intake history showed no recent medications, but he did report that his wife had just begun a course of diclofenac for her neck pains. His eruption occurred 2 days after sexual contact with his wife. Thus, a clinical diagnosis of a drug eruption after sexual contact with a partner on diclofenac was made.4
The same mechanism could conceivably affect a drug-allergic homosexual man exposed to his partner’s semen, although I could not locate a published case documenting this.
To your health,
Prof. Keith Scott-Mumby
The Alternative Doctor
References
- Akhoon C, et al “Systemic Anaphylaxis Following Intravaginal Exposure to Amoxicillin Transferred in Seminal Fluid” BMJ Case Reports; DOI: 10.1136/bcr-2025-271777
- Arch Intern Med. 1989 Jul;149(7):1603-4.
- “Anaphylaxis Probably Induced by Transfer of Amoxicillin via Oral Sex.” BMJ Case Reports. 2019;12(3):e227398
- Maatouk, I., Moutran, R., Fahed, M., & Helou, J. (2014). A “Sexually Transmitted” Fixed Drug Reaction. Sexually Transmitted Diseases, 41(10), 626–627. https://doi.org/10.1097/OLQ.0000000000000173
