I remember hearing someone hypothesize that they were allergic to their partner's penis.

And then over the years since then I've heard more stories of irritation and swelling related to sex. It's made me wonder: is it possible for someone to be allergic to someone?

To having sex with them? [WHIP CRACKING, COUGH]. An allergy is quote “a damaging immune response by the body to a substance, especially pollen, fur, a particular food, or dust, to which it has become hypersensitive.” Essentially something environmental causes the immune system to respond abnormally with any number of these symptoms: a runny nose, sneezing, watery eyes, a rash, hives, ear problems, swelling, dizziness, trouble breathing, and/or digestive issues like throwing up and diarrhea. Do some people experience this with sex?

Yes. One possible explanation is an allergy to semen. There's a condition called post-orgasmic illness syndrome or post-ejaculatory syndrome where people feel tired, weak, feverish, and irritable, they have trouble concentrating and struggle with head congestion, promptly after ejaculating semen.

Researchers who've studied POIS aren't all in agreement, but many of them believe the cause is semen, those afflicted are allergic to their own semen. We do know it's possible to have an allergy to someone else's semen. It's called seminal plasma hypersensitivity.

Basically a protein in the fluid triggers an allergic reaction -- usually pain and burning. Seminalplasmaallergy.org also lists “hives, soft tissue swelling, chest tightness, shortness of breath, wheezing, diarrhea, dizziness, and loss of consciousness.” They have a screening questionnaire to determine if you're hypersensitive to seminal plasma. I want to stress the risk of not managing the problem.

Allergies to semen are usually progressive so the symptoms get worse the more the person is exposed to the allergen. On the upside, condoms and/or withdrawal can separate people from the fluid so they can have the pleasure of intercourse without the outbreak of hives. It is manageable.

On the downside, getting pregnant through sex or coming on a person's body are a lot trickier. Another sex-related allergen is latex. Latex is a milky substance collected from trees to make the natural rubber materials you see in condoms, gloves, and dams.

It's also used in some sex toys and clothing, so as you can imagine having an allergy to latex can be quite troublesome. Fortunately there are non-latex condoms: LifeStyles SKYN, Trojan Supra, Durex Avanti Bare,. Durex RealFeel, and Naturalamb.

There are also non-latex gloves and dams, and lots of non-latex suits and toys. So many options! So many workarounds for latex allergies.

But is it the latex you're allergic to? Latex isn't always the culprit in latex products. Some people have reactions to the casein -- a protein in milk used to make latex smooth, the dry-dusting powder that makes them less sticky, and the parabens which inhibit bacteria growth but also have questionable health effects.

As you probably know, there aren't regulations for sex products like there are for food. Packaging doesn't have to disclose what's in your condom. Some companies go ahead and tell us anyway though, emphasizing that they don't put these potential troublemakers in or on their products.

A lot of these involve the lubricants on the condoms, which you might not realize are in the lubes you use, too. Lubes that advertise flavors, cooling or heating sensations, and numbing can have any number of additives your system may not like:. Benzocaine and Lidocaine to reduce pain, and L-Arginine to boost arousal, nitrosamines, a preservative, and nonoxynol-9 to kill sperm.

Glycerin is another culprit - it can cause an allergic reaction like many of these, but also has the potential convert to sugar and instigate a yeast infection with similar symptoms to an allergy. Seeking the care of a medical provider, specifically an allergist, can help to determine whether the problem is because the substance is harmful or your body is sensitive. Online research can also provide a lot of insight as long as you make sure to get the information from credible sources.

This is how many people learn they have allergies to their birth control. They search the method they're using and the symptoms they're experiencing to find that they're allergic to:. Adhesive in the Ortho Evra patch, binding agent in pills, dyes in pills, liquid in the depo shot, nonoxynol-9 in spermicides, ethylene-vinyl acetate in the NuvaRing, and the barium sulphate in Nexplanon implants.

A good starting place for your own investigation is logging what happens. What are your symptoms and what happened that is the same or different than days without an allergic reaction? It may be that you're not allergic to sex but that the meal you ate before a sex date or the meds you take before bed (and sex) are messing with your immune system.

Maybe the pre-sex shower involves a soap that your body reacts to, or the massage oil you use to get in the mood actually irritates your skin. Truly being allergic to sex? To my knowledge there isn't a known allergy to intercourse -- but there's something very close called dyspareunia or genital armoring.

Basically something psychological precipitates a physiological response. For example abuse in the relationship, shame around sexuality, or the lack of trust in one's partner might correspond with inflammation or a rash. Like any other allergy, the immune system is doing its best to signal -- something is wrong!

The body may be spot on though, looking out for you, creating those puffy red welts to get your attention. Stay curious. I think bodies are incredibly powerful and intuitive.

I'm not a medical doctor or an allergist though, so if you suspect your system is responding to your environment in a damaging way, please seek professional care. My intention is to give people sexual health information so they can make informed decisions. If you'd like to support future episodes of Sexplanations, please go to patreon.com/sexplanations.