What It's Like to Be Allergic to Cum

Minutes after coming into contact with a partner’s cum, some people feel a burning-itching sensation and notice redness and swelling wherever it lands. Many fear their reaction is the first sign of some nebulous infection—these are among the best-known signs of STIs, after all. But these may actually be symptoms of a condition called seminal plasma hypersensitivity, colloquially known as a semen allergy. 

Recent analyses suggest at least 40,000 women in the U.S. experience seminal plasma hypersensitivity—but since doctors first identified the issue 60 years ago, they’ve only published a handful of detailed (and mostly extreme) case studies. There are no confirmed cases of men who are allergic to cum, though a few researchers believe that guys can develop allergies to their own semen and exhibit completely different symptoms. 

No one’s sure which of the dozens of elements that make up semen are to blame, though this hypersensitivity definitely isn’t triggered by sperm. Nor do we know why some people are consistently sensitive, while others’ symptoms fluctuate over time, or even from partner to partner. Experts speculate that these variations could be the result of hormonal shifts or the effects of varied diets and lifestyles on semen, but they don’t have enough evidence to be sure. 

What we do know is that semen allergies can have huge effects on people’s sex lives. People often report changing their habits to avoid direct exposure to irritating semen—even pre-cum. They use condoms when they’d prefer not to, and facials and oral sex are off the table. (Although the condition itself doesn’t interfere with fertility, some efforts to avoid its effects can make getting pregnant tricky.) Some folks’ symptoms are so severe—body-wide hives, dizziness, gastric distress, or even anaphylaxis—that they can create anxieties that lead them to avoid or be less excited about sex. 

The few doctors who specialize in this condition treat it through established allergy mitigation practices. But embarrassment stops many people from seeking treatment. Because specialists are few and far between, those who do look for help are often dismissed or misdiagnosed by care providers. Even those who reach an expert find that certain treatments don’t work for everyone. The lack of access to care, stigma around, and difficulty of treating semen allergies mean that seminal plasma hypersensitivity is often a lifelong condition that people have to endure without meaningful guidance.

To find how people can manage sex alongside a semen allergy, VICE spoke to Lucy, who was diagnosed with the condition over a decade ago. She told us about what she and her long-term partner have experienced, her attempts to treat it, and how they’ve responded to the challenges it has created in their sex life.  

VICE has changed Lucy’s name to protect her privacy. This interview has been edited for length and clarity

VICE: When did you first realize that you had allergic reactions to semen? 

Lucy: I was in my early 20s. I was having sex with a guy and the condom broke. When he ejaculated in me, that was the first time I’d come into direct contact with semen in my life. Instantly, I felt a lot of burning and redness. I don’t remember if there was swelling. But it felt like my vulva was on fire, and I just wanted to get the semen out of me. [Laughs] It didn’t help that I was freaked out about the broken condom.

It was a strange and stressful experience. But I have a bit of a medical background, and I knew a lot about sexual health, so I didn’t think it was something like an STI. Instead, I thought, Wow, this is crazy—it’s almost like I’m having an allergic reaction.

How long did it take you to figure out that this was, in fact, an allergy?

It took a while. I mainly identified as someone who wanted to be with non-male partners, so after that I told myself I wouldn’t have to worry about this for a while and put it on the back burner because I didn’t see myself having sex—at least, unprotected sex—with men again anytime soon after that. 

About a year later, I started dating the man who’s now my husband. Eventually, we wanted to stop using condoms. I said, “Well, I’m nervous about taking that step because I once had this reaction to semen, and I’m scared that I could have either the same type of response, which was extremely uncomfortable, or something even worse.” He was very thoughtful and responsive. We eventually decided that the pull-out method was worth the risk. But you’re still exposed to pre-cum like that, so sex burned a little whenever we didn’t use a condom. (Also, it’s not a good birth control method, but I was on a different form of birth control by then.) There were concerns about whether he’d lose control when he pulled out and get semen on my skin too, but we never actually had an issue with that. 

Still, I was concerned that eventually, my reactions might get worse—that I might have an anaphylactic reaction. That’s a big part of why we never did, and still don’t do, much oral sex. I was pretty freaked out that sex could kill me. Actually, I was freaked out enough to think, Well, maybe I really should just stick with female partners. [Laughs] 

How did this persistent issue factor into your thoughts about your sexuality? 

I’m a pretty pragmatic person. I don’t believe things happen for a reason, or to tell you something. Still, I did sometimes feel like it’d just simplify my life a lot if I stopped dating men. [Laughs] But at this point in our relationship, I was in love. I thought we might be together for a long time. Actually, I’m pretty thankful for my first exposure to semen, because that helped me know from the start that I wasn’t just allergic to my current partner. I’m allergic to semen in general!

I decided to look for an allergist. We didn’t live near a big city, so there were slim pickings. I just called around. I was uncomfortable talking about this, as you can imagine, but I’d ask, “Does the doctor here have any experience with semen allergies? Because I think I might have one, and I want to figure out what I can do about it.” 

One person said, “Yeah, the doctor does. You can come here. Bring a sample of your partner’s semen with you.” I scheduled an appointment for right after work one day. But our schedules meant that I then had to bring my partner’s semen to work—leaving it in the staff fridge near my lunch.

They were nice about it on the phone, but I was still anxious about whether this doctor would take me seriously—and about what it’d mean if I actually did have a semen allergy. They did a scratch test on my arm, pricking me once with histamine, once with saline, and once with my partner’s semen. I thought, OK, I’m just crazy. This isn’t going to turn out positive. But after 15 or 30 minutes, my arm was swelling up both where they’d pricked me with histamine and with semen. 

I tried to convince myself I was just turning red because I’m pale and they’d scratched me. But the nurse looked at my arm and said, “That’s positive.” 

I said, “Well, shit.” 

What did you do once you learned that, yes, you really are allergic to semen? 

The doctor came in and revealed that, no, she didn’t actually have any prior experience with this. I told her I’d found a guy who had developed protocols for treating this. The doctor said she was comfortable giving it a shot. We set an appointment to do an intravaginal graded challenge. She just said, “Yeah, bring a lot of cum to the appointment, and we’ll take care of it.” [Laughs] 

My partner was down to try this because he wanted to be able to have sex without a condom and not worry about killing me in the process. So we both went in for the procedure. I got into stirrups—at an allergist’s office. Which, I didn’t even realize allergists would have stirrups. It was super weird! [Laughs.] But I’m a pretty open person, especially in medical situations, so I just rolled with it. I had to be there for half a day. They administered diluted semen every 30 minutes in the weirdest way: using a cannula to push it up, against gravity, into my vagina. It wasn’t even all getting in. But I had no prior experience, so I figured, Well, all right. We finished, and the doctor said, “You might be cured. We don’t know. The real test is for you to have sex without a condom within 24 or 48 hours, and let us know how it goes.” 

How did it go? 

We didn’t feel very sexy after all of this, especially given all the weight we placed on whether it’d work. So we put it off, then had sex right before the end of the window—and right before a nice dinner to treat ourselves for going through this. We were nervous. Right after he came, I didn’t feel anything. I was so happy I cried. But within an hour, I started to get a headache, which is unusual for me. We made sure we had an EpiPen, and I took an antihistamine, told myself I’d be OK, and got in the car to go to dinner. Then I started feeling worse. My breathing was labored. I wasn’t sure whether I was having a panic attack, or what. 

Eventually, I said, “We have to go to the hospital.” On our way, I started having trouble speaking and felt my throat closing up, but I managed to say, “I need you to pull over and put the EpiPen in my thigh.” He did it, and I felt better immediately, but I still needed to go to the emergency department to get checked out. I walked into our small-town hospital and the nurse—this really hot woman I think I recognized from college and who was clearly a lesbian [laughs]—asked me what was wrong. I said, “I think I’m having an allergic reaction.” 

She said, “What are you allergic to?”

I started crying and just screamed, in a really high-pitched voice, “Semen!”   

After that, my partner and I decided we weren’t going to fuck around with him getting his semen anywhere near me anymore. We’d use condoms or whatever we needed to do. Unless we decided that we wanted to have children. Then I’d get desensitized by the leading expert on this. 

Which you eventually did?

Yeah. Fast forward five years: We went to the doctor who developed the treatment protocol I’d tried, and I did another intravaginal graded challenge—even though I was very skeptical by then. He didn’t use a cannula. [Laughs] And it worked! I was fully desensitized and no longer had any reactions when I came into contact with my partner’s semen. But that wasn’t the end of it. 

The doctor said I’d need to be exposed to my partner’s semen around twice a week. You know, it’s just like how some people need regular allergy shots. Well … I need a cumshot. [Laughs]

We’d been together for years, were going into our 30s, and both traveled a lot for work, so we were like, “How are we going to do that?” This doctor was an older guy who thinks people always love having sex, so he was like, “Oh, come on, usually guys love it when I prescribe this!” 

I had other questions, like, “Would anal exposure work? Would oral exposure count? Is anything other than vaginal exposure going to keep me desensitized?” This doctor didn’t know how to answer those questions—he just said there was no evidence to suggest other exposures would help. Knowing that the vaginal mucosa is different from other tissue, I didn’t want to try relying on any other part of my body if we didn’t know it’d work, so we went with that. 

How did you deal with the medical need to have sex so often, when that wasn’t something either of you were hyped about?

Well, we stretched the window as far as we felt we could, knowing that we still had an EpiPen just in case. Every five days, I get semen exposure either through sex or otherwise—and frankly, often, we don’t do it through sex. My partner cums in a designated cup that we don’t give to guests. [Laughs] Then I use an oral medication syringe and insert it into my vagina. 

It’s unpleasant for us. It’s hard for my partner to cum reliably every fifth day when he’s on medications that might affect his libido. There’s such pressure to keep that up, and he knows there’s always a chance that the next time we have sex my throat could close up and I could die. I mean, that’s fucked up! We’ve had therapy sessions where we’ve talked through this, but it’s still something we struggle with. But it’s been almost seven years, and we’ve gotten used to it.

Do you think this medicalization of your sex life has had a long-term effect on your sex drive, or the way you relate to sex more generally? 

For sure. But I have other chronic health issues that affect our sex life. We’re getting older; we’re not in our 20s anymore. And we have a young child, so we’re constantly exhausted. It’s not all about the semen allergy. There are a lot of things that have put limits on our sex life. 

How do you deal with that? 

We’re pretty resilient. We’re a good pair. But we do look forward to the point when we’re no longer planning to have kids, so we can stop this. (We plan to have one more.) We’re also both still hoping there’ll be more research. That someone will find another way to deal with this.