The sensation I'm talking about is subtle. It's the fleeting despair that occasionally accompanies even the least noteworthy climax. Not everyone experiences it, but if you have you'll know exactly what I mean.
Called post-coital tristesse (PCT) by people aware of that term, the melancholy one can feel after an orgasm is actually a very well documented phenomenon, with references dating back to the Roman Empire. Sometime around 150 AD, in fact, the prominent Greek physician Galen wrote, "Every animal is sad after coitus except the human female and the rooster."
Mind you, as prominent as he was, Galen didn't have it all figured out; both sexes are affected and the experience can differ radically from person to person. It's also not to be confused with post-orgasmic illness syndrome (POIS), a rare condition that could be due to anything from a lack of progesterone to a semen allergy. The syndrome can cause sufferers to experience a wide range of symptoms, including apathy, itchy eyes and weepiness, for up to several days after an orgasm.
My personal experience of post-coital blues has been nothing more than the occasional feeling of despondence for a couple of seconds, before moving on and making a pizza, or whatever. But when I asked around online, some who replied complained of intense feelings of gloom that lasted for hours.
"I get post-coital sadness a minority of the time after I orgasm," said one female sufferer. "Maybe 15 to 20 percent of the time after I have sex, and no more than 5 percent of the time after I masturbate. I tend toward feelings of depression at times already, and sometimes bouts of post-coital blues lead to hours of sadness or despair."
But, she added, "The feelings are easily assuaged by extra cuddle time and lovey-dovey shit."
So what's to blame? Evolution? Neurochemistry? An innate sense of misery, peeping out to kick us in the brain while we're supposed to be feeling all elated and satisfied?
I wanted to know how human beings relate to sex existentially. After all, it's such a fundamental part of life – if it wasn't for sex, none of us would have been born. According to London-based psychiatrist Anthony Stone, the momentary despair may – for men, at least – have something to do with a perceived loss of purpose.
"When clients come to me and want to talk about sex, I immediately think, 'Power'," he said. "Men are often at their most 'powerful' when being sexual. Just think about young men and [their] seduction routines – displaying their feathers like peacocks. Post-sex, men can feel powerless, a spent force; they've lost the ability to impregnate. In some cases, this can feel like depression or a desire to die – sometimes like 'maleness' has been lost."
Aristotle, Nietzsche and the Dutch philosopher Baruch Spinoza all accepted the phenomenon as having to do, in part, with the expenditure of the "life force". Problem is, it's not only men who suffer from post-coital sadness.
Freud wrote in depth on the overwhelming nature of the human sex drive. He claimed one of the fundamental reasons we crave sex so voraciously was for more than the fulfilment of a biological need. Rather, he believed it was the closest someone could come to escaping the intrinsic isolation of human existence – by literally being inside another person (and vice versa).
So when sex is over, you can't help but realise that – as "together" as all the fondling, kissing and mutual involuntary leg cramps might have made you feel – you're really always alone.
"We are talking about loss," said Anthony. "Much of life is made up of living and dying; saying hello and goodbye; being born and bereaving. How we manage these transitions is essential to our wellbeing."
And the same theory applies to sex. "Do you feel sad at the end of an amazing film, wishing it could have gone on forever? Nothing lasts forever – we are always in the presence of our demise," he added, ominously.
In 2009, American psychiatrist Dr Richard Friedman investigated possible biological explanations for post-coital sadness. He wanted to prove that the phenomenon was, in some cases, the result of a rebound in the amygdala – the part of the brain that deals with fear and anxiety. During sex, the amygdala "dampens" fear and anxiety. Thus, post-coital sadness could be explained as amygdala function sharply returning to normal levels.
Taking that into account, those temporary feelings of depression could be compared to what you feel like the day after deciding to drop another pill as the birds started singing, only on a smaller scale. What goes up must come down.
"Sigmund Freud 1926", by Ferdinand Schmutzer (Photo via)
To test his hypothesis, Dr Friedman conducted a somewhat unorthodox experiment. A number of test subjects were given selective serotonin reuptake inhibitors (SSRIs), drugs used to treat depression. The anti-depressive qualities don't kick in until the medication has been taken for a substantial amount of time, but the physical side effects begin almost instantly. One of these side effects is a decrease in sexual pleasure, and as Dr Friedman predicted, this minor loss of enjoyment correlated with a marginal drop in reported feelings of sadness after sex.
To me, this seemed to carry a pretty depressing implication: if you want to stop getting post-coital sadness, you need to have worse sex. That clearly isn't an attractive, or particularly pragmatic, option (for obvious reasons). But luckily, in the majority of cases, post-coital negative feelings aren't intense or long-lasting enough to warrant medical attention.
So as is the case with all psychological ailments, the best course of action is to visit a psychiatrist or psychotherapist if the feelings do become overwhelming.
For an opinion on how the problem would be treated if it got to that level, I spoke to Dr Dušan Potkonjak, associate specialist in psychiatry at Goodmayes Hospital, London. "Human reaction is not segmental," he told me. "I would explore the whole history of [a patient's] sexual encounters and their pattern of human relationships. Our potential for intimacy can be badly affected if our first experiences were humiliating or we experienced rejection – it's like Pavlovian conditioning."
However, this doesn't necessarily mean that those who experience post-coital sadness have had a rocky relationship history. "Every human being is totally different and accumulates experiences and attachments differently," added Dr Potkonjak. "In any encounter we have all kinds of immediate responses to people – conscious and unconscious. We always make links with our memories, and it can complicate the here and now."
Ultimately, then, the causes of post-coital sadness are elusive and invariably subjective. It can be a chemical problem for some and an existential one for others. Or it could simply be down to an unfortunate romantic incident in your past.
So if you do find yourself in an brief emotional black hole after an orgasm, don't fret. Picture it this way: you're just part of quite a large club – featuring esteemed alumni such as Spinoza and Freud – who feel a little bit shit after sex.
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