For many, the thought of sex the day after a heavy drinking session is repulsive. Your breath is hot, your head is thumping and you stink.
But for a significant chunk of us – mostly men – their libido goes through the roof when they are hungover.
‘Why do I get SO horny when I’m hungover?’ reads one Reddit post, ‘There must be a science to it. I always feel like a wild animal after a night out drinking.’
Another reads: ‘Why am I so horny when I’m hungover, regardless of how much sex I had the night before? Anyone else experience this and know why?’
There are hundreds of similar posts on online forums, and the ‘hangover horn phenomenon’ has confused doctors because of how unexpected it is.
Dr Sanam Hafeez, a New York City-based neuropsychologist, told DailyMail.com having sex when hungover ‘might sound counterintuitive,’ but the effects of alcohol from the night before trickle into the next day, making you feel more sexually adventurous.
Having sex releases hormones that help reduce pain and improve mood – which can be useful when suffering from a hangover that results in head and body aches and anxiety
It’s a widely accepted fact that being drunk makes people frisky, as it loosens them up and lowers their inhibitions, and it temporarily increases dopamine – known as the happy hormone – levels in the brain.
And Dr Hafeez said those physiological changes feed the hangover sex drive surge.
She said: ‘Chronic alcohol consumption disrupts the balance of neurotransmitters in the brain, including dopamine, serotonin, and endorphins.
‘As the body attempts to restore these levels to normal during withdrawal, fluctuations in mood and arousal can occur, potentially leading to heightened sexual desire.’
About 12 hours after you stop drinking, and a hangover begins to set in, levels of dopamine begin to drop.
While depressed dopamine levels can lead to lower libido and sexual dysfunction, people who are hungover search for sex in an effort to increase this hormone level and make themselves feel better.
Sex triggers the release of dopamine, along with other mood-boosting chemicals like endorphins and oxytocin.
Endorphins are chemicals in the brain activated by sex that have natural opiate-like properties.
They help reduce pain and improve mood – which can be useful when suffering from a hangover that results in head and body aches and anxiety.
Studies have also shown pain can be significantly alleviated by having sex or experiencing an orgasm.
And it doesn’t have to be with a partner. Additional research has shown self-pleasure can also help with pain.
Sex can also lower levels of cortisol, the primary stress hormone – helping to ease day-after-drinking unease and worry.
Research on libido when hungover is very limited. One of the first detailed studies came from the University of Washington and the Kinsey Institute and found a combination of things were at play.
Scientists tested men’s abilities to follow instructions for controlling erections when watching porn while intoxicated and found men who had been drinking had a more difficult time controlling their arousal.
They found men who were drunk were worse than those who were sober at following instructions to get an erection or remain flaccid while viewing the X-rated content.
Intoxicated men who were told to remain flaccid actually experienced more intense erections than those who were specifically instructed to ‘rise to the occasion.’
Dr William George, lead author of the study, told Men’sHealth this effect could spill over into the next morning.
If a man was drinking excessively the night before, alcohol may not have completely left his system by the time he’s woken up, despite feeling sober.
So, the lack of erectile control as seen in the study may be responsible for the unexpected desire the morning after.
Whether man or woman, sexual desire may increase the morning after heavy partying because of a phenomenon known as alcohol myopia.
This is scientific speak for tunnel vision – when a person will hone in on one thought and ignore peripheral information.
So, if the thought of sex pops into your mind, it may be the only thing you’re able to concentrate on until you’ve scratched that itch.
A Reddit user posted: ‘Sex is the only thing I can think about and is the number one priority for the day no matter what is going on that day.’
‘Nothing better than hangover orgasms,’ one Reddit user posted – to which another replied: ‘Can confirm, just had one.’
Another poster wrote: ‘I’m the same and I’m not a young man anymore but if I’m really hungover I can jerk off like 10 or 12 times in less than a six-hour period. Hell, I’ve even finished and was going at it again in less than a minute.’
Emily Morse, a sexologist, said: ‘For a few minutes, you get to feel something other than a pounding headache and a sour stomach.
‘You’re temporarily released from your physical hangover purgatory, making the regular sensations of sex feel like a godsend.’
Similar to dopamine seeking, Dr Hafeez said people who are hungover may turn to sex for comfort or distraction, which could provide temporary relief from hangover symptoms.
Lastly, Dr Hafeez said societal expectations could be an influence.
She told this website: ‘Cultural attitudes and social norms surrounding alcohol consumption and sex can influence individual behaviors.
‘In some cultures or social circles, drinking alcohol and engaging in sexual activity may be closely linked or viewed as acceptable forms of recreation, leading some individuals to associate the two activities, even when experiencing a hangover.’
No matter the reason, Dr Hafeez said having sex is ‘unlikely to address the underlying physiological causes of a hangover,’ which include dehydration, electrolyte imbalances, poor sleep and toxic byproducts of alcohol.
She recommends hydrating, eating nutritious foods and getting adequate rest.