Why Does Sex Make You So Sleepy?

There’s a common caricature of heterosexual monogamous intercourse, wherein after climaxing, the man collapses into pillows on a bed in a blissed-out state of pleasure, ready to drift off to sleep while the woman is wide awake, twiddling her thumbs and staring at the ceiling. Sure, that vignette is rife with generalizations of gender norms and relationship dynamics, but it does still bring about an interesting question: What does it mean if you’re more energized or tired after sex (regardless of your identity or orientation)?

When your and your partner’s energy levels don’t match following sex, it may affect your relationship in and out of the bedroom. Knowing why you may have more or less energy after sex—and how you can address any concerns or communicate needs better with your partner—is an important way to strengthen the relationship as a whole.

Hormonal reasons behind those post-sex energy levels

The hormones your brain releases during (and immediately after) sex play a role in how energized (or not) you feel after doing the deed. “During a sexual encounter, the brain releases oxytocin,” says Sari Cooper, LCSW, certified sex therapist and director of The Center for Love and Sex in New York City.¹ Oxytocin, known as the “love hormone,” helps you feel warm and relaxed by lowering cortisol (the “stress hormone”), she says.² Thus, from a purely chemical level, getting physical with your partner can help you or your partner relax enough to fall asleep.

That’s just from the sexual “encounter,” though. “If a person orgasms, there are further hormones that get released, including vasopressin, prolactin, serotonin, nitric oxide, and endorphins,” says Cooper. Vasopressin affects memories, concentration, and even aggression, which is why people often feel bonded to their sexual partners.³ Serotonin and endorphins are hormones that improve your mood. Nitric oxide promotes additional blood flow to the genitals, increasing sensation and supporting orgasm.⁴ Most importantly, prolactin is released after orgasm to help decrease desire and help you feel satisfied—again promoting that relaxed state.⁵

Everyone produces prolactin, but a person’s levels vary at different times of their life depending on whether or not they have orgasmed, if they are or have been pregnant, or if they are nursing. Since prolactin levels affect sexual satisfaction, which leads to the further release of hormones affecting energy, their effect may rely in some part on the sexual biology of the person having intercourse.⁶ It doesn’t help that heterosexual women often experience “the orgasm gap,” which contextualizes the lowered likelihood of a vagina-haver to orgasm during penetrative intercourse than a penis-haver. This would, then, make folks with a vagina less likely than folks with a penis partners to have released the hormones after cis-hetero sex that would make them tired.

Keep in mind that “we are all unique individuals, so these hormones may have different effects on people no matter what their sex,” says Cooper.

The other variables at play if you’re tired after sex

How you feel after sex isn’t as simple as chemicals in your brain. There are all kinds of variables that can affect hormone release, such as a person’s menstrual cycle, medications, or other factors. Your day-to-day sexual response is also liable to vary, and “the same person doesn’t have the same reaction every time,” says Stella Harris, an intimacy coach and author of Tongue Tied: Untangling Communication in Sex, Kink, and Relationships and The Ultimate Guide to Threesomes. “Not only can the sex be different, but the state we go into it can also affect the way we feel coming out.” That is, if you’re already tired before having sex, odds are that the sex will make you feel more tired.

The physical toll of sex can also impact your post-intimacy energy levels. “Sexual activity can be like working out and your stamina is challenged, so that when some folks are done, they are ready to sleep, and for others, they’re more wired,” says Cooper.

What’s important is to be accepting of whatever your body needs after sex. Nothing good comes from fighting against our body’s needs.

Your emotional state also affects how alert or depleted you are after sex. For example, “if one person is worried they are engaging sexually as a way of creating a deeper emotional bond, their vulnerability will be higher,” Cooper says. “If the emotional connection is not apparent or returned, falling asleep might be a way to cope with their disappointment.” Or, “if two partners share an aligned experience that makes both of them equally connected and hopeful about their relationship, sleeping can be the result of a super-relaxed state,” she says. One could also see how either of those scenarios could lead someone to be more awake, either because their head is spinning with anxiety or buzzing with excitement.

“What’s important is to be accepting of whatever your body needs after sex,” says Harris. “If you’re a jump-out-of-bed-and-go-for-a-run person, that’s great. If you need a catnap, that’s great, too. Nothing good comes from fighting against our body’s needs.” She says to plan for it as much as possible once you know your patterns. For example, if you know you need to rest after sex, you may want to account for some extra cuddling time before moving on with your day. Or if you know you feel wide awake afterwards, see if your partner is game for morning sex.

When to be concerned about post-orgasm sleepiness

It’s normal for your energy level to fluctuate throughout phases of your life, a relationship, or even the week. It’s also normal for people to have patterns they notice about themselves, such as always sleeping through the night after orgasm. However, if you think your reaction to sex or orgasm is extreme—say you’re so wired you can’t sleep at all, or unable to stay awake even if you wanted to—the experts say you may want to investigate potential causes with your health-care provider.

A condition called post coital dysphoria (PCD) is what Cooper describes as when someone “might feel deep sadness after a partnered sexual experience.” People with PCD may have symptoms like mood swings and reduced energy. There’s also a rare health condition called post orgasmic illness syndrome (POIS), which can cause exhaustion, fog, or other flu-like symptoms in people. It can last up to five days after an orgasm or sexual encounter. The cause of POIS is currently unknown, but it may be due to either an immune reaction or an allergy to another person’s seminal fluid. If you suspect either of these conditions, speak to your healthcare or mental health provider for additional support.

How to talk to your partner about being tired after sex

Let’s say you don’t feel the need to loop in a healthcare provider to get to the bottom of why you might feel tired after sex. Even so, it could be worth discussing swings in energy with your partner to make sure they understand how you’re feeling—particularly if they feel differently.

For example, you might bring up if your partner’s energy level is affecting your enjoyment of partnered sex, so “one partner’s falling asleep isn’t misinterpreted as abandonment by the other, and a burst of energy by one partner isn’t misinterpreted as lack of authentic connection,” says Cooper.

It’s important to talk about what you need in advance so you can advocate for yourself when you’re in a calm, non-sexually charged situation. For example, Harris says one solution would be that the person who tends to have a lot of energy after sex might be able to burn it off ahead of time, leaving them available for calm cuddles with their more sedate partner afterward. Or, the snugglier partner may need to compromise and have a shorter cuddling session after sex to accommodate a partner who needs less time being stationary. Cooper suggests using “I” statements, such as “I feel…” or “I would prefer…,” to avoid assumptions or projecting inaccurate intentions on your partner.

As with most aspects of relationships, communication and compromise are key to finding a solution that works for everyone, and the case of being tired after sex is no exception.