Hello and happy Friday! Here's a question from a reader:
A: Ohhhh this is a fun and complicated topic.
Before I get to the actual whyyyyyyyy, let me explain to readers that SSRIs are selective serotonin reuptake inhibitors, which, long story short, means they increase serotonin in the brain. They’re most often used as anti-depressants, and it’s well known that they can come with sexual side effects, such as reduced sexual desire and delayed orgasm. If you’ve ever been prescribed a SSRI, hopefully your prescriber talked with you about such side effects.
Okay so the real answer to your question is we don’t know for sure, but researchers have a couple of good ideas.
(With apologies to any neuroscientist or psychiatrist reading this, I’m going to talk about neurotransmitters metaphorically, to make them more understandable to people who aren’t neuroscientists or psychiatrists. Neuroscientists and psychiatrists, this post is not for you.)
Biochemicals like serotonin and dopamine have personalities, the way people have personalities—which is to say, here are some consistencies in how they behave across all situations, but also differences, depending on the situation. Some aspects of an individual’s personality come to the forefront in some situations and others come to the forefront in other situations, right? If your personality is that you’re very loyal, sometimes that comes out as affection and cheering for the people you’re loyal to, and sometimes it comes out as mamma bear snarling at a threat. But they’re both loyalty.
Serotonin’s overall personality is very chill. It has no sense of urgency, it just likes things to keep flowing along.
In your pineal gland, serotonin’s chillness shows up when he’s the first guy at the party to be like, “It’s getting kinda late, anybody else ready to call it a night? ’Sup, Melatonin?”
In your gut—and most of your body’s serotonin is in your gut—it nudges its cell and whispers, “Hey, let’s give our neighbor a little hug, huh?” Widespread serotonin-motivated gastrointestinal hugging results in peristalsis, the gut contractions that keep things moving.
(Dear neuroscientists and psychiatrists, I know. But this isn’t for you! It’s for people who never had to learn what “reuptake” is and want to understand why serotonin messes with their orgasms.)
Its effects on sex seem to come from its action in a variety of places, both central (in the brain and spine) and peripheral (out in the other parts of your body.)
Peripherally, serotonin behaves a little like how it behaves in the gut. It’s the Olaf of hormones. It likes warm hugs. It promotes the kinds of contractions that keep things moving, both in the muscles involved in the contractions of orgasm and in bloodflow. And here’s something I didn’t know until I now: though SSRIs increase serotonin in the short-term, they can actually reduce it in the long term, in specific situations (and not in others; or maybe it’s different pathways; it is not simple). So it could be, maybe, that part of whyyyyyyy SSRI use impacts sexual functioning is that they actually reduce the serotonin in your body, which reduces your body’s ease of keeping things flowing, moving the contractions along. Or it could be that increased serotonin messes with your nitric oxide production, which facilitates vasodilation (bloodflow). Maybe.
And then up in your brain is where the money is, when it comes to serotonin and sex. It some areas of the brain, increased serotonin results in decreased dopamine and norepinephrine, both of which have super-not-chill personalities. Dopamine is just a big ol’ wanting; I often compare it to a cat who MEOWS at the door, demanding to be let out, then MEOWS at the other side of the door, demanding to be let in. It just keeps wanting. And norepinephrine’s personality is “On your mark! Get set!”
So if increasing serotonin reduces dopamine and/or norepinephrine, you get a lot more chillax and a lot less MEOW CAT WANT and On-Your-Mark-Get-Set.
(Neuroscientists and psychiatrists, why are you still here?! This is not for you! It must be driving you bananas! Go read this instead.)
People vary. Some people experience no sexual side effects. Some people experience them at first and then they go away pretty early in treatment. Some people experience the side effects for as long as they take the medication. And a small proportion of people may continue to experience these side effects even after they stop taking the medication.
In the broadest terms, serotonin lets you step to one side of urgency. It is chill. Sexual response, from desire to orgasm, is about losing your chill.
In a future post, I’ll talk about what to do about the side effects—short answer, forget about sexual response, just focus on PLEASURE, serotonin digs pleasure—but this question was about the whyyyyyyyyyy.
Hope it helps!
EMILY NAGOSKI is the award-winning author of the New York Times bestselling Come As You Are and The Come As You Are Workbook, and coauthor, with her sister, Amelia, of New York Times bestseller Burnout: The Secret to Unlocking the Stress Cycle. She earned an M.S. in counseling and a Ph.D. in health behavior, both from Indiana University, with clinical and research training at the Kinsey Institute. Now she combines sex education and stress education to teach women to live with confidence and joy inside their bodies. She lives in Massachusetts with two dogs, a cat, and a cartoonist.