What does 'female Viagra' treat, exactly?

The so-called “female Viagra” proposed to treat women with hypoactive sexual desire disorder hung in medical purgatory until Thursday, when an advisory panel recommended that the FDA approve the drug. The FDA had previously rejected the pill—properly known as flibanserin—twice before. Many hope this verdict will finally propel it to market.

There are currently zero—count that, zero—FDA-approved drugs to treat sluggish sex drives in women, while there are at least seven to tackle men’s erectile dysfunction. Whether or not the FDA has been holding flibanserin to more rigorous standards than it did for, say, actual Viagra (which passed after just six months of research)—well, my colleagues at other outlets have debated that extensively.

But in reading recent coverage, apart from taking a side in the debate, you might have thought: “Hold up, what is hypoactive sexual desire disorder? Do I have it?” Who can’t relate to the stress of trying to keep your sex life alive while holding down a couple of jobs plus school or trying to break through that glass ceiling? Is nothing easy?

No. But there’s a distinction between grappling with the everyday ebbs and flows of sexual desire and suffering from a medical disorder. We spoke with physicians about the diagnosis, and here’s what you need to know.

What is hypoactive sexual desire disorder?

Hypoactive sexual desire disorder, or HSDD, is a condition defined by an absence or reduced interest in initiating, responding to, and enjoying sexual activity. One must present these symptoms consistently for at least 6 months for the situation to be flagged as a disorder.

So, no, a couple of tough weeks here and there don’t count—that’s just life. But according to a study from 2008, almost 10 percent of women between the ages of 18 to 44 suffer from HSDD. Flibanserin is designed to treat these pre-menopausal women.

Desire matters more than arousal

One key to understanding human sexuality is understanding the difference between desire and arousal. “Desire is interest,” said Amy Rosenberg, a psychotherapist and the co-director of the Program in Human Sexuality and Sex Therapy at NYU Langone Medical Center. “It’s like when you’re out with your partner and you really want to run home and start touching them. That’s desire. The arousal is the physical response that kicks in once you start touching them.”

But what drives the female libido? “First of all, it is a lot of different things, so it’s a little difficult to characterize,” said Andrew Goldstein, director of the Centers for Vulvovaginal Disorders. “If you’re feeling horny, that’s ‘spontaneous desire.’ Maybe it’s with a longterm partner or maybe you are on Tinder, or maybe you just have the inclination to masturbate.”

But there’s also what the doctor called “receptive desire,” which is more like you and your partner are sitting on the couch on a Tuesday night, he or she initiates sex and maybe you’re not super into it—but you know it will make your partner happy and want that closeness, so you engage and then you enjoy it.

For women with HSDD, flibanserin targets the absence of sexual desire, both spontaneous and receptive. Yet while actual Viagra boosts arousal by increasing blood flow to the penis—essentially a mechanical function—flibanserin targets women’s brains (more on this below).

What causes a lack of desire?

That’s the first question a woman tackles with her doctor when she seeks medical treatment for a sexual disorder. Is it physical—like you have pain during sex? Is it biological—like your neurotransmitters are imbalanced or your hormones are off? Is it psychological—like you’re stressed about your job, the dishes in the sink, or your relationship? “To have good sex you kind of have to be able to shut the world out,” said Goldstein.

Desire can also be affected by medications. Some birth control pills, for example, will lower your testosterone levels and decrease your sex drive. And anti-depressants such as SSRIs can impede your ability to orgasm.

It’s also possible that a woman’s lack of desire could be a symphony of all these factors.

What does treatment look like?

If a woman’s lack of desire stems from situational or psychological factors, Goldstein recommends therapy or couples counseling, mindfulness, and meditation. When it’s linked to a medication she’s taking, treatment can be as simple as switching to a different form of birth control or rejiggering prescription and dosage.

But some women’s lack of sexual desire can be attributed to biology, said Irwin Goldstein, president and director of the Institute for Sexual Medicine in San Diego—specifically, an imbalance of neurotransmitters in the brain. That’s where flibanserin and the FDA come in. Flibanserin would target the dopamine levels in these women’s brain to boost sexual desire. As you may know, dopamine is a feel-good hormone and neurotransmitter often associated with euphoria.

How many women would be potential candidates for flibanserin?

When pressed on the percentage of patients they’d consider for flibanserin treatment, both Dr. Goldsteins said the number was difficult to pin down. But Andrew Goldstein told Fusion that after screening out women with abnormal hormone levels (such as low testosterone), women suffering from depression, and women experiencing relationship or personal stress, he thinks he’d recommend the drug to roughly 50 to 55 percent of his patients.

Until now, the FDA has denied the drug because it had too many side effects (nausea, dizziness, and drowsiness) and the benefits were marginal. The advisory panel still holds that benefits of filbanserin are limited, but that for those who respond positively to the treatment, effects are meaningful.

Andrew Goldstein puts it like this: Say you have a patient who is only having sex with her partner three times a month to please him or her. Then she takes flibanserin and has sex four times a month. While that might not seem like a significant increase, “if she had sex for that fourth time because she wanted to, actually that’s huge.”

The FDA doesn’t always listen to its panels, so there’s no guarantee that this week’s news will be a game changer. But when we asked Irwin Goldstein to predict whether flibanserin would be a viable option for young women in the next few years (you know, for a friend!), he said yes, depending on the case.

He was quick to stress, however, that sexual desire is complex—and not easily “solved” by simply taking a pill—but he wants women to have the option. And so do we.

Cleo Stiller is a digital producer covering the intersections of sex, tech and culture. Words to live by: get your money’s worth.