It's being billed as a big day in the sex lives of women: The Food and Drug Administration just approved the first-ever drug designed to boost a woman's libido.



The medicine in question is called flibanserin, a daily pill made by Sprout Pharmaceuticals for premenopausal women with hypoactive sexual desire disorder, or the sudden and unexplained loss of libido.

The drug, which will be sold under the brand name Addyi, hits pharmacy shelves on October 17. There's just one problem: The pink pill doesn't actually work all that well. The FDA had rejected flibanserin twice before, and only approved it this time after a powerful marketing push and advocacy campaign from women's groups.



Here are five reasons to be skeptical that a Viagra equivalent for women is on its way to market.

1) The drug doesn't appear to help most women

According to an FDA analysis of flibanserin, between 8 and 13 percent of women who take the drug will see some improvement over placebo. That's a pretty small number, particularly when you consider how "improvement" has been defined.

Specifically, women who take the flibanserin pill have, on average, 0.5 more "sexually satisfying events" per month. While this is greater than those taking a placebo comparison pill with no active drug in it, that's a pretty negligible boost.

For this reason, Dr. Adriane Fugh-Berman — the director of the PharmedOut project at Georgetown University who studied the marketing campaign around flibanserin — has called the drug "a mediocre aphrodisiac with scary side effects."

2) The drug has scary side effects

Let's be clear up front: No drug is without side effects. But every medicine is a balance of risks and benefits. And as Walid Fouad Gellad, an internist in Pittsburgh who has written about flibanserin in JAMA, noted, given the fact that flibanserin doesn't seem to do all that much to alter women's sex drives, there's a big question about whether its side effects are worth the risk.



"If you're going to give something to women and they can pass out any time, that’s a real problem" Research to date has shown that about one in five women who took the drug reported adverse effects. Most commonly these included drowsiness, dizziness, and fainting, which increased the risk of injuries such as concussions. Extremely low blood pressure was another, less common side effect.



"If you're going to give something to women and they can pass out any time, that’s a real problem," Gellad remarked.

What's worse, these side effects are exacerbated when the drug is taken with alcohol and hormonal contraceptives — and many, many women drink alcohol and use these types of birth control.

3) Doctors worry about interactions with alcohol and hormonal contraceptives

The FDA's workaround for some of these side effects has been that women are asked to take the drug at bedtime and that it will only be available through specially certified health-care professionals and pharmacies who have gone through some training. Doctors will need to assess the ability of patients to stay away from drinking while on flibanserin.

But how this actually plays out in the real world is another question. Women may still drink on this medication, they may take it in the morning — there's no way to control those behaviors.

The drug may also be used "off label" — or prescribed in ways that are different from how it's been approved. This could include women who are menopausal or who have other medical problems, like a heart condition. "The drug can cause low blood pressure, so that really worries me if you give the drug to women who have a cardiac condition," said Fugh-Berman.

What's more, the evidence the company provided about the drug's impact on alcohol interaction was pretty strange and didn't tell very much about how alcohol will actually affect users. The study involved 25 participants, but only two were women. It confirmed that alcohol can boost the risk of bad side effects with flibanserin, but a study of mostly men for a drug for women means it's still unclear how women who drink will react.

Finally, the trials on flibanserin have been limited to healthy women who aren't on sleep aids or anti-anxiety drugs or all the other medications many American women rely on and that may interact with flibanserin. So there's also some question about whether other side effects and complications will emerge. And we have no idea about flibanserin's long-term side effects, since the studies we have to date have only run for short periods of time.



This isn't all that unusual for a new drug, but it becomes more relevant when you consider the drug's lackluster effect on libido.

4) The campaign behind the drug is misleading

The FDA had already rejected the drug twice for failing to be effective enough, most recently in 2013.

While the drug company has provided no new efficacy data since then, the pill's luck changed in June when an FDA advisory panel urged the regulator to approve flibanserin.

The panel's 18-6 vote was considered a "major victory" because the FDA more often than not adopts the advice of the expert group and because the same panel had voted unanimously against flibanserin in the past.



It was also a major victory for advocacy and marketing over science. That's because while the evidence didn't change since the 2013 rejection, the drugmaker did launch the "Even the Score" campaign. Its main objective: to level the playing field when it comes to sexual dysfunction drugs for men and women, and get the drug approved. "There are 26 FDA approved drugs to treat various sexual dysfunctions for men," the campaign's site reads, "but still not a single one for women's most common sexual complaint."

This is misleading. The playing field is actually even in this regard, and flibanserin is the first drug approved to boost the sex drive of either sex. While the group claims that men have this grab bag of medications at their disposal, as this piece in JAMA explained, "There are no approved products for low sexual desire in men." The pills available to men mostly deal with mechanical problems, like erectile dysfunction or low testosterone — not flibanserin's elusive goal of boosting sex drive.

The Even the Score campaign also accused the FDA of being sexist for not getting the pink pill on the market to help women: "Why do we fast track the approval of drugs like Viagra (1998) for men? Why do we accept fewer patients in trials for male drugs than we've seen for some for women?" reads the campaign website.



But as Paul Thacker described at Slate, the medical experts he spoke to agreed flibanserin is no "cure-all" and that the FDA has been evidence-based in its treatment of the pill. "It is hard to see what is sexist about the national drug regulatory agency refusing to approve a drug that was ineffective and like all active pharmaceutical products, has the potential for harm," one doctor told him.

5) It’s been called a "textbook case of disease-mongering" by Big Pharma

For years, "female Viagra" has been discussed in the scientific literature as "a textbook case of disease-mongering by the pharmaceutical industry."

Critics have accused the pharmaceutical industry of inventing the medical condition (hypoactive sexual desire disorder) that the drug is designed to treat.

"The FDA has turned this down twice before, and now we have no new evidence of benefits, and we have more evidence of harms, so if the FDA does approve the drug today the only thing that changed is the amount of pressure put on it by a corporation though a major PR campaign," said Fugh-Berman.

For Gellad, this doesn't necessarily mean the drug should not have been approved. Women with low sex drives have no other treatment options, after all. "It would have been very different if there were already six or seven drugs for this condition," he said. But then the question becomes whether a drug with small benefits and many side effects is better than no drug at all.

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