The Food and Drug Administration has approved a pill that aims to increase a woman's desire for sex — a controversial decision made only after an extended lobbying campaign by the drug's makers.
But the agency's imposed an unusual number of restrictions on who can prescribe the drug and how they can prescribe it — moves aimed at minimizing concerns over its side effects.
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The pill's called flibanserin and will be marketed under the brand name Addyi. The FDA is asking its maker, Sprout Pharmaceuticals, to specially train doctors and pharmacists who dispense it and to keep track of any problems with women taking the drug. Only trained physicians will be allowed to write prescriptions for the pill.
The FDA is also requiring a strong warning to women that they should never drink alcohol while taking the drug and stressing the risk that it can cause sudden fainting - a special danger for drivers.
The FDA had rejected the drug twice before. Sprout, which bought rights to the drug when pharma giant Boehringer Ingelheim dumped it, helped wage a public relations campaign called "Even the Score." It claimed that while men have many different sexual dysfunction drugs to choose from, including Viagra and Cialis, women have none.
"Today's approval provides women distressed by their low sexual desire with an approved treatment option," said Dr. Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research.
Critics said Addyi shouldn't win approval because of its side effects and because its benefits were modest. But the FDA said there's no other drug to help women with a severe lack of sexual desire called hypoactive sexual desire disorder.
Dr. Susan Wood, a former FDA official now at George Washington University, said she was disappointed by the approval.
"This is a product that is neither very effective nor particularly safe," Wood told NBC News.
"It won't benefit many women and at the same time the approval comes with a lot of restrictions, setting a precedent that a drug for women's sexual health has to be treated in a very special way," Wood said.
Wood and Dr. Philip Hanno, a urologist at the University of Pennsylvania's school of medicine, both say the FDA was pressured into approving the drug. Hanno is one of the FDA advisers who voted against recommending approval of Addyi last June.
"I think the FDA was under a lot of pressure," Hanno told NBC News. "This 'Even the Score,' the group which apparently was supported by the pharmaceutical company among others, was very influential and they certainly had a lot of people at the advisory committee meeting who made comments."
The drug is far from being an aphrodisiac. "Hypoactive sexual desire disorder is characterized by low sexual desire that causes marked distress or interpersonal difficulty and is not due to a co-existing medical or psychiatric condition, problems within the relationship, or the effects of a medication or other drug substance," FDA says.
"HSDD is acquired when it develops in a patient who previously had no problems with sexual desire."
In other words, women like Katherine Campbell. Campbell, 31, thinks she could benefit from the drug.
"One day I had this great, awesome sex drive and a great relationship with my husband and the next day, I didn't even think about it any more," she said.
She and her husband Christopher, who live in Indianapolis, noticed the change after their first son was born. "I lost not only a very intimate part of my relationship with my husband, but also a lot of my confidence. My sexuality as a woman changed," Campbell, who has campaigned for the drug's approval, told NBC News.
Studies show that on average Addyi increased the number of so-called satisfying sexual events by half to one additional event per month over placebo.
It doesn't work like Viagra and other men's erectile dysfunction drugs. They work by increasing blood flow all over the body, including to the genitals, helping improve a man's physical ability to have sex. Flibanserin modifies serotonin, a message carrying chemical in the brain. It's believed to act over time to increase a woman's ability to become sexually aroused.
"If someone has low sexual desire because they hate their partner, sex hurts and their life is a mess ... the pill is not going to help them," said Dr. Lauren Streicher of Northwestern University.
"This is a huge advancement in women's health because for the first time we have an FDA approved, non-hormonal option for women who have this very distressing lack of sexual desire," Streicher said.
"And as a sexual health expert, as a gynecologist, as someone who takes care of women every single day ... this is going to be a game changer for me because right now I have women that come into my office and have these issues and I just say, 'I'm so sorry. There is nothing that I can do.'"
The company says it will aim to price Addyi to compare to the cost of Viagra. They anticipate it'll probably be covered by health insurance companies with a co-pay of $30 to $75. Sprout says it should become available in October.
This story originally appeared on NBCNews.com