Female Viagra: Safety and Effectiveness

In 2015, the FDA approved flibanserin (Addyi), also known as “female Viagra,” for marketing after two previously failed attempts. Based on the theory that low libido in women, which is dubbed hypoactive sexual desire disorder (HSDD), is a result of an imbalance of neurotransmitters in the brain, flibanserin works by manipulating a variety of serotonin receptors, with some manipulated by excitation, while others are manipulated via inhibition. According to the prescribing information from Valeant Pharmaceuticals, the “mechanism of action in the treatment of premenopausal women with hypoactive sexual desire disorder is not known.”

How does flibanserin (Addyi) work?

Yes, this is true. But this is true for a lot of medications. Almost one in five medications lack a well-defined mechanism of action. However, flibanserin does not work anything like sildenafil (Viagra), (vardenafil) Levitra, and tadalafil (Cialis) do, which is by causing increased blood flow to the penis and whose mechanisms of action are well understood. But if a medication works by an unknown mechanism, the FDA still can approve it if there is a good safety record and if the drug is proven to be effective.

Safety and effectiveness

Regarding safety, a woman shouldn’t take this drug if she drinks alcohol; treats an HIV-1 infection; treats Hepatitis C; takes antifungals, certain antibiotics, antihypertensive medications, certain antidepressants (especially the SRIs); or has liver problems. Side effects of this product include fatigue, sleepiness, low blood pressure, fainting, dizziness, nausea, and insomnia.
Although its mechanism of action is not known, what is known is that there are many side effects, warnings, and contraindications listed for flibanserin. If a person has a genetically-caused deficiency in some of the liver proteins involved in the liver’s ability to detoxify chemicals, there are hundreds of medicines he or she shouldn’t take, and flibanserin is one of them.
There was so much concern about its safety that the FDA required a “black box” warning on its accompanying circular.

What about its effectiveness?

The average benefit of this drug in its studies was a half to one extra satisfying sexual event a month compared to placebo and, at best, an improvement in satisfaction and desire in 10% of women.

Who should take it?

Patients who should take this drug are pre-menopausal women who suffer from a “acquired, generalized hypoactive sexual desire disorder (HSDD), as characterized by low sexual desire that causes marked distress or interpersonal difficulty and is not due to a coexisting medical or psychiatric condition, problems within the relationship, or the effects of a medication or other drug substance.” 
Like all drugs, it’s a matter of risk-vs-benefit. For the women who will not experience a positive result with this drug, the biggest loss is the $30/day price tag (one pill each night).

What’s all the ruckus about?

While this drug may be expensive, the ability to express intimacy physically is priceless to many.
Nevertheless, the FDA-approval was very controversial. After two failed attempts at approval, the third, which proved to be the charm, was met with skepticism by those who accused the government agency of “selling out” to Big Pharma pressure and marketing hoopla.

One-way flibanserin is just like Viagra

Drugs like sildenafil (Viagra), (vardenafil) Levitra, and tadalafil (Cialis) should always be prescribed under the watchful eye of a physician since the use of drugs needs to balance with other medications that can be addictive when treating high blood pressure, such as nitrates.

With so many possible reactions to flibanserin, the same is required. It’s the whole point of making some drugs prescription-only. In fact, there is another requirement that a physician to must meet to prescribe flibanserin: he or she must be certified by a special course about its safety concerns. This is good practice, and with good practice, the risk-vs-benefit ratio can tip over toward the safety zone by the right surveillance. Men taking Viagra and women taking flibanserin both need to be monitored for different reasons, but the crucial thing is that they each have to be monitored with the same level of physician involvement.

How does this portend for the future?

The final study of any medication—that is, the consumer market—is when millions participate. Market numbers always dwarf the numbers of study selection, and as the benefits and negatives of flibanserin become increasingly clear, it all will contribute to the scientific literature on HSDD, enabling for the further tweaking of the drug to improve its safety and efficacy.