There's a lot of buzz these days about the new "female Viagra". The announcement of FDA trials for Lybrido/Lybridos raised hopes that the new drugs will be approved to help women’s sexual function and desire. In order to determine if these drugs will really help women, we need to better understand what actually drives women’s sexuality. First, some shocking news: sexual desire in men and women is very different.
The low down: men do not usually suffer from a lack of desire (although with low T this can happen), they suffer from erectile disorders, or ED. In other words, plumbing issues from lack of blood flow to the penis. Drugs like Viagra and Cialis increase blood flow to the penis by causing vasodilation of the arteries in the penis. Contrary to popular belief, ED drugs do nothing to increase desire.
In contrast, women usually have proper blood flow and do NOT get arousal disorders, which are characterized by the genitals not getting proper blood flow or feeling. This is not very common in women. Most often women (95%) have hypoactive desire disorders, or a lack of desire for sexual intimacy. This is usually due to very low levels of Testosterone in the body. Testosterone levels begin declining in most women during the 30s, as the ovaries slow down the production of testosterone. In order to properly address HSDD, one must replace Testosterone.
Serotonin and Dopamine also play instrumental parts in sexual desire. Dopamine is the “lust” hormone that creates the impulse of wanting to have sex – often described as feeling “horny”. Serotonin causes control and inhibition, which in turn will cause a drop in sexual desire. These two hormones work in conjunction to create a fine line balance between lust and control, so we don’t become nymphomaniacs, but still have the desire.
So let’s look at Lybrido and Lybridos. Lybrido has a coating of a small amount of Testosterone encasing a substance similar to Viagra. Lybridos has the Testosterone coating covering Buspar, (an anti-anxiety med) which temporarily lowers serotonin.
In theory, Lybridos would temporarily lower serotonin, while the T coating would temporarily increase desire. Lybrido alone does not alter these hormones, but does increase Testosterone. The Viagra like substance aids blood flow, but again this is not the most important issue for women.
These drugs do have some interesting promise. However, before we start giving drugs to women to treat the desire disorders, one needs to investigate the root cause. Desire is a much more complex issue for women than it is for men.
We need to address psychological issues for low desire, including bad relationships, emotional traumas such as rape or sexual abuse, and medical issues like chronic illness or side effects of medication, etc. Treating women with Testosterone or any other drug will not work, if these issues are not identified and addressed first.
Happily, most women can be treated with bio-identical testosterone alone and do not require these other components. We need to look at what we are trying to accomplish before determining the best course of treatment. Are we trying to create normal physiology or an unnatural balance in our bodies driving sexual desire? As a physician, I believe normal physiology is the most desirable outcome.