There were two interesting studies I came across recently. The first one shows maca has a small benefit in men with impotence, and the second one shows maca to be helpful in reversing some of the sexual dysfunction associated with the use antidepressant medications.
Italian scientists at the Department of Urology, Morgagni-Pierantoni Hospital, in Italy, wanted to find out the effects of maca extract on well-being and sexual performances in patients with mild erectile dysfunction. They gave 50 men with mild erectile dysfunction (ED), maca dry extract, 2400 mg a day and compared them to a placebo group. After three months, those on maca experienced a significant improvement in physical and social performance-related sexual score compared to those who did not receive the herb. They say, "Our data support a small but significant effect of maca supplementation on subjective perception of general and sexual well-being in adult patients with mild ED.
In the second study, Dr. Dording and colleagues at the Department of Psychiatry, Massachusetts General Hospital, in Boston, wanted to find out whether maca is helpful in patients who have sexual dysfunction as a result of taking SSRI drugs for depression. SSRI drugs, such as Paxil, Zoloft, and Prozac, influence serotonin activity in the brain. Excess serotonin inhibits sexuality. One group received 1.5 g/day and another group took 3 grams a day. Those taking 3 grams a day had a reversal of their dysfunction. They conclude, "Maca root may alleviate SSRI-induced sexual dysfunction, and there may be a dose-related effect. Maca may also have a beneficial effect on libido."
My comments: I like maca herb and I have personally noticed a mild sexual enhancement and energy from it. But, in my opinion, it is not as potent as some other herbs such as tribulus, mucuna, horny goat weed, catuaba, muira puama, yohimbe, and tongkat ali. Maca is a gentle herb and perhaps it may be safer to use in those with SSRI induced sexual problems. It is possible that low dosages of other herbs may also be effective and not cause unpleasant interactions with the medications. If you take any prescription medications or hormones, or are over the age of 50, have mild high blood pressure, be careful when using aphrodisiac herbs and always begin with low dosages for a few days. If the small amounts are not effective, then you can increase the dosage little by little. Have approval by your health care provider. If you have moderate to severe high blood pressure or a heart condition, it may be best not to use these herbs since they can increase heart rate and in very high amounts cause heart rhythm disturbances. See http://www.raysahelian.com/maca.html