The mechanism of action for ED pills is simple: They inhibit the PDE5 enzyme which regulates the signals responsible for the smooth muscle tissue. In females, sildenafil may also increase blood flow to the genitals. One study suggested that Viagra may improve clitoral and uterine blood flow in healthy postmenopausal women. You should stop taking it if there’s no improvement after eight weeks. By week 6, you should start noticing a change in your arousal level and climax intensity.There are two prescription drugs on the market that have been approved by the Food and Drug Administration (FDA) to specifically address HSDD. They are available only for . Siriporn Kaenseeya/EyeEm/Getty Images The FDA has approved two drugs to address FSIAD: Vyleesi (bremelanotide) The FDA states that this medication can treat FSIAD in . Flibanserin (Addyi) is a Viagra-like drug for cisgender women and others assigned female at birth. Currently, Addyi is only available through certain prescribers and pharmacies.