Results of Clinical Studies about the Effect of Viagra, Cialis, and Levitra on Women
Phosphodiesterase Inhibitors (PDE5-inhibitors) such as Viagra (sildenafil), Cialis (tadalafil), and Levitra (vardenafil) are thought to improve blood flow to clitoral and vaginal tissues through a similar mechanism to that found in male genitalia. This increased blood flow in healthy women has been associated with a heightened level of sexual arousal. It is through this mechanism that PDE5-inhibitors are being explored for use in female sexual dysfunction (FSD), as well as for increased sexual experience in healthy women.
Viagra has been evaluated in only one trial with healthy women, though its use in patients with female sexual arousal disorder (FSAD) has been explored by several clinical studies using various measures of efficacy, in women at different stages of menopause and with various underlying conditions. The safety and efficacy of Cialis for FSAD has been evaluated in 3 studies. Levitra use has been examined in one study of women with hypoactive sexual desire disorder (HSDD). Here is a summery of available studies on effect of PDE5-inhibitors in females.
Viagra in Healthy Women Without Sexual Dysfunction
Many individual accounts report the success of Viagra in increasing sexual experiences in healthy women (with no FSD), though its use in this setting has only been evaluated in one controlled trial to date. The use of Viagra 50 mg versus placebo was evaluated in 68 women (average age 28 years) without signs of sexual dysfunction. Compared with placebo, Viagra treatment showed:
significant improvements in arousal, orgasm, and enjoyment
no significant improvements in desire, frequency of intercourse, or frequency of fantasies
Mild/moderate headache, nausea, and vision problems.
Viagra, Cialis for Female Sexual Arousal Disorder (FSAD)
FSAD is characterized by an insufficient lubrication-swelling response to sexual excitement, so treatment with Viagra or Cialis to improve sexual arousal in females has been evaluated in 5 clinical trials of approximately 1270 women. Patients included pre and post-menopausal women ranging in age from 22 through 70 years, and treatment doses ranging from 10-100 mg of Viagra and 5 to 20 mg of Cialis. Most frequently reported adverse events were mild to moderate in severity and included headache, flushing, rhinitis, nausea, and visual disturbances. Various measures of sexual arousal were used in the studies, with various degrees of reported success.
In women with FSAD and hypoactive sexual desire disorder (HSDD), Viagra showed no significant improvements in arousal.
In women with FSAD without HSDD, Viagra showed:
In women ages 22-28 years, Viagra showed:
In a study of 577 women receiving estrogen replacement therapy (ERT) and 204 estrogen-deficient (ED) women, Viagra showed :
In dynamic MRIs to quantify sexual arousal, Viagra did not improve clitoral engorgement beyond that of placebo (engorgement: 89% with Viagra vs. 84% with placebo).
In an unpublished study of 214 women, Cialis did not demonstrate significant improvements in attaining and maintaining arousal.