Vardenafil (Levitra) is a PDE5 (c-GMP selective phosphodiesterase-5) inhibitor, comparable in effect and indication to sildenafil, tadalafil, and avanafil. Vardenafil is approved to treat erectile dysfunction (ED), helping men to have penile erections and ameliorate relationship and sexual issues cause by ED. Vardenafil works directly on the penis through the nitric oxide pathway, and does not treat or address related issues of low sex hormone levels (hypogonadism), low libido, fertility (with possible exceptions), or some types of psychogenic erectile dysfunction.
In the penis, when sexual stimulation occurs nitric oxide is released, stimulating guanylate cyclase release; guanylate cyclase interacts with cyclic guanosine monophosphate (c-GMP) to relax the smooth muscles lining the blood vessels of the penile corpus cavernosum and leading to erection. The PDE5 enzyme, also known as c-GMP selective phosphodiesterase5, causes breakdown of c-GMP; through inhibition of PDE5, PDE5 inhibitors raise c-GMP levels and the threshold and duration of erections as well as increasing penile hardness.
Vardenafil is both safe and effective according to data published Sperling, et al (2010), in a typical population group of men diagnosed with ED:
Men with erectile dysfunction (ED) are typically older and have one or more underlying cardiovascular conditions. To determine the efficacy and safety of a new orodispersible tablet (ODT) formulation of vardenafil for the treatment of ED, and whether age, or the presence of underlying conditions affects treatment outcomes. Adverse events (AEs) were mostly mild to moderate in severity, occurring with higher incidence in the vardenafil vs. placebo group. The most frequently reported drug-related AEs in the vardenafil group were headache, flushing, nasal congestion, dizziness, and dyspepsia, consistent with the known safety profile of phosphodiesterase type 5 inhibitors. ... Vardenafil ODT significantly improves erectile function in men with ED regardless of age, baseline ED severity, or underlying condition.
Vardenafil and other PDE5 inhibitors are often used together in combination treatments; this is often the case in prostatectomy patients who experience ED (Albaugh, 2010):
Erectile dysfunction is the most common side effect after prostatectomy. There are currently five categories of available treatment options for erectile dysfunction for men following radical prostatectomy. The first and most common treatment is oral phosphodiesterase type 5 inhibitors (sildenafil, vardenafil, or tadalafil). Despite their popularity, these medications do not always produce an erection sufficient for intercourse after prostatectomy. The second treatment option is the noninvasive option of either a venous constriction band or the vacuum constriction device. Both treatments use a venous occlusive tension band or ring to maintain erection by retaining blood in the penis. The vacuum constriction device also utilizes external suction pressure to create an erection prior to application of the tension ring. The third treatment option is Muses, an intraurethral suppository containing alprostadil that dilates the penile blood vessels. The fourth treatment option involves penile injections. The fifth treatment is the penile prosthesis, in which artificial rods are surgically implanted into the corpora cavernosa to provide penile rigidity. Oral agents, the vacuum device, Muse, and injections have been used for penile rehabilitation to encourage spontaneous return of erectile function in men after radical prostatectomy with varied success. Untreated erectile dysfunction after radical prostatectomy has been associated with penile atrophy and further diminished erectile function. Therefore, it is critically important that clinicians provide comprehensive information about the positive and negative aspects of all treatment options and the penile rehabilitation potential of each. This will enable patients to make informed treatment choices about early intervention for erectile dysfunction.
Foresta, et al have successfully demonstrated that vardenafil and similar drugs may be of use in treating infertility concerns caused by sperm defects because it increases motility parameters and other functional parameters:
Semen samples of ten normozoospermic subjects were incubated with Tadalafil and Vardenafil at concentrations ranging from10-6M, to 10-12 M for up to 6 hours. We assessed the expression of PDE5A isoforms, the localization of the protein in the sperm cell, and evaluated the effect of the exposure to PDE5 inhibitors on sperm motility, intracellular cGMP and calcium levels, capacitation, acrosome reaction, apoptosis and fertilizing ability of human spermatozoa. Results: Isoforms A1 and A2 of the enzyme are expressed in the neck and acrosomal region of spermatozoa. The percentage of progressive motility, velocity parameters (VSL, VCL and VAP) and intracellular calcium concentration were significantly higher in sperm incubated with PDE5 inhibitors 10-6M compared to control sample at each time point. No differences were observed in both sperm capacitation and acrosome reaction, apoptosis and hamster egg penetration test. We showed for the first time the localization of PDE5A in human sperm and that its pharmacological inhibition positively influences sperm motility and intracellullar calcium concentration likely due to the enhancement of intracellular cGMP levels.
Vardenafil is a commonly prescribed, safe, and effective option that may work better in some cases than competing PDE5 inhibitors. Increased availability and diversity of PDE5 inhibitors reflects a trend of increasing focus on male reproductive health. Compared to other options, oral PDE5 inhibitors may be a more attractive option for early intervention to some patients.
 Sperling H, Gittelman M, Norenberg C, Ulbrich E, Ewald S. Efficacy and Safety of an Orodispersible Vardenafil Formulation for the Treatment of Erectile Dysfunction in Elderly Men and Those with Underlying Conditions: An Integrated Analysis of Two Pivotal Trials. J Sex Med. 2010 Aug 30.
 Albaugh JA. Addressing and managing erectile dysfunction after prostatectomy for prostate cancer. Urol Nurs. 2010 May-Jun;30(3):167-177, 166.
 Foresta C, Pati MA, Perilli L, Menegazzo M, Zuccarello D, Ferlin A, Garolla A. Expression of phosphodiesterase type 5A in human spermatozoa and influence of its inhibition on motility and functional sperm parameters. J Endocrinol Invest. 2010 Jul 1.