Sildenafil

Sildenafil citrate is a vasoactive medication belonging to the drug class of phosphodiesterase – 5 enzyme (PDE-5) inhibitors; it is a competitive antagonist of this enzyme. PDE-5 can be found all over the human body especially in the corpus cavernosum within the penis, striated and smooth musculature, as well as in platelets. However, PDE-5 has the largest distribution in the penile corpus cavernosum which is why sildenafil citrate is able to work selectively in this part of the body.

Vardenafil

Vardenafil belongs to the phosphodiesterase type 5 (PDE5) inhibitors drug class, a class of drugs commonly indicated for treatment of erectile dysfunction (ED). It is a selective phosphodiesterase (PDE) type 5 inhibitor similar to sildenafil and tadalafil. This class of drugs does not inhibit prostaglandins as do some agents for treating ED (e.g., alprostadil). Vardenafil and tadalafil are more selective for PDE5 than PDE6, which is present in the retina. This leads to less visual adverse effects such as those reported in sildenafil-treated patients. The advantage of vardenafil may be that it achieves maximum plasma concentration sooner than sildenafil and tadalafil which may result in a faster onset of action. In an analysis of 580 patients, erections improved in 80% of men, and the ability to complete sexual intercourse with ejaculation was increased. Efficacy in treating diabetics and radical prostectomy patients has also been demonstrated. According to ED treatment guidelines, oral phosphodiesterase type 5 inhibitors (PDE5 inhibitor) are considered first-line therapy.1 Vardenafil was approved by the FDA in August 2003 for erectile dysfunction. An orally disintegrating tablet was approved by the FDA in June 2010.

Tadalafil

Tadalafil is a selective phosphodiesterase (PDE) type 5 inhibitor similar to sildenafil and vardenafil. It is administered orally for the treatment of male erectile dysfunction (ED), pulmonary arterial hypertension (PAH), benign prostatic hypertrophy (BPH), or the concurrent treatment of erectile dysfunction and BPH. Tadalafil does not inhibit prostaglandins as do some agents for treating impotence (e.g., alprostadil). Unlike sildenafil, visual disturbances have not been reported with tadalafil, which is more selective for PDE5 than for PDE6 present in the retina. The duration of action of tadalafil for the treatment of ED (up to 36 hours) appears to be longer than that of sildenafil and vardenafil. Because PDE inhibitors promote erection only in the presence of sexual stimulation, the longer duration of action of tadalafil allows for more spontaneity in sexual activity. According to ED treatment guidelines, oral phosphodiesterase type 5 inhibitors (PDE5 inhibitor) are considered first-line therapy.1 Tadalafil was in phase II trials for the treatment of female sexual dysfunction, however, further investigation was discontinued. FDA approval was granted November 2003 for treatment of male erectile dysfunction (ED), and in January 2008, approval was granted for once daily use without regard to timing of sexual activity. Tadalafil (Adcirca) was FDA approved for the treatment of pulmonary arterial hypertension (PAH) in May 2009. In clinical studies of patients with pulmonary arterial hypertension (PAH), tadalafil-treated patients experienced improved exercise capacity and less clinical worsening compared to placebo. In October 2011, tadalafil received FDA approval for the treatment of the signs and symptoms of benign prostatic hyperplasia (BPH) and for the concurrent treatment of erectile dysfunction and BPH.

ED Cream

Arginine hydrochloride is a synthetic derivative of the essential amino acid L-arginine. Arginine hydrochloride may be used as an aid to the detection of growth hormone deficiency in conditions such as panhypopituitarism, pituitary dwarfism, chromophobe adenoma, postsurgical craniopharyngioma, hypophysectomy, pituitary trauma, and in problems with growth and stature. The drug has also been used in the evaluation of pituitary function in gigantism and acromegaly Further, arginine injection is used to treat high ammonia concentrations in patients with urea cycle disorders. Arginine tablets, which are dietary supplements, have been used to improve exercise capacity in patients with stable angina pectoris.1 Arginine injection was originally approved by the FDA in February 1973.