Tadalafil 171596-29-5 to Treat Erectile Dysfunction in Men

Tadalafil (Tadalafil, Tadalafil) has a molecular formula of C22H19N3O4 and a molecular weight of 389.4. It has been widely used in the treatment of male erectile dysfunction since 2003, with the trade name Cialis (Cialis). In June 2009, the FDA approved tadalafil in the United States for the treatment of patients with pulmonary arterial hypertension (PAH) under the trade name Adcirca. Tadalafil was introduced in 2003 as a drug for the treatment of ED. It takes effect 30 minutes after administration, but its best effect is 2h after the onset of action, and the effect can last for 36h, and its effect is not affected by food. The dose of tadalafil is 10 or 20 mg, the recommended initial dose is 10 mg, and the dose is adjusted according to the patient's response and adverse reactions. Pre-market studies have shown that after oral administration of 10 or 20 mg of tadalafil for 12 weeks, the effective rates are 67% and 81%, respectively. Many studies have shown that tadalafil has better efficacy in the treatment of ED.

Erectile Dysfunction: Tadalafil is a selective phosphodiesterase type 5 (PDE5) like sildenafil, but its structure is different from the latter, and a high-fat diet does not interfere with its absorption. Under the action of sexual stimulation, nitric oxide synthase (NOS) in penile nerve endings and vascular endothelial cells catalyzes the synthesis of nitric oxide (NO) from the substrate L-arginine. NO activates guanylate cyclase, which converts guanosine triphosphate to cyclic guanosine monophosphate (cGMP), thereby activating cyclic guanosine monophosphate-dependent protein kinase, resulting in a decrease in the concentration of calcium ions in smooth muscle cells, causing the corpus cavernosum Erection occurs due to relaxation of smooth muscle. Phosphodiesterase type 5 (PDE5) degrades cGMP into inactive products, making the penis into a weak state. Tadalafil inhibits the degradation of PDE5, leading to the accumulation of cGMP, which relaxes the smooth muscle of the corpus cavernosum, leading to penile erection. Since nitrates are NO donors, combined use with tadalafil will significantly increase the level of cGMP and lead to severe hypotension. Therefore, the combined use of the two is contraindicated in clinical practice.

Tadalafil works by inhibiting PDES. GMP is degraded, so combined use with nitrates may cause an extreme drop in blood pressure and increase the risk of syncope. CY3PA4 inducers will reduce the bioavailability of tadanafil, and the combination with rifampicin, cimetidine, erythromycin, clarithromycin, itracon, ketocon, and HVI protease inhibitors may increase the The blood concentration of the drug should be adjusted. So far, there are no reports that the pharmacokinetic parameters of this product are affected by diet and alcohol.