Latest research on Cialis

Tadalafil is an orally adminstered drug used to treat male erectile dysfunction (impotence). It is marketed worldwide under the brand name Cialis. It is a phosphodiesterase 5 (PDE5) inhibitor. Tadalafil's distinguishing pharmacologic feature is its longer half-life (17.5 hours) compared with Viagra and Levitra (4-5 hours). This longer half-life results in a longer duration of action and is, in part, responsible for the Cialis nickname of the "weekend pill." This longer half-life also is the basis of current investigation for tadalafil's use in pulmonary arterial hypertension as a once-daily therapy. [Wikipedia]

Cialis side effects

Now introduced in 50 countries with multiple PDE5i formulations (tadalafil or Cialis, vardenafil or Levitra), patents expiring globally, and investigations for off-label use, such as in cardiovascular disease [4] or altitude sickness [5], [6], we may not only see an increase in the amount of PDE5i prescribed but also more long-term side effects surfacing as a result. [source, 2013]
Since normal erection needs a high level concentration of cyclic GMP to decrease calcium ions in vascular smooth muscle cells of the penis, thus, the inhibitors of PDE5 were used for treating erectile dysfunction such as sildenafil citrate (Viagra) and tadalafil (Cialis) [source, 2009]