Udenafil vs. Tadalafil

Both Udenafil (Zydena) and Tadalafil (Cialis) are drugs intended for the treatment of erectile dysfunction in men. While tadalafil is available, FDA-approved and permitted for use worldwide, udenafil is approved in South Korea (the country of origin), Russia and the Philippines. In general, udenafil is similar to tadalafil, but there are a few differences in pharmacokinetics and pharmacodynamics. Most important, udenafil has proved to be more effective in the treatment of diabetes-related ED. This also follows from udelafil vs Cialis, vardenafil, etc. comparative analyses.

Mechanism of Action

Udenafil and tadalafil are PDE-5 (phosphodiesterase type 5) inhibitors. Erection is stimulated by production and release of nitric oxide and cGMP (cyclic guanosine monophosphate) in the smooth muscle of the penis, causing it to relax and let more blood in the corpus cavernosum. As the PDE-5 enzyme blocks the production and effect of cGMP, consequently, it impedes the blood flow in the corpus cavernosum and reduces erection. These drugs block PDE-5 production and, thus, pave the way for nitric oxide and cGMP to stimulate an erection.

Although the mechanism of action is pretty much the same, udenafil demonstrates quicker absorption and onset of action. According to clinical trials, udenafil plasma level peaks within a range of 0.8 to 1.3 hours, which is faster than tadalafil. Its half-life is a little shorter than that of tadalafil, but still quite sufficient to provide a lasting effect and ensure spontaneity in a sexual relationship. This signifies that udenafil is quicker to act and clear from the body, but is hardly less effective.


Tadalafil long time side effects Udenafil can be used both as an on-demand and once-daily drug. So far, the only PDE-5 inhibitor medicine, which could boast an approval for such use, was tadalafil. However, unlike udenafil, tadalafil is PDE-5 subtype selective and therefore is not tolerated by some patients. It should be noted, however, that udenafil shows a greater PDE-11 selectivity.

Typically, doctors prescribe a 100 mg or 200 mg dose depending on the severity of dysfunction and individual physical characteristics. Tadalafil dosage is usually 10 to 20 mg. Dosage can be changed depending on effect and reaction. According to the general feedback, udenafil tablet 100 mg makes it easy for couples throughout the day. Likewise, generic tadalafil 20 mg is an optimal dose. Like any vasodilator drug, these require an examination to define whether or not it is advisable to take it.


Like any other vasodilator, udenafil should be used with caution by people suffering from hypertension, cardiac disorders, renal insufficiency, hepatic issues and allergies to any of the components contained in tablets. Co-administration with other drugs can cause issues, too. It should be noted that Udenafil is said to be ok with moderate doses of alcohol. However, in either case, one should notify his doctor prior to using tadalafil and/or udenafil in a combination with these substances.

Side Effects

They are similar for both medicines. Tadalafil long time side effects can be explained by its longer half-life and slower excretion. The most common (although unlikely) ones are the following, to name a few:

  • Visual disorders;
  • Confusion;
  • Tachycardia;
  • Dizziness;
  • Nausea;
  • Reddening of face and eyes;
  • Burning sensation in the skin.

Mild side effects usually go away shortly after the use of these drugs is started. In case they get severe and long-lasting, doctor’s consultation will be required. Most likely, the doctor will advise stopping using tadalafil or udenafil.