Udenafil: ingredient and products

Udenafil is a PDE5 inhibitor developed in South Korea and associated with the original brand Zydena. Its exposure pattern sits between familiar shorter-acting sildenafil and longer-acting tadalafil, but pharmacokinetic timing should not be converted into a promised sexual-performance duration.

Key points

• Time to peak blood concentration and half-life describe exposure, not erection duration.
• Clinical research includes selected men taking blood-pressure medicines.
• Those findings cannot be extended to every cardiovascular condition or medicine combination.
• Zydena’s documented company-reported presence extends beyond South Korea.
• Zydena and Zudena are separate brand and company records despite their similar names.

What the time profile tells us

In a randomized early pharmacokinetic study in healthy Korean volunteers, single-dose udenafil reached peak blood concentrations at approximately 0.8–1.3 hours. Terminal half-life estimates ranged from 7.3 to 12.1 hours across the single-dose groups. The study also tested repeated dosing over seven days.

Those ranges are more informative than one exact number presented as a universal fact. The study involved healthy volunteers and several investigated amounts, including amounts not intended as general prescribing advice. Blood exposure increased more than proportionately as single doses rose. Its findings do not demonstrate that a larger printed strength buys a proportionately longer or better sexual response.

Separate research has examined daily treatment. A pharmacokinetic rationale or a daily-treatment study is not, by itself, a current daily-use authorization for every udenafil product. The applicable local leaflet still determines the product’s regimen.

The hypertension study: relevant, but selected

A 12-week randomized trial enrolled 165 men with ED receiving antihypertensive medication. Compared with placebo, both investigated udenafil groups improved erectile-function questionnaire scores: the adjusted mean changes were 8.4 and 9.8 points with 100 and 200 mg, versus 2.4 with placebo.

Headache and flushing were the most common treatment-emergent adverse events and were generally mild to moderate. Within this selected trial population, the investigators did not find an increase in adverse-event frequency or severity attributable to the studied treatment.

That is useful evidence for a clinical discussion involving treated hypertension. It is not permission to combine udenafil with every blood-pressure medicine, use it with nitrates, or overlook unstable cardiovascular disease. A short selected trial cannot settle every interaction or uncommon long-term risk.

A more accurate global picture

Dong-A ST’s international table lists Zydena among products exported to Ukraine, Malaysia and Jordan. A company announcement records a Russian launch in 2009. It is therefore inaccurate to describe all documented use as South Korea only.

These are company-reported market-presence records, with the Russian item historical. They do not replace a current national register check or establish stock today. This directory does not treat absence from a particular reference regulator as proof that a medicine has no legitimate use elsewhere.

Product and safety connections

Zydena connects the ingredient with Dong-A’s development and current company listing. Zudena is a separate Sunrise Remedies brand. A shared ingredient does not transfer a regional authorization, formulation record or trial attribution between them.

As a PDE5 inhibitor, udenafil belongs in a review of cardiovascular suitability, nitrates and other erection treatments. The trial’s headache and flushing findings are relevant tolerability information; they should not be turned into a “no side effects” claim. Use a matching local product leaflet and disclose the exact medicine during urgent assessment of chest pain or a prolonged erection.

Sources

4 sources

Checked October 4, 2026.

1. Udenafil healthy-volunteer pharmacokinetics — British Journal of Clinical Pharmacology, 2008
2. Udenafil in men receiving antihypertensive medicines — Journal of Sexual Medicine, 2009
3. International product and export table — Dong-A ST
4. Historical Russian launch announcement — Dong-A ST