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Tadalafil

Clinical evidence
Sexual health

The long-acting erection pill that also treats enlarged prostate and a form of high blood pressure in the lungs.

What it is

Tadalafil is the drug sold as Cialis. It is a small molecule, not a peptide, but it appears on this board because vendors stock it beside peptides. It relaxes the muscle in blood-vessel walls so more blood flows through. Its signature feature is duration: a single dose can last about a day and a half.

How it works

The molecule blocks an enzyme called PDE5 that otherwise breaks down a vessel-relaxing messenger. By keeping that messenger around, tadalafil keeps vessels open longer. One simple action explains why a single drug treats erectile dysfunction, benign prostate enlargement, and a rare lung condition.

What people report

  • Large effect on erectile function: 75% of attempts completed at the top dose in pooled trials
  • Lasts up to 36 hours, far longer than its main competitor
  • A low daily dose helps both erectile function and urinary symptoms at once
  • Approved for decades with a deep safety record and cheap generics

Typical use

Used on demand before activity or as a low daily dose for continuous effect, depending on the goal.

Dosing reference

Approved doses range from 2.5 to 20 mg depending on use. It is a prescription drug; obtain it through proper channels and follow a clinician's guidance.

Reference only — not a recommendation. Verify via primary sources.

Watch for

It is well proven within its approved uses. Some outside claims are thinner: lung or brain benefits come from more limited evidence, and one Duchenne muscular-dystrophy trial missed its goals.

Educational content — not medical advice.