Does tadalafil improve blood flow?
Yes. Tadalafil inhibits PDE5, sustaining nitric-oxide–mediated vasodilation. This improves penile blood flow for erectile function and produces measurable improvements in pulmonary and lower-urinary-tract hemodynamics, which is why it is also used for BPH and pulmonary hypertension.
Full answer
Yes. Tadalafil inhibits phosphodiesterase type 5 (PDE5), the enzyme that breaks down cyclic GMP — the signaling molecule that mediates nitric oxide–driven smooth muscle relaxation in vascular tissue. By preserving cGMP, tadalafil sustains vasodilation in the penile arteries, improving the blood flow that supports erection. The same mechanism produces measurable hemodynamic effects beyond the penis: tadalafil is FDA-approved for benign prostatic hyperplasia (improving lower urinary tract symptoms by relaxing prostatic and bladder neck smooth muscle) and for pulmonary arterial hypertension. Daily low-dose tadalafil produces continuous effect and is the most common provider-reviewed regimen for combined ED and LUTS. PDE5 inhibitors require an existing nitric oxide signal (i.e., adequate sexual stimulation in the case of erection) — they enable, not initiate.
Educational. Not a substitute for individualized provider review.
- Tadalafil — Primary source · oMeds
- Reviewed by Dr. Laura Purdy, MD, MBA · Clinical Director, oMeds · Last reviewed 2026-05-29