Question 1

How does tadalafil actually create an erection at the chemical level?

Accepted Answer

Tadalafil inhibits the PDE5 enzyme that normally breaks down cGMP. With more cGMP available, blood vessels in the penis relax, allowing increased blood flow that creates and maintains an erection when sexually stimulated.

Question 2

Why does tadalafil last 36 hours when other similar medications work for only 4-6 hours?

Accepted Answer

Tadalafil's unique chemical structure makes it more fat-soluble, so it stores in body tissues and dissociates slowly from the PDE5 enzyme. This extended binding time creates the prolonged 36-hour duration of action.

Question 3

How can the same medication treat both erectile dysfunction and urinary problems?

Accepted Answer

Both conditions involve smooth muscle tension. Tadalafil relaxes muscles in penile arteries for erections and simultaneously relaxes prostate and bladder muscles, improving urine flow in BPH patients.

Question 4

Why doesn't tadalafil work without sexual stimulation if it's already in your system?

Accepted Answer

Tadalafil only enhances the natural process - it doesn't initiate it. Sexual stimulation is needed to release nitric oxide that starts the chemical cascade. Tadalafil simply prolongs this natural response.

Question 5

How is tadalafil different from sildenafil (Viagra) in how they work?

Accepted Answer

Both inhibit PDE5, but tadalafil is more selective (fewer visual side effects), more fat-soluble (36-hour duration vs 4-6 hours), and effective for both ED and BPH, while sildenafil is only for ED.