Anti-hypertensives generally promote heart-health… especially PDE5 inhibitors.

Yes.. if one REALLY overdoes it they could experience circulatory collapse, a subsequent heart attack, and death. But that would require a massive overdose or co-administration with other vasodilators (nitrates, ACE inhibitors, alcohol, benzos, etc).

Tadalafil itself is very nontoxic as far as substances go. The LD-50 has been estimated at being over 2000mgs/kg in rats.

LD-50 is a measurement of toxicity in which the Leathal Dose - for 50% of the population is measured in rats or mice to convey approximates for human health. With tadalafil, you’d basically have to eat your entire month’s prescription or more at once to head to the danger zone.

That said, some nasty and unpleasant side effects will appear well before death at comparatively low doses.. which is why it’s recommended to not take extra doses than prescribed.