Not all vasopressors solve the same problem.
Norepinephrine and epinephrine both raise blood pressure, but they do so with different receptor profiles and different physiologic tradeoffs.
Norepinephrine has strong alpha-1 activity and modest beta-1 activity. It increases vascular tone, raises mean arterial pressure, and may modestly support contractility.
This makes it the default vasopressor for many forms of distributive shock.
Epinephrine has more prominent beta-1 and beta-2 effects at lower doses, with increasing alpha activity at higher doses. It can increase heart rate, contractility, cardiac output, and vascular tone.