Step I Epinephrine for anaphylaxis

[MudPhud20XX]

I get that epi is the DOC for anaphylaxis, but it will also vasodilate blood vessel (beta 2) which can worsen hypotension, right? So how do you reconcile this?
Many thanks in advance.

 

[haloschief]

It's a net pressor overall. From uptodate:

At alpha-1 receptor:
Increased vasoconstriction (at low doses)
Increased peripheral vascular resistance
Increased blood pressure
Decreased mucosal edema (eg, in larynx)
At beta-1 receptor:
Increased heart rate (chronotropy)
Increased force of cardiac contraction (inotropy)
At beta-2 receptor:
Decreased mediator release from mast cells and basophils
Increased bronchodilation
Increased vasodilation

 

[thehundredthone]

Net effects of adrenergic drugs are important. Alpha action, if present, usually predominates.