indication

Mainly used to treat patients in vasodilatory shock states such as septic shock and neurogenic shock and has shown a survival benefit over dopamine. Also used as a vasopressor medication for patients with critical hypotension.

pharmacology

Noradrenaline acts on both alpha-1 and alpha-2 adrenergic receptors to cause vasoconstriction. Its effect in-vitro is often limited to the increasing of blood pressure through antagonising alpha-1 and alpha-2 receptors and causing a resultant increase in systemic vascular resistance.

mechanism of action

Norepinephrine functions as a peripheral vasoconstrictor by acting on alpha-adrenergic receptors. It is also an inotropic stimulator of the heart and dilator of coronary arteries as a result of it's activity at the beta-adrenergic receptors.

toxicity

In high dose and especially when it is combined with other vasopressors, it can lead to limb ischemia and limb death.

drug interactions

Amitriptyline: The tricyclic antidepressant, amitriptyline, increases the sympathomimetic effect of norepinephrine.

Amoxapine: The tricyclic antidepressant, amoxapine, increases the sympathomimetic effect of norepinephrine.

Clomipramine: The tricyclic antidepressant, clomipramine, increases the sympathomimetic effect of norepinephrine.

Desipramine: The tricyclic antidepressant, desipramine, increases the sympathomimetic effect of norepinephrine.

Desvenlafaxine: Desvenlafaxine may increase the tachycardic and vasopressor effects of norepinephrine. Consider alternate therapy or monitor for increased sympathomimetic effects, such as increased blood pressure, chest pain and headache.

Doxepin: The tricyclic antidepressant, doxepin, increases the sympathomimetic effect of norepinephrine.

Entacapone: Entacapone increases the effect and toxicity of the sympathomimetic, norepinephrine.

Guanethidine: Norepinephrine may decrease the effect of guanethidine.

Imipramine: The tricyclic antidepressant, imipramine, increases the sympathomimetic effect of norepinephrine.

Isocarboxazid: Increased arterial pressure

Linezolid: Possible increase of arterial pressure

Methyldopa: Increased arterial pressure

Midodrine: Increased arterial pressure

Moclobemide: Moclobemide increases the sympathomimetic effect of norepinephrine.

Nortriptyline: The tricyclic antidepressant, nortriptyline, increases the sympathomimetic effect of norepinephrine.

Phenelzine: Increased arterial pressure

Rasagiline: Increased arterial pressure

Reserpine: Increased arterial pressure

Trimipramine: Trimipramine may increase the vasopressor effect of the direct-acting alpha-/beta-agonist, Norepinephrine. Avoid combination if possible. Monitor sympathetic response to therapy if used concomitantly.

Venlafaxine: Venlafaxine may increase the tachycardic and vasopressor effects of Norepinephrine. Consider alternate therapy or monitor for increased sympathomimetic effects, such as increased blood pressure, chest pain and headache.