(R)-4-(1-hydroxy-2-(methylamino)ethyl)benzene-1,2-diol

Epinephrine為一種作用於α及β腎上腺素接受體的交感神經致效劑。心肌收縮力強，心跳速率增加，使小支氣管動脈收縮，鬆弛子宮平滑肌，控制子宮收縮。

Metabolism
Inactivated by enzymatic transformation to metabephrine or normetanephrine; these are subsequently conjugated and excreted in the urine.

Elimination
Mostly excreted in urine as inactive metabolites; remainder excreted as unchanged drug or conjugated.

Onset
5 to 10 minutes (subcutaneous), 1 to 5 minutes (inhalation).

Duration
4 to 6 h (subcutaneous), 1 to 4 h (IM), 1 to 3 h (inhalation).

1. 使用本劑如有胸痛、不規則心跳等副作用應與醫療照應。
2. 使用本藥如有下列副作用持續或引起困擾時應與醫療照應:頭痛、神經質、不安、心臟搏動異常快速。

Alpha-adrenergic blockers (eg, phentolamine)
Vasoconstricting and hypertensive effects are antagonized.

Antihistamines
Epinephrine effects may be potentiated.

Beta-blocking agents
May decrease effects of these agents, resulting in hypertension.

Diuretics
Vascular response may be decreased.

Ergot alkaloids, phenothiazines, nitrates
Pressor effects of epinephrine may be reversed.

Furazolidone, methyldopa, Rauwolfia alkaloids
May cause hypertension.

General anesthetics (eg, halothane, cyclopropane), cardiac glycosides
The potential for the myocardium to be sensitized to the effects of sympathomimetic amines is increased. Arrhythmias may result with coadministration and may respond to beta-blockers.

Guanethidine
May increase pressor response.

Levothyroxine
Epinephrine effects may be potentiated.

Oxytoxic drugs
May cause severe persistent hypertension.

Tricyclic antidepressants
May potentiate epinephrine's vasopressive effects.

Incompatibility
Epinephrine is unstable in alkaline solutions (eg, sodium bicarbonate); avoid admixture.