EPINEPHRINE (ADRENALIN)

Therapeutic Class: Drug for anaphylaxis and shock

Pharmacologic Class: Nonselective adrenergic agonist; vasopressor

ACTIONS AND USES: Subcutaneous or IV epinephrine is a preferred drug for anaphylaxis because it can reverse many of the distressing symptoms within minutes. Epinephrine is a nonselective adrenergic agonist, stimulating both alpha- and beta-adrenergic receptors. Almost immediately after injection, BP rises due to stimulation of alpha1 receptors. Activation of beta2 receptors in the bronchi opens the airways and relieves the patient's shortness of breath. Cardiac output increases due to stimulation of beta1 receptors in the heart. In addition to the subcutaneous and IM routes, topical, inhalation, and ophthalmic preparations are available. The intracardiac route is used for cardiopulmonary resuscitation under extreme conditions, usually during open cardiac massage, or when no other route is possible.

ADMINISTRATION ALERTS: Parenteral epinephrine is an irritant that may cause tissue damage if extravasation occurs. It is Pregnancy category C.

ADVERSE EFFECTS: The most common adverse effects of epinephrine are nervousness, tremors, palpitations, tachycardia, dizziness, headache, and stinging/burning at the site of application.

When administered parenterally, hypertension and dysrhythmias may occur rapidly; therefore, the patient should be monitored carefully following injection.

CONTRAINDICATIONS: In life-threatening conditions such as anaphylaxis, there are no absolute contraindications for the use of epinephrine. The drug must be used with caution, however, in patients with dysrhythmias, cerebrovascular insufficiency, hyperthyroidism, narrow-angle glaucoma, hypertension, or coronary ischemia, because epinephrine may worsen these conditions.

INTERACTIONS: Drug–Drug: Epinephrine may result in hypotension if used with phenothiazines or oxytocin. There may be additive cardiovascular effects with other sympathomimetics. MAO inhibitors, tricyclic antidepressants, and alpha- and beta-adrenergic drugs inhibit the actions of epinephrine. Epinephrine will decrease the effects of beta blockers. Some general anesthetics may sensitize the heart to the effects of epinephrine.

RELATED;

1. BETA BLOCKERS

2. CATECHOLAMINES

3.  PHARMACOLOGY AND THERAPEUTICS

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