epINEPHrine

epinephrine /epi·neph·rine/ (-nef´rin) a catecholamine hormone secreted by the adrenal medulla and a central nervous system neurotransmitter released by some neurons. It is stored in chromaffin granules and is released in response to hypoglycemia, stress, and other factors. It is a potent stimulator of the sympathetic nervous system (adrenergic receptors), and a powerful vasopressor, increasing blood pressure, stimulating the heart muscle, accelerating the heart rate, and increasing cardiac output. It is used as a topical vasoconstrictor, cardiac stimulant, systemic antiallergic, bronchodilator, and topical antiglaucoma agent; for the last two uses it is also administered as the bitartrate salt. Called also adrenaline (Great Britain).

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ep·i·neph·rine or ep·i·neph·rin (p-nfrn)

n.

1. A catecholamine hormone of the adrenal medulla that is the most potent stimulant of the sympathetic nervous system, resulting in increased heart rate and force of contraction, vasoconstriction or vasodilation, relaxation of bronchiolar and intestinal smooth muscle, glycogenolysis, lipolysis, and other metabolic effects. Also called adrenaline.

2. A white to brownish crystalline compound isolated from the adrenal glands of certain mammals or synthesized and used in medicine as a heart stimulant, vasoconstrictor, and bronchial relaxant.

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Epinephrine

Also called adrenalin, a secretion of the adrenal glands (along with norepinephrine) that helps the liver release glucose and limits the release of insulin. Norepinephrine is both a hormone and a neurotransmitter, a substance that transmits nerve signals.

Mentioned in: Adrenal Gland Cancer, Catecholamines Tests, Hypoglycemia, Liposuction, Smoking

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epINEPHrine

[ep′ənef′rin]

Etymology: Gk, epi + nephros, kidney

an endogenous adrenal hormone and synthetic adrenergic agent. It acts as an agonist at alpha-1, alpha-2, beta-1, and beta-2 receptors. Also called adrenaline.

indications It is prescribed to treat anaphylaxis, acute bronchial spasm, and nasal congestion and to increase the effectiveness of a local anesthetic.

contraindication Known hypersensitivity to this drug prohibits its use.

adverse effects Among the most serious adverse effects are arrhythmias, increases in blood pressure, rebound congestion (when it is used as a decongestant), tachycardia, and nervousness.

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epinephrine (eh·pi·neˑ·frin),

n neurochemical produced by the adrenal glands that arouses the sympathetic response. Also called
adrenaline.

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epinephrine (ep´inef´rin),

n a hormone secreted by the adrenal medulla that stimulates hepatic glycogenolysis, causing an elevation in the blood sugar, vasodilation of blood vessels of the skeletal muscles, vasoconstriction of the arterioles of the skin and mucous membranes, relaxation of bronchiolar smooth muscles, and stimulation of heart action. Used in local anesthetics for its vasoconstrictive action to prolong the anesthesia action, provide hemostasis, and reduce systemic complications.

epinephrine/epinephrine bitartrate/epinephrine HCl,

n brand names: EpiPen Jr., Bronkaid Mist, Primatene Mist;
drug class: adrenergic agonist, catecholamine;
action: β1- and β2-agonist, causing increased levels of cAMP, producing bronchodilation and cardiac stimulation;
uses: acute asthmatic attacks, hemostasis, bronchospasm, anaphylaxis, allergic reactions, cardiac arrest, vasopressor. Recommended for the dental office or clinic emergency kit. See EpiPen.

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epinephrine

a hormone produced by the medulla of the adrenal glands; called also adrenaline. Its function is to aid in the regulation of the sympathetic branch of the autonomic nervous system. At times when an animal is highly stimulated, as by fear, anger or some challenging situation, extra amounts of epinephrine are released into the bloodstream, preparing the body for energetic action. Epinephrine is a powerful vasopressor which increases blood pressure and increases the heart rate and cardiac output. It also increases glycogenolysis and the release of glucose from the liver.

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adrenaline (epinephrine) 

A hormone of the adrenal medulla which, instilled in the eye, causes a constriction of the conjunctival vessels, dilates the pupil and diminishes the intraocular pressure. See adrenergic receptors; ocular decongestant; naphazoline; neurotransmitter; noradrenaline (norepinephrine).

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epinephrine Warning - High-alert drug!

Bronkaid Mistometer (CA), Primatene Mist, Twinject

Pharmacologic class: Sympathomimetic (direct acting)

Therapeutic class: Bronchodilator, mydriatic

Pregnancy risk category C

Action

Stimulates alpha- and beta-adrenergic receptors, causing relaxation of cardiac and bronchial smooth muscle and dilation of skeletal muscles. Also decreases aqueous humor production, increases aqueous outflow, and dilates pupils by contracting dilator muscle.

Availability

Aerosol inhaler: 160 mcg, 200 mcg, 220 mcg, 250 mcg

Auto-injector for I.M. injection: 1:2,000 (0.5 mg/ml)

Injection: 0.01 mg/ml, 0.1 mg/ml, 0.5 mg/ml, 1 mg/ml, 5 mg/ml parenteral suspension

Nebulizer inhaler: 1%, 1.25%, 2.25%

Ophthalmic drops: 0.5%, 1%, 2%

Solution: 1:200,000

⊘Indications and dosages

➣ Bronchodilation; anaphylaxis; hypersensitivity reaction

Adults: 0.1 to 0.5 ml of 1:1,000 solution subcutaneously or I.M., repeated q 10 to 15 minutes p.r.n. Or 0.1 to 0.25 ml of 1:10,000 solution I.V. slowly over 5 to 10 minutes; may repeat q 5 to 15 minutes p.r.n. or follow with a continuous infusion of 1 mcg/minute, increased to 4 mcg/minute p.r.n. For emergency treatment, EpiPen delivers 0.3 mg I.M. of 1:1,000 epinephrine.

Children: For emergency treatment, EpiPen Jr. delivers 0.15 mg I.M. of 1:2,000 epinephrine.

➣ Acute asthma attack

Adults and children ages 4 and older: 160 to 250 mcg metered aerosol (equivalent to one inhalation); repeat once after 1 minute, if needed. Don't give subsequent doses for at least 3 hours. Or one to three deep inhalations of 1% solution with hand-held nebulizer, repeated q 3 hours p.r.n.

➣ To restore cardiac rhythm in cardiac arrest

Adults: 0.5 to 1 mg I.V., repeated q 3 to 5 minutes, if needed. If no response, may give 3 to 5 mg I.V. q 3 to 5 minutes.

➣ Chronic simple glaucoma

Adults: One drop in affected eye once or twice daily. Adjust dosage to meet patient's needs.

➣ To prolong local anesthetic effects

Adults and children: 1:200,000 concentration with local anesthetic

Contraindications

• Hypersensitivity to drug, its components, or sulfites
• Angle-closure glaucoma
• Cardiac disease
• Cerebral arteriosclerosis
• MAO inhibitor use within past 14 days
• Labor
• Breastfeeding

Precautions

Use cautiously in:
• hypertension, hyperthyroidism, diabetes, prostatic hypertrophy
• elderly patients
• pregnant patients
• children.

Administration

• In anaphylaxis, use I.M. route, not subcutaneous route, if possible.
☞ Inject EpiPen and EpiPen Jr. only into anterolateral aspect of thigh. Don't inject into buttocks or give I.V.
☞ Be aware that not all epinephrine solutions can be given I.V. Check manufacturer's label.
• For I.V. injection, give each 1-mg dose over at least 1 minute. For continuous infusion, use rate of 1 to 10 mcg/minute, adjusting to desired response.
• Use Epi-Pen Jr. for patients weighing less than 30 kg (66 lb).
☞ Don't give within 14 days of MAO inhibitors.

Route	Onset	Peak	Duration
I.V.	Immediate	5 min	Short
I.M.	Variable	Unknown	1-4 hr
Subcut.	5-15 min	0.5 hr	1-4 hr
Inhalation	1-5 min	Unknown	1-3 hr

Adverse reactions

CNS: nervousness, anxiety, tremor, vertigo, headache, disorientation, agitation, drowsiness, fear, dizziness, asthenia, cerebral hemorrhage, cerebrovascular accident (CVA)

CV: palpitations, widened pulse pressure, hypertension, tachycardia, angina, ECG changes, ventricular fibrillation, shock

GI: nausea, vomiting

GU: decreased urinary output, urinary retention, dysuria

Respiratory: dyspnea, pulmonary edema

Skin: urticaria, pallor, diaphoresis, necrosis

Other: hemorrhage at injection site

Interactions

Drug-drug. Alpha-adrenergic blockers: hypotension from unopposed beta-adrenergic effects

Antihistamines, thyroid hormone, tricyclic antidepressants: severe sympathomimetic effects

Beta-adrenergic blockers (such as propranolol): vasodilation and reflex tachycardia

Cardiac glycosides, general anesthetics: increased risk of ventricular arrhythmias

Diuretics: decreased vascular response

Doxapram, mazindol, methylphenidate: enhanced CNS stimulation or pressor effects

Ergot alkaloids: decreased vasoconstriction

Guanadrel, guanethidine: enhanced pressor effects of epinephrine

Levodopa: increased risk of arrhythmias

Levothyroxine: potentiation of epinephrine effects

MAO inhibitors: increased risk of hypertensive crisis

Drug-diagnostic tests. Glucose: transient elevation

Lactic acid: elevated level (with prolonged use)

Patient monitoring

☞ Monitor vital signs, ECG, and cardiovascular and respiratory status. Watch for ventricular fibrillation, tachycardia, arrhythmias, and signs and symptoms of shock. Ask patient about anginal pain.
• Assess drug's effect on underlying problem (such as anaphylaxis or asthma attack), and repeat dose as needed.
☞ Monitor neurologic status, particularly for decreased level of consciousness and other signs and symptoms of cerebral hemorrhage or CVA.
• Monitor fluid intake and output, watching for urinary retention or decreased urinary output.
• Inspect injection site for hemorrhage or skin necrosis.

Patient teaching

• Teach patient who uses auto-injector how to use syringe correctly, when to inject drug, and when to repeat doses.
• Teach patient who uses hand-held nebulizer correct use of equipment and drug. Explain indications for both initial dose and repeat doses.
☞ Inform patient that drug may cause serious adverse effects. Tell him which symptoms to report.
• If patient will self-administer drug outside of health care setting, explain need for prompt evaluation by a health care provider to ensure that underlying disorder has been corrected.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.

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epinephrine

Physiology A sympathomimetic catecholamine hormone synthesized in the adrenal medulla and released into the circulation in response to hypoglycemia and sympathetic nervous system–splanchnic nerve stimulation due to exercise and stress; it acts on α– and β-receptors, resulting in vasoconstriction or vasodilation, ↓ peripheral blood flow, ↑ heart rate, ↑ force of contractility, ↑ glycogenolysis, ↑ lipolysis; pharmacologic epinephrine is used as bronchodilator for acute asthma to ↑ BP and in acute MIs to improve myocardial and cerebral blood flow. See Fight-or-flight response, High-dose epinephrine.