epinephrine (adrenaline)

epinephrine (adrenaline)

(ep i nef' rin)

epinephrine bitartrate

Aerosols:

Primatene Mist

epinephrine borate

Ophthalmic solution:

Epinal

epinephrine hydrochloride

Injection, OTC nasal solution:

Adrenalin Chloride

Insect-sting emergencies:

EpiPen Auto-Injector (delivers 0.3 mg IM adult dose), EpiPen Jr. Auto-Injector (delivers 0.15 mg IM for children)

OTC solutions for nebulization:

AsthmaNefrin, microNefrin, Nephron, S₂

Pregnancy Category C

Drug classes

Sympathomimetic

Alpha-adrenergic agonist

Beta₁- and beta₂-adrenergic agonist

Cardiac stimulant

Vasopressor

Bronchodilator

Antasthmatic

Nasal decongestant

Mydriatic

Therapeutic actions

Naturally occurring neurotransmitter, the effects of which are mediated by alpha or beta receptors in target organs. Effects on alpha receptors include vasoconstriction, contraction of dilator muscles of iris. Effects on beta receptors include positive chronotropic and inotropic effects on the heart (beta₁ receptors);bronchodilation, vasodilation, and uterine relaxation (beta₂ receptors); decreased production of aqueous humor.

Indications

·        IV: In ventricular standstill after other measures have failed to restore circulation, given by trained personnel by intracardiac puncture and intramyocardialinjection; treatment and prophylaxis of cardiac arrest and attacks of transitory AV heart block with syncopal seizures (Stokes-Adams syndrome); syncope due to carotid sinus syndrome; acute hypersensitivity (anaphylactoid) reactions, serum sickness, urticaria, angioneurotic edema; in acute asthmatic attacks to relieve bronchospasm not controlled by inhalation or subcutaneous injection; relaxation of uterine musculature; additive to local anesthetic solutions for injection to prolong their duration of action and limit systemic absorption

·        Injection: Relief from respiratory distress of bronchial asthma, chronic bronchitis, emphysema, other COPDs

·        Aerosols and solutions for nebulization: Temporary relief from acute attacks of bronchial asthma, COPD

·        Topical nasal solution: Temporary relief from nasal and nasopharyngeal mucosal congestion due to a cold, sinusitis, hay fever, or other upper respiratory allergies; adjunctive therapy in middle ear infections by decreasing congestion around eustachian ostia

·        0.1% ophthalmic solution: Conjunctivitis, during eye surgery to control bleeding, to produce mydriasis

Contraindications and cautions

·        Contraindicated with allergy or hypersensitivity to epinephrine or components of preparation (many of the inhalant and ophthalmic products contain sulfites: Sodium bisulfite, sodium or potassium metabisulfite; check label before using any of these products in a sulfite-sensitive patient); narrow-angle glaucoma; shock other than anaphylactic shock; hypovolemia; general anesthesia with halogenated hydrocarbons or cyclopropane; organic brain damage, cerebral arteriosclerosis; cardiac dilation and coronary insufficiency; tachyarrhythmias; ischemic heart disease; hypertension; renal dysfunction (drug may initially decrease renal blood flow); COPD patients who have developed degenerative heart disease; diabetes mellitus; hyperthyroidism; lactation. Opthalmic preparations are contraindicated for those wearing contact lenses (drug may discolor the contact lens), aphakic patients (maculopathy with decreased visual acuity may occur).

·        Use cautiously with prostatic hypertrophy (may cause bladder sphincter spasm, difficult and painful urination), history of seizure disorders, psychoneurotic individuals, labor and delivery (may delay second stage of labor; can accelerate fetal heart beat; may cause fetal and maternal hypoglycemia), children (syncope has occurred when epinephrine has been given to asthmatic children).

Available forms

Solution for inhalation—1:100, 1:1,000, 1.125%, 1%; aerosol—0.35 mg, 0.5%, 0.22 mg; injection—1, 5 mg/mL; solution for injection—1:1,000, 1:2,000, 1:10,000, 1:100,000; suspension for injection—1:200; ophthalmic solution—0.1%

Dosages

ADULTS

Epinephrine injection

·        Cardiac arrest: 0.5–1 mg (5–10 mL of 1:10,000 solution) IV or by intracardiac injection into left ventricular chamber; during resuscitation, 0.5 mg q 5 min.

Intraspinal

0.2–0.4 mL of a 1:1,000 solution added to anesthetic spinal fluid mixture.

·        Other use with local anesthetic: Concentrations of 1:100,000–1:20,000 are usually used.

1:1,000 solution

·        Respiratory distress: 0.3–0.5 mL of 1:1,000 solution (0.3–0.5 mg), subcutaneously or IM, q 20 min for 4 hr.

1:200 suspension (for subcutaneous administration only)

·        Respiratory distress: 0.1–0.3 mL (0.5–1.5 mg) subcutaneously.

Inhalation (aerosol)

Begin treatment at first symptoms of bronchospasm. Individualize dosage. Wait 1–5 min between inhalations to avoid overdose.

Inhalation (nebulization)

Place 8–15 drops into the nebulizer reservoir. Place nebulizer nozzle into partially opened mouth. Patient inhales deeply while bulb is squeezed one to three times. If no relief in 5 min, give 2–3 additional inhalations. Use four to six times per day usually maintains comfort.

Topical nasal solution

Apply locally as drops or spray or with a sterile swab, as required.

Ophthalmic solution

·        Vasoconstriction, mydriasis: Instill 1–2 drops into the eye or eyes; repeat once if necessary.

PEDIATRIC PATIENTS

Epinephrine injection

·        1:1,000 solution, children and infants except premature infants and full-term newborns: 0.01 mg/kg or 0.3 mL/m² (0.01 mg/kg or 0.3 mg/m²) subcutaneously q 20 min (or more often if needed) for 4 hr. Do not exceed 0.5 mL (0.5 mg) in a single dose.

·        1:200 suspension, infants and children (1 mo–1 yr): 0.005 mL/kg (0.025 mg/kg) subcutaneously.

·        Children < 30 kg: Maximum single dose is 0.15 mL (0.75 mg). Administer subsequent doses only when necessary and not more often than q 6 hr.

Topical nasal solution

> 6 yr: Apply locally as drops or spray or with a sterile swab, as required.

Ophthalmic solutions

Safety and efficacy for use in children not established.

GERIATRIC PATIENTS OR PATIENTS WITH RENAL FAILURE

Use with caution; patients > 60 yr are more likely to develop adverse effects.

Pharmacokinetics

Route	Onset	Peak	Duration
SC	5–10 min	20 min	20–30 min
IM	5–10 min	20 min	20–30 min
IV	instant	20 min	20–30 min
Inhalation	3–5 min	20 min	1–3 hr
Eye	< 1 hr	4–8 hr	24 hr

Metabolism: Neural

Distribution: Crosses placenta; enters breast milk

Excretion: Unknown

IV facts

Preparation: 0.5 mL dose may be diluted to 10 mL with sodium chloride injection for direct injection; prepare infusion by mixing 1 mg in 250 mL D₅W (4 mcg/mL).

Infusion: Administer by direct IV injection or into the tubing of a running IV, each 1 mg over 1 min, or run infusion at 1–4 mcg/min (15–60 mL/hr).

Adverse effects

Systemic administration

·        CNS: Fear, anxiety, tenseness, restlessness, headache, light-headedness, dizziness, drowsiness, tremor, insomnia, hallucinations, psychological disturbances, seizures, CNS depression, weakness, blurred vision, ocular irritation, tearing, photophobia, symptoms of paranoid schizophrenia

·        CV: Arrhythmias, hypertension resulting in intracranial hemorrhage, CV collapse with hypotension, palpitations, tachycardia, precordial pain in patients with ischemic heart disease

·        GI: Nausea, vomiting, anorexia

·        GU: Constriction of renal blood vessels and decreased urine formation (initial parenteral administration), dysuria, vesical sphincter spasm resulting in difficult and painful urination, urinary retention in males with prostatism

·        Other: Pallor, respiratory difficulty, orofacial dystonia, sweating

Local injection

·        Local: Necrosis at sites of repeat injections (due to intense vasoconstriction)

Nasal solution

·        Local: Rebound congestion, local burning and stinging

Ophthalmic solutions

·        CNS: Headache, brow ache, blurred vision, photophobia, difficulty with night vision, pigmentary (adrenochrome) deposits in the cornea, conjunctiva, or lids with prolonged use

·        Local: Transitory stinging on initial instillation, eye pain or ache, conjunctival hyperemia

Interactions

Drug-drug

·        Increased sympathomimetic effects with other TCAs (eg, imipramine)

·        Excessive hypertension with propranolol, beta-blockers, furazolidone

·        Decreased cardiostimulating and bronchodilating effects with beta-adrenergic blockers (eg, propranolol)

·        Decreased vasopressor effects with chlorpromazine, phenothiazines

·        Decreased antihypertensive effect of guanethidine, methyldopa

Nursing considerations

Assessment

·        History: Allergy or hypersensitivity to epinephrine or components of drug preparation; narrow-angle glaucoma; shock other than anaphylactic shock;hypovolemia; general anesthesia with halogenated hydrocarbons or cyclopropane; organic brain damage, cerebral arteriosclerosis; cardiac dilation and coronary insufficiency; tachyarrhythmias; ischemic heart disease; hypertension; renal dysfunction; COPD; diabetes mellitus; hyperthyroidism; prostatichypertrophy; history of seizure disorders; psychoneuroses; labor and delivery; lactation; contact lens use, aphakic patients (ophthalmic preparations)

·        Physical: Weight; skin color, temperature, turgor; orientation, reflexes, IOP; P, BP; R, adventitious sounds; prostate palpation, normal urine output; urinalysis, renal function tests, blood and urine glucose, serum electrolytes, thyroid function tests, ECG

Interventions

·        WARNING: Use extreme caution when calculating and preparing doses; epinephrine is a very potent drug; small errors in dosage can cause serious adverse effects. Double-check pediatric dosage.

·        Use minimal doses for minimal periods of time; "epinephrine-fastness" (a form of drug tolerance) can occur with prolonged use.

·        Protect drug solutions from light, extreme heat, and freezing; do not use pink or brown solutions. Drug solutions should be clear and colorless (does not apply to suspension for injection).

·        Shake the suspension for injection well before withdrawing the dose.

·        Rotate subcutaneous injection sites to prevent necrosis; monitor injection sites frequently.

·        Keep a rapidly acting alpha-adrenergic blocker (phentolamine) or a vasodilator (a nitrate) readily available in case of excessive hypertensive reaction.

·        WARNING: Have an alpha-adrenergic blocker or facilities for intermittent positive pressure breathing readily available in case pulmonary edema occurs.

·        WARNING: Keep a beta-adrenergic blocker (propranolol; a cardioselective beta-blocker, such as atenolol, should be used in patients with respiratory distress) readily available in case cardiac arrhythmias occur.

·        Do not exceed recommended dosage of inhalation products; administer pressurized inhalation drug forms during second half of inspiration, because the airways are open wider and the aerosol distribution is more extensive. If a second inhalation is needed, administer at peak effect of previous dose, 3–5 min.

·        Use topical nasal solutions only for acute states; do not use for longer than 3–5 days, and do not exceed recommended dosage. Rebound nasal congestion can occur after vasoconstriction subsides.

Teaching points

·        Do not exceed recommended dosage; adverse effects or loss of effectiveness may result. Read the instructions that come with respiratory inhalant products, and consult your health care provider or pharmacist if you have any questions.

·        To give eye drops: Lie down or tilt head backward, and look up. Hold dropper above eye; drop medicine inside lower lid while looking up. Do not touch dropper to eye, fingers, or any surface. Release lower lid; keep eye open, and do not blink for at least 30 seconds. Apply gentle pressure with fingers to inside corner of the eye for about 1 minute; wait at least 5 minutes before using other eye drops.

·        You may experience these side effects: Dizziness, drowsiness, fatigue, apprehension (use caution if driving or performing tasks that require alertness); anxiety, emotional changes; nausea, vomiting, change in taste (eat frequent small meals); fast heart rate. Nasal solution may cause burning or stinging when first used (transient). Ophthalmic solution may cause slight stinging when first used (transient); headache or brow ache (only during the first few days).

·        Report chest pain, dizziness, insomnia, weakness, tremor or irregular heart beat (respiratory inhalant, nasal solution), difficulty breathing, productive cough, failure to respond to usual dosage (respiratory inhalant), decrease in visual acuity (ophthalmic).

Adverse effects in Italic are most common; those in Bold are life-threatening.