Medically reviewed on Jan 28, 2019
(ep i NEF rin)
- Racemic Epinephrine
- Racepinephrine HCL
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Nebulization Solution, Inhalation:
Asthmanefrin Refill: 2.25% (1 ea) [contains edetate disodium]
Nebulization Solution, Inhalation [preservative free]:
S2 (Racepinephrine): 2.25% (1 ea) [sulfite free; contains edetate disodium]
Brand Names: U.S.
- Asthmanefrin Refill [OTC]
- S2 (Racepinephrine) [OTC]
- Alpha/Beta Agonist
Stimulates alpha-, beta1-, and beta2-adrenergic receptors resulting in relaxation of smooth muscle of the bronchial tree, cardiac stimulation (increasing myocardial oxygen consumption), and dilation of skeletal muscle vasculature; small doses can cause vasodilation via beta2-vascular receptors; large doses may produce constriction of skeletal and vascular smooth muscle
Does not cross blood-brain barrier
Taken up into the adrenergic neuron and metabolized by monoamine oxidase and catechol-o-methyltransferase; circulating drug hepatically metabolized
Urine (as inactive metabolites, metanephrine, and sulfate and hydroxy derivatives of mandelic acid; small amounts as unchanged drug)
Onset of Action
Bronchodilation: Inhalation: ~1 minute
Use: Labeled Indications
Bronchospasm, relief of mild asthma symptoms: Temporary relief of mild symptoms of intermittent asthma (ie, shortness of breath, tightness of chest, wheezing). Note: Not recommended for routine management and treatment of asthma (GINA 2018; NAEPP 2007).
OTC labeling: When used for self-medication, do not use with or within 2 weeks of discontinuing an MAOI or in patients without a diagnosis of asthma.
Documentation of allergenic cross-reactivity for sympathomimetics is limited. However, because of similarities in chemical structure and/or pharmacologic actions, the possibility of cross-sensitivity cannot be ruled out with certainty.
Bronchospasm, relief of mild asthma symptoms: Note: Not recommended for routine management and treatment of asthma (GINA 2018; NAEPP 2007).
Metered-dose inhaler: Oral inhalation: 1 inhalation (0.125 mg) once; if symptoms not relieved after 1 minute, may repeat; wait ≥ 4 hours between additional doses (maximum dose: 8 inhalations/24 hours).
Nebulization solution: Hand-bulb nebulizer: 1 to 3 inhalations of 2.25% (1 vial); may repeat dose after at least 3 hours as needed (maximum dose: 12 inhalations/24 hours).
Refer to adult dosing.
Bronchospasm, relief of mild asthma symptoms: Children ≥4 years and Adolescents:
S2, Asthmanefrin (2.25% solution): Nebulization: Handheld bulb nebulizer: Add 0.5 mL (~10 drops) to nebulizer; 1 to 3 inhalations; may repeat dose after at least 3 hours if needed. Do not use more than 12 inhalations in 24 hours. Note: Not recommended for routine management and treatment of asthma (GINA 2015; NAEPP 2007).
Croup (laryngotracheobronchitis), airway edema; moderate to severe: Limited data available: Infants, Children, and Adolescents: Note: Typically relief of symptoms occurs within 10 to 30 minutes and lasts 2 to 3 hours; patients should be observed for rapid symptom recurrence and possible repeat treatment.
Racemic epinephrine (2.25% solution): Nebulization: 0.05 to 0.1 mL/kg (maximum dose: 0.5 mL) diluted in 2 to 3 mL NS, may repeat dose every 20 minutes; others have reported use of 0.5 mL as a fixed dose for all patients; use lower end of dosing range for younger infants (Hegenbarth 2008; Kliegman 2015; Rosekrans 1998; Rotta 2003; Wright 2002)
L-epinephrine (using parenteral 1 mg/mL solution): Nebulization: 0.5 mL/kg of 1:1,000 solution (maximum dose: 5 mL) diluted in NS, may repeat dose every 20 minutes; Note: Racemic epinephrine 10 mg = 5 mg L-epinephrine (Hegenbarth 2008)
Nebulization solution: Dilute in 2 to 3 mL NS in the treatment of croup (Hegenbarth 2008; Kliegman 2015; Rosekrans 1998).
For oral inhalation only.
Metered-dose inhaler: Before first use, shake inhaler then spray into the air 4 separate times. Before each inhalation, shake then spray into the air 1 time. Wash inhaler after each day by running water through the mouthpiece for 30 seconds.
Nebulization solution: For use in a hand-held rubber bulb nebulizer. Add contents of one vial (0.5 mL) of solution to nebulizer.
Avoid food or beverages that contain caffeine.
Nebulization solution: Store between 2°C to 25°C (36°F to 77°F). Protect from light and freezing; avoid excessive heat.
Metered-dose inhaler: Store between 15°C and 25°C (59°F to 77°F). Do not store near open flame or heat >49°C (120°F). Do not puncture or incinerate.
Alpha1-Blockers: May diminish the vasoconstricting effect of Alpha-/Beta-Agonists. Similarly, Alpha-/Beta-Agonists may antagonize Alpha1-Blocker vasodilation. Monitor therapy
AtoMOXetine: May enhance the hypertensive effect of Sympathomimetics. AtoMOXetine may enhance the tachycardic effect of Sympathomimetics. Monitor therapy
Beta-Blockers (Beta1 Selective): May diminish the therapeutic effect of EPINEPHrine (Oral Inhalation). Monitor therapy
Beta-Blockers (Nonselective): May enhance the hypertensive effect of EPINEPHrine (Oral Inhalation). Exceptions: Arotinolol; Carvedilol; Labetalol. Monitor therapy
Beta-Blockers (with Alpha-Blocking Properties): May diminish the therapeutic effect of EPINEPHrine (Oral Inhalation). Monitor therapy
Cannabinoid-Containing Products: May enhance the tachycardic effect of Sympathomimetics. Exceptions: Cannabidiol. Monitor therapy
Chloroprocaine: May enhance the hypertensive effect of Alpha-/Beta-Agonists. Monitor therapy
Cocaine (Topical): May enhance the hypertensive effect of Sympathomimetics. Management: Consider alternatives to use of this combination when possible. Monitor closely for substantially increased blood pressure or heart rate and for any evidence of myocardial ischemia with concurrent use. Consider therapy modification
COMT Inhibitors: May decrease the metabolism of COMT Substrates. Monitor therapy
Doxofylline: Sympathomimetics may enhance the adverse/toxic effect of Doxofylline. Monitor therapy
Ergot Derivatives: May enhance the hypertensive effect of Alpha-/Beta-Agonists. Ergot Derivatives may enhance the vasoconstricting effect of Alpha-/Beta-Agonists. Exceptions: Ergoloid Mesylates; Nicergoline. Avoid combination
Guanethidine: May enhance the arrhythmogenic effect of Sympathomimetics. Guanethidine may enhance the hypertensive effect of Sympathomimetics. Monitor therapy
Inhalational Anesthetics: May enhance the arrhythmogenic effect of EPINEPHrine (Oral Inhalation). Monitor therapy
Monoamine Oxidase Inhibitors: May enhance the hypertensive effect of EPINEPHrine (Oral Inhalation). Avoid combination
Promethazine: May diminish the therapeutic effect of EPINEPHrine (Oral Inhalation). Monitor therapy
Serotonin/Norepinephrine Reuptake Inhibitors: May enhance the tachycardic effect of Alpha-/Beta-Agonists. Serotonin/Norepinephrine Reuptake Inhibitors may enhance the vasopressor effect of Alpha-/Beta-Agonists. Consider therapy modification
Spironolactone: May diminish the vasoconstricting effect of Alpha-/Beta-Agonists. Monitor therapy
Sympathomimetics: May enhance the adverse/toxic effect of other Sympathomimetics. Monitor therapy
Tricyclic Antidepressants: May enhance the vasopressor effect of Alpha-/Beta-Agonists (Direct-Acting). Management: Avoid, if possible, the use of direct-acting alpha-/beta-agonists in patients receiving tricyclic antidepressants. If combined, monitor for evidence of increased pressor effects and consider reductions in initial dosages of the alpha-/beta-agonist. Consider therapy modification
There are no adverse reactions listed in the manufacturer's labeling.
• Cardiovascular disease: Use with caution in patients with heart disease and/or hypertension.
• Diabetes: Use with caution in patients with diabetes mellitus.
• Increased intraocular pressure/glaucoma: Use with caution in patients with increased intraocular pressure or glaucoma.
• Prostatic hyperplasia/urinary obstruction: Use with caution in patients with prostatic hyperplasia and/or GU obstruction.
• Psychiatric conditions: Use with caution in patients with psychiatric or emotional conditions.
• Seizures: Use with caution in patients with a history seizure disorder
• Thyroid disease: Use with caution in patients with thyroid disease.
Concurrent drug therapy issues:
• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.
Dosage form specific issues:
• Nebulization solution: Do not use if product is brown in color or cloudy.
• Self-medication (OTC use): When used for self-medication (OTC), notify health care provider if symptoms are not relieved in 20 minutes or become worse; if >8 inhalations of Primatene Mist, >12 inhalations of Asthmanefrin, S2 are needed in 24 hours; if >9 inhalations in 24 hours for ≥3 days a week of Asthmanefrin, S2 are needed, or if >2 asthma attacks have occurred within a week. Discontinue use and notify health care provider if your asthma is getting worse, or if difficulty sleeping, rapid heartbeat, tremors, nervousness, or seizure occur. The product should not be used more frequently or at higher doses than recommended.
FEV1, peak flow, and/or other pulmonary function tests; blood pressure, heart rate; CNS stimulation; serum glucose, serum potassium; asthma symptoms
Epinephrine crosses the placenta following injection (Sandler 1964).
Uncontrolled asthma is associated with adverse events on pregnancy (increased risk of perinatal mortality, preeclampsia, preterm birth, low birth weight infants). Poorly controlled asthma or asthma exacerbations may have a greater fetal/maternal risk than what is associated with appropriately used asthma medications (ACOG 90 2008; GINA 2018; NAEPP 2007). Epinephrine is not recommended for routine management and treatment of asthma (GINA 2018; NAEPP 2007).
• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
• Patient may experience tremors or insomnia. Have patient report immediately to prescriber signs of severe cerebrovascular disease (change in strength on one side is greater than the other, difficulty speaking or thinking, change in balance, or vision changes), angina, tachycardia, abnormal heartbeat, vision changes, passing out, anxiety, severe headache, dizziness, or seizures (HCAHPS).
• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.
Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
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