# epinephrine (medication)
![[epinephrine.svg.png]]
skeletal formula of adrenaline
![[adrenaline-from-xtal-3d-bs-17.png]]
ball-and-stick model of the zwitterionic form of adrenaline found in the crystal structure
clinical data
trade names: epipen adrenaclick others
other names: epinephrine adrenaline adrenalin; 3-4-β-trihydroxy-n-methylphenethylamine
ahfs/drugs.com: monograph
medlineplus: a603002
license data: us dailymed: epinephrine
pregnancy category: au: a -
routes of administration: intravenous intramuscular endotracheal intracardiac nasal eye drop
drug class: adrenergic receptor agonist; sympathomimetic
atc code: a01ad01 (who) b02bc09 (who) c01ca24 (who) r01aa14 (who) r03aa01 (who) s01ea01 (who)
physiological data
receptors: adrenergic receptors
metabolism: adrenergic synapse (mao and comt)
legal status
legal status: au: s4 (prescription only) - uk: pom (prescription only) - us: ℞-only - eu: rx-only
pharmacokinetic data
bioavailability: oral: negligible - intravenous: c. 99% - subcutaneous: high
protein binding: 15-20%
metabolism: adrenergic synapse (mao and comt)
metabolites: metanephrine
onset of action: rapid
elimination half-life: 2-3 minutes in plasma
duration of action: few minutes
excretion: urine
identifiers
iupac name - (r)-4-(1-hydroxy-2-(methylamino)ethyl)benzene-1-2-diol
cas number: 51-43-4 !(epinephrine%20%28medication%29/yescheck.svg.jpg|300]]
pubchem cid: 5816
iuphar/bps: 479
drugbank: db00668 !(epinephrine%20%28medication%29/yescheck.svg.jpg|300]]
chemspider: 5611 !(epinephrine%20%28medication%29/yescheck.svg.jpg|300]]
unii: ykh834o4bh
kegg: d00095 !(epinephrine%20%28medication%29/yescheck.svg.jpg|300]]
chebi: chebi:28918 !(epinephrine%20%28medication%29/yescheck.svg.jpg|300]]
chembl: chembl679 !(epinephrine%20%28medication%29/yescheck.svg.jpg|300]]
pdb ligand: ale (pdbe rcsb pdb)
chemical and physical data
formula: c9h13no3
molar mass: 183.207 g·mol−1
3d model (jsmol): interactive image
density: 1.283±0.06 g/cm3 @ 20 °c 760 torr
smiles - cnc(o)c1ccc(o)c(o)c1
inchi - inchi=1s/c9h13no3/c1-10-5-9(13)6-2-3-7(11)8(12)4-6/h2-4-9-13h-5h2-1h3/t9-/m0/s1 !(epinephrine%20%28medication%29/yescheck.svg.jpg|300]] - key:uctwmzqnuqwslp-vifpvbqesa-n !(epinephrine%20%28medication%29/yescheck.svg.jpg|300]]
epinephrine also known as adrenaline is a medication and hormone. as a medication it is used to treat several conditions including anaphylaxis cardiac arrest asthma and superficial bleeding. inhaled epinephrine may be used to improve the symptoms of croup. it may also be used for asthma when other treatments are not effective. it is given intravenously by injection into a muscle by inhalation or by injection just under the skin
common side effects include shakiness anxiety and sweating. a fast heart rate and high blood pressure may occur. occasionally it may result in an abnormal heart rhythm. while the safety of its use during pregnancy and breastfeeding is unclear the benefits to the mother must be taken into account
epinephrine is normally produced by both the adrenal glands and a small number of neurons in the brain where it acts as a neurotransmitter. it plays an essential role in the fight-or-flight response by increasing blood flow to muscles heart output pupil dilation and blood sugar. epinephrine does this through its effects on alpha and beta receptors. it is found in many animals and some single-celled organisms but the medication is produced synthetically and is not harvested from animals
jōkichi takamine first isolated epinephrine in 1901 and it came into medical use in 1905. it is on the world health organisation's list of essential medicines. it is available as a generic medication. in 2022 it was the 240th most commonly prescribed medication in the united states with more than 1 million prescriptions
the word epinephrine is formed from the ancient greek ἐπι- (epi- "on") and νεφρός (nephros "kidney") because the adrenal glands where it is produced are located just above the kidneys
![[republic of bob/citation needed (wikinovel)/attachments/epinephrine-ampule.jpg|300]]
epinephrine vial 1 mg (adrenalin)
epinephrine is used to treat a number of conditions including cardiac arrest anaphylaxis and superficial bleeding. it has been used historically for bronchospasm and low blood sugar but newer treatments for these that are selective for β2 adrenoceptors such as salbutamol are preferred
while epinephrine is often used to treat cardiac arrest it has not been shown to improve long-term survival or mental function after recovery. it does however improve return of spontaneous circulation
epinephrine is the only life-saving treatment for anaphylaxis. the commonly used epinephrine autoinjector delivers a 0.3 mg epinephrine injection (0.3 ml 1:1000.) it is indicated in the emergency treatment of allergic reactions including anaphylaxis to stings contrast agents medicines or people with a history of anaphylactic reactions to known triggers. a lower-strength product is available for children
intramuscular injection can be complicated in that the depth of subcutaneous fat varies and may result in subcutaneous injection or may be injected intravenously in error or the wrong strength used. intramuscular injection gives a faster and higher pharmacokinetic profile compared to subcutaneous injection
in august 2024 an epinephrine nasal spray (brand name neffy) was approved in the united states for the emergency treatment of allergic reactions (type i) including those that are life-threatening (anaphylaxis) in people who weigh at least 30 kilograms (66 lb.) it is the first nasal spray for the treatment of anaphylaxis approved by the us food and drug administration (fda.) in march 2025 the fda expanded the indication of neffy to include children aged four years of age and older who weigh 15 to 30 kilograms (33 to 66 lb)
the approval of epinephrine nasal spray is based on four studies in 175 healthy adults without anaphylaxis that measured the epinephrine concentrations in the blood following administration of epinephrine nasal spray or approved epinephrine injection products. results from these studies showed comparable epinephrine blood concentrations between epinephrine nasal spray and approved epinephrine injection products. epinephrine nasal spray also demonstrated similar increases in blood pressure and heart rate as epinephrine injection products two critical effects of epinephrine in the treatment of anaphylaxis. a study of epinephrine nasal spray in children weighing more than 66 pounds showed that epinephrine concentrations in children were similar to adults who received epinephrine nasal spray
the most common side effects of epinephrine nasal spray include throat irritation tingling nose (intranasal paresthesia) headache nasal discomfort feeling jittery tingling sensation (paresthesia) fatigue tremor runny nose (rhinorrhea) itchiness inside the nose (nasal pruritus) sneezing abdominal pain gum (gingival) pain numbness in the mouth (hypoesthesia oral) nasal congestion dizziness nausea and vomiting. the fda granted the application of epinephrine nasal spray fast track designation and granted the approval of neffy to ars pharmaceuticals
epinephrine is also used as a bronchodilator for asthma if specific β2 agonists are unavailable or ineffective
because of the high intrinsic efficacy (receptor binding ability) of epinephrine high drug concentrations cause adverse side effects when treating asthma. the value of using nebulised epinephrine in acute asthma is unclear
racemic epinephrine has been used for the treatment of croup. racemic adrenaline is a 1:1 mixture of the two enantiomers of adrenaline. the l-form is the active component. racemic adrenaline works by stimulating the alpha-adrenergic receptors in the airway with resultant mucosal vasoconstriction and decreased subglottic edema and by stimulating the β adrenergic receptors with resultant relaxation of the bronchial smooth muscle
there is a lack of consensus as to whether inhaled nebulised epinephrine is beneficial in the treatment of bronchiolitis with most guidelines recommending against its use
when epinephrine is mixed with local anesthetics such as bupivacaine or lidocaine and used for local anesthesia or intrathecal injection it prolongs the numbing effect and motor block effect of the anesthetic by up to an hour. epinephrine is frequently combined with local anesthetic and can cause panic attacks
epinephrine is mixed with cocaine to form moffett's solution used in nasal surgery
# # upper airway obstruction
upper airway obstruction with edema and stridor can be treated with racemic epinephrine
adverse reactions to adrenaline include palpitations tachycardia arrhythmia anxiety panic attack headache anorexia tremor hypertension and acute pulmonary edema. the use of epinephrine based eye-drops commonly used to treat glaucoma may also lead to a buildup of adrenochrome pigments in the conjunctiva iris lens and retina
rarely exposure to medically administered epinephrine may cause takotsubo cardiomyopathy
use is contraindicated in people on nonselective β-blockers because severe hypertension and even cerebral hemorrhage may result
the most common side effects of epinephrine nasal spray include throat irritation tingling nose (intranasal paresthesia) headache nasal discomfort feeling jittery tingling sensation (paresthesia) fatigue tremor runny nose (rhinorrhea) itchiness inside the nose (nasal pruritus) sneezing abdominal pain gum (gingival) pain numbness in the mouth (hypoesthesia oral) nasal congestion dizziness nausea and vomiting. the fda granted the application of epinephrine nasal spray fast track designation and granted the approval of neffy to ars pharmaceuticals
# mechanism of action
physiologic responses by organ
organ: effects
heart: increases heart rate; contractility; conduction across av node
lungs: increases respiratory rate; bronchodilation
liver: stimulates glycogenolysis
brain
systemic: vasoconstriction and vasodilation
triggers lipolysis
muscle contraction
epinephrine acts by binding to a variety of adrenergic receptors. epinephrine is a nonselective agonist of all adrenergic receptors including the major subtypes α1 α2 β1 β2 and β3. epinephrine's binding to these receptors triggers several metabolic changes. binding to α-adrenergic receptors inhibits insulin secretion by the pancreas stimulates glycogenolysis in the liver and muscle and stimulates glycolysis and inhibits insulin-mediated glycogenesis in muscle. β adrenergic receptor binding triggers glucagon secretion in the pancreas increased adrenocorticotropic hormone (acth) secretion by the pituitary gland and increased lipolysis by adipose tissue. together these effects increase blood glucose and fatty acids providing substrates for energy production within cells throughout the body. in the heart the coronary arteries have a predominance of β2 receptors which cause vasodilation of the coronary arteries in the presence of epinephrine
its actions increase peripheral resistance via α1 receptor-dependent vasoconstriction and increase cardiac output via its binding to β1 receptors. the goal of reducing peripheral circulation is to increase coronary and cerebral perfusion pressures and therefore increase oxygen exchange at the cellular level. while epinephrine does increase aortic cerebral and carotid circulation pressure it lowers carotid blood flow and end-tidal co2 or etco2 levels. it appears that epinephrine may improve macrocirculation at the expense of the capillary beds where perfusion takes place
epinephrine or adrenaline also known as 3-4-β-trihydroxy-n-methylphenethylamine is a substituted phenethylamine and catecholamine. it is the n-methylated analogue of norepinephrine (noradrenaline; 3-4-β-trihydroxyphenethylamine) and the n-methylated and β-hydroxylated analogue of dopamine (3-4-dihydroxyphenethylamine)
extracts of the adrenal gland were first obtained by polish physiologist napoleon cybulski in 1895. these extracts which ey called nadnerczyna contained adrenaline and other catecholamines. american ophthalmologist william h. bates discovered adrenaline's usage for eye surgeries prior to 20 april 1896. japanese chemist jōkichi takamine and ir assistant keizo uenaka independently discovered adrenaline in 1900. in 1901 takamine successfully isolated and purified the hormone from the adrenal glands of sheep and oxen. adrenaline was first synthesised in the laboratory by friedrich stolz and henry drysdale dakin independently in 1904
# society and culture
epinephrine is the generic name of the drug and its inntooltip international nonproprietary name and usantooltip united states adopted name while adrenaline is its bantooltip british approved name. epinephrine is sold under various brand names including asthmanefrin micronefrin neffy nephron vaponefrin and primatene mist among others
in june 2024 the committee for medicinal products for human use of the european medicines agency adopted a positive opinion recommending the granting of a marketing authorisation for the medicinal product eurneffy intended for emergency treatment of allergic reactions (anaphylaxis) due to insect stings or bites foods medicinal products and other allergens as well as idiopathic or exercise-induced anaphylaxis. the applicant for this medicinal product is ars pharmaceuticals irl limited. eurneffy was approved for medical use in the european union in august 2024
epinephrine is available in an autoinjector delivery system and a nasal spray
there is an epinephrine metered-dose inhaler sold over the counter in the united states to relieve bronchial asthma. it was introduced in 1963 by armstrong pharmaceuticals
a common concentration for epinephrine is 2.25% withv epinephrine in solution which contains 22.5 mg/ml while a 1% solution is typically used for aerosolisation
// republic of bob