Adrenaline

Products

Epinephrine is commercially available as an injection solution and as an epinephrine auto-injector from various suppliers. The active ingredient is also known as epinephrine, especially in English (in German: Epinephrin).

Structure and properties

Epinephrine (C9H13NO3, Mr = 183.2 g/mol) exists as a white, crystalline powder with a bitter taste that turns brownish on contact with air or light. Adrenaline is practically insoluble in water. It is also present in drugs as adrenaline tartrate, which dissolves readily in water. Structurally, adrenaline belongs to the catecholamines and is formed in the organism mainly in the chromaffin cells of the adrenal medulla from the amino acids phenylalanine and tyrosine. It exists as an L-enantiomer.

Effects

Epinephrine (ATC C01CA24) has sympathomimetic properties and provides energy to the organism. The effects are due to agonism at alpha and beta adrenoceptors:

  • Vasoconstriction (vasoconstriction), increase in vascular resistance.
  • Vascular dilation (vasodilation) in skeletal muscle and coronary arteries (deep doses).
  • Increase in blood pressure
  • Increase in the force of contraction (positive inotropic).
  • Increase in heart rate (positive chronotropic).
  • Relaxation of the smooth muscles of the intestine, urinary bladder (urinary retention), uterus and bronchi.
  • Bronchodilatation, increased respiration.
  • Increase in basal metabolic rate
  • Increase blood glucose levels, increase glycogenolysis and lipolysis, inhibition of insulin secretion.
  • Promotion of oxygen consumption, increased heat production.
  • Inhibition of the release of histamine and other mediators from mast cells.
  • Dilation of the pupil, lowering intraocular pressure.
  • Restlessness, anxiety, central stimulation
  • Erection of the hair

The body releases the hormone in an acute stressful situation (“fight-or-flight”), preparing for a physical activity. Adrenaline is effective as a drug for a short time. The effects occur rapidly and last for about 3 to 5 minutes. The half-life is about 3 to 10 minutes. Epinephrine is biotransformed by catechol-O-methyltransferase (COMT) and monoamine oxidase (MAO).

Indications

  • Anaphylaxis
  • Asthma
  • Pseudocroup (off-label)
  • Cardiopulmonary resuscitation (cardiovascular arrest).
  • Conversion of fine ventricular fibrillation to coarse ventricular fibrillation for improved defibrillation success.
  • As an adjunct to local anesthetics to inhibit absorption.
  • For local vasoconstriction, to stop bleeding.

Dosage

According to the professional information. Depending on the drug, subcutaneous, intramuscular, endotracheal, intravenous, inhalation, or local superficial administration is possible.

Contraindications

For complete precautions, see the drug label.

Adverse effects

The most common possible adverse effects include:

  • Tremor, headache, dizziness
  • Restlessness, anxiety
  • Rapid heartbeat, cardiac arrhythmias, hypertension, palpitations, pectanginous complaints.
  • Nausea, vomiting, dry mouth.
  • Sweating
  • Hyperglycemia