‌ 0400 663 150

Why do we use adrenaline to treat anaphylaxis?


dog balancing epipen on nose
What does adrenaline do?

Adrenaline is a naturally occurring hormone in the body that typically works to produce a fight or flight response to any perceived threats. A sudden surge of adrenaline in the system works to improve cardiac contractions and relax smooth muscles in both the airway and gastrointestinal systems. This natural response serves to prepare the body to either run away or fight back. We use a synthetic version of adrenaline called epinephrine to mimic these fight or flight mechanisms.

In anaphylactic patients, life threatening symptoms can include swelling of the airways and a sudden drop in blood pressure. By artificially activating the bodies fight or flight mechanisms we reverse the symptoms associated with life-threatening anaphylaxis. Epinephrine works by:

  1. Improving the pumping effect of the heart
  2. Opening up the airway to allow for optimal air entry
  3. Relaxing gastrointestinal movement

Improving the pump

Anaphylaxis is life- threatening for several reasons, one being the rapid and dangerous decrease in blood pressure. If blood pressure drops, our vital organs don’t receive enough oxygen to work efficiently. As this progressively worsens it has the potential to lead to complete systemic organ failure and subsequently death.

We administer adrenaline to encourage blood vessels to constrict and promote the hearts muscles to contract, together this works to improve a patients’ blood pressure. (Which is the same reason medical professionals use it in the management of patients in cardiac arrest). By making the heart beat harder and faster, blood flow improves, delivering sufficient oxygen to vital organs and tissues and assisting in the removal of waste products.

Opening up the airway

Adrenaline (epinephrine) is used to reverse bronchoconstriction, meaning it relaxes the smooth muscles in our airway to improve airflow and breathing. Swelling of the lips, face and tongue drastically reduce the ability to breath. If you notice symptoms including a hoarse/ raspy voice, wheezing or a persistent cough all of these indicate inadequate airflow.

Relaxing the Gastrointestinal system

As we mentioned earlier, adrenaline mimics the fight or flight response. If you were about to run away from danger it would be a very inconvenient time to stop for a bathroom break. So, in addition to improving blood and airflow, adrenaline (epinephrine) also works to relax the muscles in the stomach, intestines and bladder and slows down digestive processes.

The more you know!