Adrenaline is a hormone produced by the adrenal glands of the kidneys. It can increase heart rate, constrict blood vessels, dilate pupils, increase sweating and breathing and inhibit digestion in the stomach and intestines.
The hormone is released in response to exercise or stress as part of the ‘fight or flight response’ to help the person fight or flee in times of danger. Energy is made available for instant use in threatening circumstances and this can prove life preserving.
However, prolonged stress can cause health problems and result in disorders such as immune system depression and infertility.
Adrenaline is also medicinal and is used in a drug formulation under the name epinephrine. Epinephrine is used in various medical situations, including:
Due to its ability to increase heart rate and blood pressure, it makes an excellent drug for regulating an irregular or arrested heart beat.