Cortisol vs adrenaline: two stress hormones, two jobs

Cortisol and adrenaline are both called stress hormones, and both come from your adrenal glands. They are not the same thing. Adrenaline is the fast one that gives the jolt. Cortisol is the slower one that keeps the response going and manages energy.

Adrenaline is also called epinephrine, and noradrenaline is also called norepinephrine. Medical papers use both sets of names, so you will see them mixed.

The main differences

	Adrenaline (epinephrine)	Cortisol
Where it is made	Adrenal medulla (also noradrenaline)	Adrenal cortex
What triggers it	Nerve signals from the sympathetic nervous system	A hormone chain: hypothalamus, pituitary (ACTH), adrenal gland
Speed	Seconds	Several minutes later
How long it acts	Short-lasting effects	Longer-lasting effects
Main jobs	Fast “fight or flight” changes	Energy supply, inflammation, blood pressure, daily rhythm

The details come from a 2018 review of the stress system and a 2017 review of cortisol rhythms (Front Behav Neurosci, 2018; Endocrine Reviews, 2017).

Where each one is made

Your two adrenal glands sit on top of your kidneys. MedlinePlus says they make cortisol, aldosterone, adrenaline and noradrenaline, along with hormones the body uses to make sex hormones. So if you wondered which gland releases epinephrine and aldosterone, the answer is the adrenals, though they make them in different parts.

The 2018 review explains the split. Adrenaline and noradrenaline come from the adrenal medulla, and adrenaline makes up about 80 percent of the medulla’s catecholamine output (adrenaline plus noradrenaline). Noradrenaline also comes from nerve endings. Cortisol comes from the adrenal cortex, in response to ACTH from the pituitary gland, as the review describes. See the HPA axis.

How fast each one acts

The body handles an immediate threat with its nerve pathways first. A 2018 review calls the first phase of the stress response, driven by the sympathetic nerves and adrenal medulla, a rapid adaptation with short-lasting effects such as alertness. The slower hormonal chain that releases cortisol is called “sluggish” in comparison but produces an amplified, longer-lasting response.

A 2017 review adds that cortisol release needs new production from cholesterol, so it lags the nerve-driven release of adrenaline by several minutes.

What each one does

In the usual picture of “fight or flight”, the 2017 review describes the first line of defense as adrenaline and noradrenaline. They raise heart rate and blood pressure, improve oxygen uptake in the lungs, and release glucose and fatty acids from body stores to fuel muscles and the brain.

Cortisol then does more of the sustained work. According to the same review, it frees additional energy by promoting glucose production in the liver and by reducing insulin production in the pancreas. The review says its effect on blood vessels, which narrows them, further helps circulation and the delivery of oxygen to muscles and the brain, and that it stimulates alertness. Cortisol also acts on the immune system and inflammation, and it follows a strong daily rhythm. See what cortisol does.

How they work together

They are two parts of one system. A 2024 review notes that glucocorticoids such as cortisol help turn on the enzyme that converts noradrenaline to adrenaline in the adrenal medulla, and that cortisol helps blood vessels respond to catecholamines such as adrenaline. In cortisol deficiency, the review says there is a relative drop in adrenaline, with less blood-vessel narrowing and a lower systolic blood pressure. It lists low blood pressure as common in adrenal insufficiency, though in primary adrenal insufficiency the loss of aldosterone is a dominant factor. NIDDK lists low blood pressure that drops further on standing, with dizziness or fainting, among the symptoms. Many other conditions cause these too. See low cortisol for the signs and the emergency symptoms.

Is the “stress hormone” cortisol or adrenaline?

Both. MedlinePlus says cortisol is “sometimes called the stress hormone”, and it also lists a “fight or flight” response among the jobs of the adrenal hormones as a whole. If you want the one that surges in seconds when you are startled, that is adrenaline. If you want the one that is measured to check adrenal function, that is cortisol.

A common worry is “elevated stress hormone cortisol” on a result. A single cortisol number depends on the time of day, medicines, illness and many other things, and a single blood cortisol can’t diagnose or rule out Cushing’s syndrome or adrenal insufficiency. Take any result outside the range to a clinician. See high cortisol and when cortisol is highest.

Does a cortisol test measure adrenaline?

No. A cortisol test measures cortisol in blood, urine or saliva. Adrenaline is a separate hormone. MedlinePlus lists an inherited condition with tumors that make adrenaline and other hormones among the adrenal disorders. If a clinician suspects one, they will arrange the right tests. A cortisol test won’t answer that question.

Questions people ask

Is adrenaline the same as cortisol?

No. They come from different parts of the adrenal glands, act at different speeds and do different jobs, though they work together.

What about noradrenaline and cortisol?

Noradrenaline, also called norepinephrine, is released from the adrenal medulla and from sympathetic nerve endings. It belongs to the fast branch of the stress response, like adrenaline. The 2018 review adds that noradrenaline released in the brain also acts on the hypothalamus, which can modulate the HPA axis. The details are for researchers and are not a reason to test.

Does an adrenaline rush raise cortisol?

Stress usually activates both systems, and the review says they interact and work cooperatively or in sequence. That is a general statement about the stress system. It isn’t a guide to your own numbers.

Keep reading

• What cortisol does

  The jobs it does in stress, energy, inflammation and blood pressure.

• The HPA axis

  The hormone chain behind the slower stress response.

• What is cortisol?

  The hormone, where it comes from and why levels change.

• Cortisol and the body

  How cortisol links to sleep, stress and other systems.