Are There 2 Adrenal Glands? | A Clear Anatomy Answer

Yes, most people have two adrenal glands—one perched on top of each kidney.

You’ve got a lot going on inside your body that you never feel—until something goes off. The adrenal glands are a perfect example. They’re small, they sit deep in your upper abdomen, and they release hormones that affect things like blood pressure, salt balance, blood sugar control, and your “alert” response.

This article answers the main question right away, then walks through what the two glands do, why having a pair matters, what “normal” looks like, and what changes when someone has only one working gland. You’ll also get a plain-language rundown of common adrenal problems and the red flags that deserve fast medical care.

Two Adrenal Glands In Most People: Where They Sit And What They Do

In typical human anatomy, there are two adrenal glands. Each one sits on the upper pole of a kidney, tucked under the rib cage and behind other organs. Because of that location, you can’t feel them from the outside.

Each gland is small and shaped a bit like a cap. Despite the size, each one is built like a two-part factory with two jobs running at once:

• Adrenal cortex (outer layer): makes steroid hormones.
• Adrenal medulla (inner core): makes catecholamines, including adrenaline.

A simple way to think about the pair: your body has two glands so you have backup capacity. If one gland is removed or damaged, the other can often pick up the slack over time, depending on the condition and the hormones involved.

What Each Adrenal Gland Is Made Of

The adrenal gland has distinct regions with different hormone outputs. That division is why “adrenal hormones” isn’t one thing—it’s a group of chemicals with different roles.

Adrenal cortex: Three zones, three sets of hormones

The cortex is commonly described in three layers. Each layer has its own hormone pattern:

• Zona glomerulosa: mainly makes aldosterone, which affects sodium and potassium balance and helps regulate blood volume.
• Zona fasciculata: makes cortisol, a glucocorticoid tied to energy use, blood sugar control, and the body’s stress response.
• Zona reticularis: makes adrenal androgens such as DHEA, which can be converted into other sex hormones in the body.

Adrenal medulla: Fast-response chemistry

The medulla produces epinephrine (adrenaline) and norepinephrine (noradrenaline). These are part of the “fight-or-flight” response, raising alertness and shifting blood flow patterns for short bursts of demand.

Why Two Glands Matter In Real Life

The two adrenal glands aren’t “left does X, right does Y.” They do the same core jobs, but having a pair gives your body resilience.

Redundancy and reserve capacity

If one adrenal gland is removed (such as for a tumor that’s not cancer) or damaged, the remaining gland can often enlarge a bit and increase output. That compensation can take time. Some people need temporary steroid replacement after surgery, and some don’t, depending on the reason for removal and whether the other gland is healthy.

Paired anatomy is common in endocrine organs

Humans have a mix of single and paired hormone-producing organs. The thyroid is single. The adrenal glands are paired. The ovaries and testes are paired. The “pair” setup doesn’t guarantee protection from disease, but it can help when one side is lost.

When Someone Does Not Have Two Working Adrenal Glands

Two glands is the usual setup, yet real bodies vary. People can end up with one working gland for several reasons:

• Surgical removal of one gland (adrenalectomy).
• Damage from bleeding, infection, or tumors.
• Congenital differences, where one gland never formed (rare).
• Loss of function from autoimmune disease or other causes of adrenal insufficiency.

There’s another wrinkle: a person can have two glands present yet still lack normal hormone output. That’s why “Do you have two glands?” and “Do they work?” are different questions.

Accessory adrenal tissue and adrenal “rests”

Some people have small islands of adrenal-like tissue outside the main glands. These are often called adrenal rests. Many never cause symptoms, and many are found only by imaging or surgery for something else. When hormone issues are present, clinicians interpret imaging in the full clinical context rather than assuming every little nodule is the main problem.

How Doctors Confirm Adrenal Anatomy And Function

When adrenal questions come up, clinicians usually start with symptoms and bloodwork, then use imaging when needed. Imaging can show whether there are two glands present and whether either looks enlarged or has a mass. Testing can show whether hormone output matches what the body needs.

Imaging used to view adrenal glands

• CT scan: commonly used to see adrenal size, shape, and nodules.
• MRI: used when more detail is needed for certain tissue patterns.
• Ultrasound: less useful for adult adrenal glands due to their deep position, though it can help in newborns.

Hormone tests used to check output

Testing depends on the concern. It may include cortisol levels, ACTH, aldosterone and renin, and catecholamine markers. Many of these tests are time-sensitive or need special handling, so clinicians follow lab instructions closely.

For a plain-language overview of where the glands sit and what they produce, see the MedlinePlus adrenal glands encyclopedia entry.

Hormone Or Hormone Group	Made In	Main Roles In The Body
Cortisol	Adrenal cortex (zona fasciculata)	Energy use, blood sugar control, stress response regulation
Aldosterone	Adrenal cortex (zona glomerulosa)	Sodium retention, potassium excretion, blood volume control
DHEA	Adrenal cortex (zona reticularis)	Precursor for sex hormones; varies by age and sex
Other adrenal androgens	Adrenal cortex (zona reticularis)	Contribute to androgen pool; effects depend on overall hormone balance
Epinephrine (adrenaline)	Adrenal medulla	Short-burst alert response, heart rate and blood flow changes
Norepinephrine (noradrenaline)	Adrenal medulla	Vessel tone changes, alert response signaling
Steroid hormone families	Adrenal cortex (multiple zones)	Group term for glucocorticoids, mineralocorticoids, and androgens
Catecholamine family	Adrenal medulla	Group term for adrenaline-type hormones used in fast responses

Are There Two Adrenal Glands In Everyone? What Variations Mean

For most people, yes: there are two adrenal glands. Still, medicine runs into edge cases. A person might have:

• Two glands that look normal and work normally.
• Two glands present, with reduced output from one or both.
• Only one gland present after surgery or injury.
• Only one gland formed before birth (rare).

When the body has one working adrenal gland, the big question becomes function: is the remaining gland making enough hormones for daily life and for stressful events like infection, surgery, or trauma? That’s where testing and careful follow-up matter.

A readable medical overview of the glands and their hormone outputs is also available through the Cleveland Clinic adrenal gland overview.

Living With One Adrenal Gland: What Usually Changes

Plenty of people live with one adrenal gland and do fine. The outcome depends on why one gland is missing or not working, and whether the remaining gland is healthy.

After one-gland removal

If one gland is removed and the other is normal, the remaining gland often increases output over time. Some people need steroid medicine for a short period after surgery. Others don’t. The care plan is shaped by lab results and symptoms, not only by anatomy.

If output is low

When cortisol output is too low, symptoms can include fatigue, weight loss, nausea, dizziness when standing, and low blood pressure. When aldosterone output is low, salt balance can swing, and potassium can rise. Those patterns require medical assessment and a plan for steroid replacement when needed.

For a government health overview of adrenal insufficiency and Addison’s disease, the NIDDK adrenal insufficiency page lays out definitions, symptoms, and treatment approaches.

Common Adrenal Problems That Lead To Testing

Most people never think about their adrenal glands. Testing often starts after symptoms raise suspicion or imaging finds an adrenal nodule incidentally.

Adrenal insufficiency

Adrenal insufficiency means the body isn’t making enough adrenal hormones, most notably cortisol. It can be primary (the adrenal glands themselves are the source) or secondary/tertiary (a signaling problem from higher up in the hormone chain). Treatment often includes steroid replacement and a “sick day” plan for times of illness.

Excess cortisol production (Cushing syndrome)

Too much cortisol over time can lead to weight gain in the trunk, muscle weakness, skin changes, and blood sugar issues. Causes vary, and diagnosis is specialized.

Primary aldosteronism

Overproduction of aldosterone can cause high blood pressure and low potassium. Diagnosis uses blood tests and sometimes more specialized studies.

Pheochromocytoma and related tumors

Some tumors of adrenal medulla tissue can overproduce catecholamines, causing episodes of pounding heart, sweating, headaches, and blood pressure spikes. These conditions require careful testing and management.

For a patient-focused summary that states the body has two adrenal glands and describes the cortex and medulla, see the Merck Manual overview of the adrenal glands.

Situation	What It Can Mean	Common Next Steps
One adrenal gland removed	Remaining gland may increase output over time	Post-op labs, symptom tracking, short-term steroids in some cases
Two glands present, low cortisol output	Adrenal insufficiency (primary or signaling-related)	Cortisol/ACTH testing, treatment plan, sick-day instructions
Adrenal nodule found on imaging	Often benign, sometimes hormone-producing	Hormone screening, imaging follow-up based on size and features
High blood pressure with low potassium	Aldosterone excess is one possible cause	Aldosterone/renin testing, directed evaluation if confirmed
Episodes of sweating, pounding heart, headaches	Catecholamine excess can fit this pattern	Urine or blood markers, imaging once labs suggest the diagnosis
Unexplained fatigue with dizziness on standing	Low cortisol or low aldosterone can contribute	Medical evaluation, blood pressure checks, targeted labs

Red Flags That Need Fast Medical Care

Some adrenal problems can escalate quickly. Seek urgent medical care if any of the following happen, especially if adrenal insufficiency is known or suspected:

• Severe weakness with fainting or near-fainting
• Confusion, severe drowsiness, or inability to stay awake
• Persistent vomiting that prevents taking medicines or fluids
• Severe abdominal pain with low blood pressure signs

If adrenal insufficiency is already diagnosed, clinicians often give clear instructions on emergency steroids and when to head to the ER. Follow that plan exactly. If no plan exists yet and symptoms are severe, urgent evaluation is the safe move.

A Simple Way To Remember What The Adrenal Pair Does

If you want a quick mental model without medical jargon, think in three buckets:

• Salt and water control (aldosterone): ties into blood volume and blood pressure.
• Fuel management (cortisol): helps regulate glucose availability and stress responses.
• Fast alert response (adrenaline-type hormones): short bursts of action when needed.

Both glands run these jobs. Two glands gives you a pair of production sites. When one site is lost, the other may compensate, yet that’s not guaranteed in every condition. That’s why symptoms and lab results guide decisions.

Quick Self-Check: Questions To Bring To An Appointment

If you’re reading this because imaging mentioned an adrenal gland or your clinician raised the topic, these questions can keep the visit focused:

• Do my test results point to underproduction, overproduction, or a normal pattern?
• If a nodule was seen, does its size or appearance change the follow-up plan?
• Do I need screening labs for cortisol, aldosterone, or catecholamine markers?
• If one gland is removed or not working, do I need a temporary steroid plan?
• What symptoms should trigger urgent care?

That list won’t replace medical advice, yet it can help you leave the visit with clear next steps and fewer loose ends.