VEI Check · Cortisol Rhythm

For a body that tires easily:
cortisol rhythm testing

When you have lasting fatigue, feel you can no longer cope with stress, or wake up unrefreshed, we check the release and daily rhythm of cortisol, the stress hormone. This is often called adrenal fatigue, but that is not an official diagnosis. VEI Clinic uses evidence-based hormone tests and also looks at other causes of similar symptoms.

VEI Clinic, Gangnam — VEI Check · Cortisol Rhythm

Who It May Suit

People with lasting fatigue along with lightheadedness on standing, salt cravings or digestive discomfort
People whose sleep and stress rhythms are disrupted by shift work or caring for young children
People who bruise easily, gain weight mainly around the abdomen, or have red stretch marks or weakness in the arms and legs
People with a history of autoimmune disease or long-term steroid use
People who need to pace their activity while recovering from illness

What We Test

The specialist chooses the tests you need based on your symptoms, medications and any warning signs.

Morning (8 to 9 a.m.) blood cortisol, with ACTH when needed
When needed, a stimulation or suppression test that looks at cortisol response
Four-point salivary cortisol (in some cases): supporting information on the daily rhythm
DHEA-S (when needed)
Electrolytes (sodium and potassium), fasting glucose, HbA1c
Checks for other causes of similar symptoms: thyroid function, ferritin, vitamin B12 and folate, vitamin D, CRP, sleep and mood questionnaires, medication review

Before Your Test

Cortisol tests often need to be done between 8 and 9 a.m.
Tell us about any steroids (pills, inhalers, creams or injections), DHEA and hormonal medications, including birth control
If you take high-dose biotin, we may suggest pausing it for 48 to 72 hours
Keep to your usual caffeine and exercise routine, but avoid intense workouts just before the test
For saliva collection, avoid food and drinks (except water), brushing, flossing, gum and smoking for 30 minutes beforehand

How a Visit Works

Routine blood tests usually take 1 to 3 business days, and the daily salivary cortisol curve takes about 3 to 7 days. Stimulation and suppression tests are scheduled separately.

Consultation: we review your symptoms, sleep and work schedule, medications and supplements, and any warning signs
Test selection: we choose blood tests and, when needed, saliva tests
Testing is done by blood draw at the clinic or with a timed saliva collection kit
We explain the results and outline the next steps for your care
We then provide guidance on sleep, activity pacing, nutrition and stress management, with a referral to an endocrinology specialist when needed

Precautions

In an emergency, such as severe dehydration, collapse or a high fever with confusion, call 119 or go to an emergency room
If you are using steroids, results may be hard to interpret, so we discuss the timing of the test
If you are seriously ill with an acute condition, we test once you are stable

The VEI Clinic Approach

The purpose of this test is to confirm or rule out a true hormone disorder and to find factors that can be managed, such as thyroid function, iron, sleep and medications. Based on the results, we work with you on a realistic plan for sleep and activity pacing.

The causes of fatigue and how to manage them can vary from person to person, and the specialist decides after your consultation whether further care or medication changes are needed.

FAQ

Frequently asked questions

Can I be diagnosed with adrenal fatigue?

Adrenal fatigue is not an official diagnosis. Instead, we check cortisol release and its daily rhythm, and look at whether other causes are behind similar symptoms.

Can a saliva test alone give me an answer?

Salivary cortisol provides supporting information about your daily rhythm. When needed, it is read alongside blood tests, and the specialist interprets the results together.

I use steroid medication. Can I still be tested?

Steroids can affect the results, so we discuss test timing separately. Do not stop any medication on your own, and tell us about it at your consultation.

Do I have to come in the morning?

Blood cortisol is often measured between 8 and 9 a.m., so we recommend a morning appointment. We will let you know when you book, depending on which tests you need.