Cortisol AM · low result
What does a low Cortisol AM mean?
Short answer
A low morning cortisol (especially below about 3–5 mcg/dL at 8 a.m.) can indicate adrenal insufficiency — Addison's disease, pituitary disease, or suppression of the adrenal axis by glucocorticoid medication, including inhaled and topical steroids. It is the one cortisol result that should not be ignored. Values between about 5 and 15 mcg/dL are indeterminate and usually prompt an ACTH stimulation test.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
When does this result need same-day care?
- Low cortisol with vomiting, confusion, low blood pressure or collapse — emergency care (possible adrenal crisis)
What is the normal range for Cortisol AM?
- age 18+, drawn 6–10 AM: 6.20 – 19.4 mcg/dL
Can reflect adrenal insufficiency or recent steroid use.
Full reference table, citations and testing options: Cortisol AM biomarker page.
What are the common causes of low Cortisol AM?
- Glucocorticoid use — prednisone, inhaled or high-potency topical steroids, joint injections — suppressing the body's own production
- Primary adrenal insufficiency (Addison's disease, usually autoimmune)
- Secondary adrenal insufficiency from pituitary disease or after stopping long-term steroids
- Late-afternoon draw mistaken for a morning value
What symptoms go with low Cortisol AM?
- Profound fatigue, weakness
- Nausea, poor appetite, weight loss
- Dizziness on standing, salt craving
- Darkened skin creases (primary adrenal insufficiency)
What do clinicians usually check next?
- Confirm the draw time; repeat at 8 a.m. if unclear
- ACTH level and an ACTH (cosyntropin) stimulation test
- Sodium, potassium and glucose
- Review all steroid-containing medications
Follow-up tests available at TestWell: Glucose ($14.99).
How do you recheck Cortisol AM?
Prices are cash-pay; every order adds one $6 lab processing fee. Physician authorization is included; no insurance or referral needed.
| Test or panel | Type | Price | Fasting | Results |
|---|---|---|---|---|
| Men's Hormone Panel | Panel · 7 tests | $199.99 | No | 3–5 business days |
| Metabolism & Weight Loss Panel | Panel · 8 tests | $119.99 | Yes | 2–5 business days |
| Fitness & Performance Panel | Panel · 8 tests | $119.99 | Yes | 2–5 business days |
| Cortisol (AM) | Test | $26.99 | No | 2–4 business days |
Common questions
My morning cortisol was 4. What now?
That's low enough to need prompt clinical follow-up — typically an ACTH stimulation test — and a review of any steroid medications. Don't wait for a routine appointment if you feel unwell.
Sources
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.