Why must the DHEA unconjugated test be collected in the morning?

Unconjugated DHEA follows a diurnal rhythm — peaking at approximately 08:00 hours and declining by 50–80% through the day, closely paralleling the cortisol diurnal pattern. All reference ranges for unconjugated DHEA are calibrated to morning collection between 08:00 and 09:00 hours. Specimens collected outside this window will produce systematically lower results that cannot be compared to standard reference ranges and may produce spuriously abnormal or falsely reassuring interpretations.

When is DHEA unconjugated the appropriate test over DHEA-S?

Unconjugated DHEA is specifically indicated for: concurrent morning adrenal assessment alongside cortisol where the real-time secretory fraction is required; monitoring oral DHEA supplementation where the active unconjugated species is the supplemented form; characterising the cortisol:DHEA ratio in HPA axis dysregulation evaluation; and investigating acute adrenal androgen secretory activity in CAH or adrenal tumour workup. In most other clinical contexts, DHEA-S is the analytically superior and practically more reliable first-line choice.

Can oral DHEA supplementation affect the unconjugated DHEA result?

Yes — substantially. Oral DHEA supplementation raises both unconjugated DHEA and DHEA-S, with unconjugated DHEA rising sharply within 1–2 hours of dosing and declining rapidly relative to DHEA-S. Practitioners monitoring DHEA supplementation must document the dose and timing of the most recent dose relative to specimen collection. Trough (pre-dose) and peak (1–2 hours post-dose) collections serve different interpretive purposes and should not be compared as equivalent measurements.

What does a low unconjugated DHEA result indicate?

Low unconjugated DHEA below the age-stratified reference limit indicates reduced adrenal zona reticularis output. In younger patients, primary adrenal insufficiency, hypopituitarism, or HPA axis suppression from exogenous glucocorticoids are the primary differentials, requiring concurrent assessment of morning cortisol and ACTH. In older patients, low DHEA is an expected feature of adrenal ageing — adrenopause — and in functional medicine guides DHEA supplementation decisions. Low DHEA with elevated or high-normal cortisol (elevated cortisol:DHEA ratio) is the HPA dysregulation pattern associated with chronic stress in functional endocrinology practice.

Does fasting affect the DHEA unconjugated test result?

Fasting status has a minor effect on unconjugated DHEA. Collection timing — 08:00 to 09:00 hours — is the dominant pre-analytical requirement and far more critical than fasting status. A light overnight fast is acceptable and preferable if morning cortisol is being measured concurrently. Water is always permitted. Strenuous exercise, significant psychological stress, or acute illness on the morning of collection will affect results more meaningfully than fasting status.

How long does it take to receive DHEA unconjugated results from Quest Diagnostics?

Results are typically available within 2–4 business days from specimen receipt at the Quest Diagnostics processing laboratory.

What conditions cause elevated unconjugated DHEA?

Elevated unconjugated DHEA can indicate adrenal zona reticularis excess driven by insulin resistance or ACTH hyperstimulation, congenital adrenal hyperplasia (particularly 21-hydroxylase deficiency — confirm with 17-hydroxyprogesterone), adrenal androgen-secreting tumour (markedly elevated values with rapid virilisation onset), or exogenous DHEA supplementation. In women with PCOS, mildly elevated DHEA alongside elevated testosterone reflects adrenal androgen contribution to the PCOS androgen excess pattern. Values more than three times the upper reference limit warrant adrenal imaging to exclude adrenal tumour.

BML-ADR-001adrenal stressUSA

DHEA, Unconjugated (Dehydroepiandrosterone)

The DHEA Unconjugated test measures the biologically active, unsulfated form of dehydroepiandrosterone in serum — the rapidly fluctuating adrenal androgen precursor fraction distinct from the sulfated storage form DHEA-S. It requires standardised morning collection between 08:00 and 09:00 hours due to its pronounced diurnal variation and is specifically indicated for real-time adrenal secretory…

Biomarkers

Blood (serum)

Sample

2–4 business days

Turnaround

No — however, collection must occur between 08:00 and 09:00 hours to align with the morning DHEA peak and ensure results are interpretable against morning-calibrated reference ranges. This timing requirement supersedes fasting status as the most critical pre-analytical instruction for this analyte. Light fasting (overnight fast) is acceptable and preferred if cortisol is being measured concurrently; water is always permitted.

Fasting

What is the DHEA Unconjugated test?

The DHEA Unconjugated test measures the immediate, biologically active form of dehydroepiandrosterone in serum — the free, unsulfated fraction that acts directly as a precursor to active androgens and oestrogens in peripheral tissues and that reflects the rapidly fluctuating adrenal DHEA secretory rate at the time of collection. It is ordered when the clinical question specifically concerns the bioavailable DHEA fraction and its diurnal secretory pattern, rather than the integrated long-term adrenal androgen reserve captured by DHEA-S. Specific clinical indications include the investigation of adrenal androgen excess (congenital adrenal hyperplasia, adrenal tumour, PCOS with adrenal androgen contribution), adrenal androgen insufficiency (Addison's disease, HPA axis suppression, adrenal ageing), and monitoring DHEA supplementation in patients receiving bioidentical DHEA as part of a hormone replacement or adrenal support protocol — where unconjugated DHEA reflects the supplemented active fraction more directly than DHEA-S in some dosing contexts. The choice between unconjugated DHEA and DHEA-S is a clinically meaningful one that practitioners ordering this test should be deliberate about. DHEA-S is the standard of care in mainstream endocrinology for adrenal androgen assessment due to its substantially greater pre-analytical stability, negligible diurnal variation, and lack of acute-phase sensitivity — attributes that make a single random-timing blood draw clinically reliable. Unconjugated DHEA, by contrast, must be collected at a standardised morning time point (08:00–09:00 hours) to be interpretable, is sensitive to physical and psychological stress at the time of collection, and shows substantially greater intra-individual variability. Unconjugated DHEA is the more appropriate marker when real-time adrenal secretory activity is the clinical focus — for example, acute assessment of adrenal function alongside morning cortisol — or when monitoring oral DHEA supplementation where the unconjugated form is the directly supplemented species.

What does the DHEA Unconjugated test measure?

DHEA(Dehydroepiandrosterone, Unconjugated (Free DHEA))

Range: Male: 180–1250 ng/dL (6.24–43.3 nmol/L); Female: 130–980 ng/dL (4.50–33.9 nmol/L) # REVIEWER FLAG: Confirm Quest Diagnostics sex-specific and age-stratified reference ranges for unconjugated DHEA — values decline substantially with age and reference intervals are typically reported in age-stratified tiers. The ranges above are broad adult approximations; confirm Quest Diagnostics' age-band breakdown (e.g., 18–29, 30–39, 40–49, 50–59, 60+) and update accordingly. Also confirm whether Quest reports in ng/dL or uses a different primary unit for this analyte.Optimal: Age-adjusted upper tertile of the reference range is the functional medicine target — integrative practitioners typically target levels equivalent to a patient's values at age 25–35 as a personalised anti-ageing reference point. Specific numerical targets depend on the patient's age-stratified reference range. # REVIEWER FLAG: Optimal range for unconjugated DHEA is not standardised across functional medicine literature — reviewer to confirm whether a specific functional optimal range should be cited or whether an age-relative framing is preferable.ng/dL / nmol/L

Dehydroepiandrosterone (DHEA) is a C19 adrenal androgen precursor steroid produced predominantly by the zona reticularis of the adrenal cortex, with minor contributions from the gonads and peripheral tissues via local steroidogenesis. Unlike its sulfated counterpart DHEA-S, unconjugated DHEA has a short plasma half-life of approximately 1–3 hours and exhibits pronounced diurnal variation — peaking in the early morning (approximately 08:00 hours) and declining by 50–80% by the late afternoon and evening, following the cortisol diurnal rhythm. DHEA is the precursor substrate for peripheral conversion to testosterone, estradiol, and other active androgens and oestrogens via tissue-specific steroidogenic enzymes expressed in liver, adipose, skin, adrenal, and gonadal tissues. It circulates both free and bound to albumin; approximately 90% is rapidly sulfated to DHEA-S by SULT2A1 in the adrenal gland and liver, making DHEA-S the dominant circulating storage form.

Unconjugated DHEA is the biologically active, rapidly fluctuating fraction of adrenal DHEA output and the immediate precursor to active androgens and oestrogens in peripheral tissues. It is clinically distinct from DHEA-S — the sulfated storage form with a 7–10 hour half-life and minimal diurnal variation — in both its measurement stability and its interpretive clinical context. Measurement of unconjugated DHEA is specifically indicated when the clinical question concerns the biologically available, rapidly responding DHEA fraction rather than the integrated long-term adrenal androgen reserve captured by DHEA-S. In functional and integrative endocrinology, DHEA is assessed in the evaluation of adrenal function, HPA axis dysregulation, androgen precursor availability, and biological ageing, with declining DHEA associated with reduced immune resilience, musculoskeletal vitality, mood, and libido across both sexes. In mainstream endocrinology, DHEA-S is generally preferred over unconjugated DHEA due to its greater analytical stability and reduced susceptibility to pre-analytical variability.

Why is the DHEA Unconjugated test ordered?

Morning adrenal function assessment alongside cortisol — unconjugated DHEA collected at the same 08:00–09:00 standardised time point as morning cortisol characterises the adrenal androgen-glucocorticoid axis simultaneously in a single draw
DHEA supplementation monitoring — patients receiving oral DHEA (bioidentical DHEA) where measurement of the unconjugated active form rather than the sulfated storage metabolite DHEA-S is the preferred monitoring strategy for the prescribing practitioner
Adrenal androgen excess investigation — elevated unconjugated DHEA alongside elevated DHEA-S and androstenedione localises androgen excess to the adrenal zone reticularis, particularly relevant in the differential diagnosis of PCOS with adrenal androgen contribution versus purely ovarian androgen excess
Suspected adrenal insufficiency or Addison's disease — subnormal unconjugated DHEA alongside reduced morning cortisol and elevated ACTH supports adrenal cortical insufficiency and completes the adrenal steroid profile
HPA axis dysregulation assessment in functional and integrative medicine — low DHEA relative to cortisol (elevated cortisol:DHEA ratio) is a functional medicine marker of adrenal dysregulation and chronic stress-associated adrenal pattern, interpreted alongside salivary cortisol rhythm
Congenital adrenal hyperplasia (CAH) investigation — markedly elevated DHEA alongside elevated androstenedione and reduced cortisol in the context of virilisation, ambiguous genitalia, or salt-wasting crisis supports CAH diagnosis pending 17-hydroxyprogesterone confirmation
Biological ageing and vitality assessment in integrative and anti-ageing medicine — DHEA as a marker of adrenarche decline in older adults, guiding decisions about DHEA supplementation as part of a broader hormone optimisation protocol
Paediatric adrenarche evaluation — assessment of premature or delayed adrenarche where DHEA and DHEA-S rise is the earliest biochemical marker of adrenal androgen zone maturation

Sample collection and turnaround

Sample type

Blood (serum)

Fasting required

Collection method

Venipuncture at patient service centre

Turnaround

2–4 business days

Collection notes

Standard venipuncture into a serum separator tube (SST / gold top). Collection must be timed to 08:00–09:00 hours — practitioners should instruct patients to book an early-morning appointment specifically and to communicate the timing requirement to the phlebotomist. The patient should arrive rested, without having engaged in vigorous exercise that morning. Document on the requisition form: (1) exact collection time; (2) current DHEA supplementation — dose, formulation, and time of most recent dose; (3) current corticosteroid use (systemic or high-dose inhaled); (4) oral contraceptive or exogenous oestrogen use; (5) whether concurrent morning cortisol is being measured. # REVIEWER FLAG: Confirm Quest Diagnostics tube type, minimum serum volume, and any special handling requirements for unconjugated DHEA before publication.

Specimen requirements

Minimum 0.5 mL serum. Centrifuge and separate serum within 2 hours of collection. Stable at 2–8°C for up to 5 days; stable frozen at −20°C for extended storage. # REVIEWER FLAG: Confirm minimum volume and stability data with Quest Diagnostics assay documentation.

What can affect DHEA Unconjugated results?

variableTime of collection — diurnal variation

Unconjugated DHEA follows a diurnal rhythm closely paralleling cortisol, peaking at approximately 08:00 hours and falling by 50–80% by late afternoon and evening. Collection outside a standardised morning window (08:00–09:00 hours) will produce results that are systematically lower than the morning reference range and cannot be compared to morning-calibrated reference intervals. This is the most important pre-analytical variable for this analyte and is the primary reason DHEA-S is preferred in routine practice — standardised morning collection is mandatory for unconjugated DHEA to be clinically interpretable.

variableAcute physical or psychological stress at collection

Activation of the HPA axis by acute stress — vigorous exercise, psychological distress, pain, or illness immediately before collection — alters adrenocortical secretion acutely, affecting both cortisol and DHEA output in ways that may not reflect the patient's habitual adrenal secretory pattern. Patients should be instructed to attend their collection appointment in a rested, non-fasted (or lightly fasted), calm state. Results obtained during acute physical or emotional stress episodes should be interpreted with caution and repeated if clinical decisions depend on them.

elevatesExogenous DHEA supplementation

Oral DHEA supplementation raises both unconjugated DHEA and DHEA-S, with the timing and magnitude of elevation dependent on dose, formulation, and individual conversion capacity. Unconjugated DHEA rises earlier and more sharply following oral dosing and declines more rapidly than DHEA-S. The timing of specimen collection relative to the most recent DHEA dose must be documented for monitoring results to be meaningful — trough (pre-dose) and peak (1–2 hours post-dose) collections serve different interpretive purposes.

reducesCorticosteroid therapy (systemic)

Exogenous glucocorticoids suppress ACTH secretion via negative feedback, reducing adrenocortical stimulation and decreasing endogenous DHEA and DHEA-S production. Patients on systemic corticosteroids — including prednisone, dexamethasone, hydrocortisone, and high-dose inhaled corticosteroids — will have suppressed unconjugated DHEA that does not reflect intrinsic adrenal reserve. Corticosteroid type, dose, duration, and last dose timing relative to collection must be documented.

reducesOral contraceptives and exogenous oestrogens

Combined oral contraceptives suppress the hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes, reducing ACTH-driven adrenal androgen production. Oestrogens also increase hepatic SHBG production and upregulate adrenal steroid sulfation, altering the DHEA-to-DHEA-S conversion ratio. Unconjugated DHEA in women on OCP reflects pharmacologically suppressed adrenal output rather than endogenous adrenal function and must be interpreted accordingly.

elevatesInsulin resistance and hyperinsulinaemia

Insulin stimulates adrenal androgen production by upregulating adrenal steroidogenic enzymes in the zona reticularis, particularly CYP17A1 lyase activity. In patients with significant insulin resistance — PCOS, metabolic syndrome, type 2 diabetes — unconjugated DHEA may be elevated through insulin-driven adrenal androgen excess independent of primary adrenal pathology. Fasting insulin and glucose should be assessed concurrently when adrenal androgen excess is investigated.

What do DHEA Unconjugated results mean?

Elevated

Elevated unconjugated DHEA (above the age-stratified upper reference limit) warrants differential assessment of adrenal androgen excess. Key differentials include adrenal zona reticularis hyperstimulation from insulin resistance or ACTH excess; congenital adrenal hyperplasia (particularly 21-hydroxylase deficiency — confirm with 17-hydroxyprogesterone measurement); adrenal androgen-secreting adenoma or carcinoma (typically causing markedly elevated DHEA and DHEA-S with rapid virilisation onset); and exogenous DHEA supplementation (always exclude before attributing to pathological adrenal excess). Mildly elevated DHEA in a young woman with PCOS features is consistent with adrenal androgen contribution to the PCOS phenotype and should be interpreted alongside LH:FSH ratio, total testosterone, SHBG, and fasting insulin. Markedly elevated DHEA — particularly values more than three times the upper reference limit — warrants adrenal imaging to exclude androgen-secreting tumour.

Normal

Normal unconjugated DHEA within the age-stratified reference range indicates appropriate adrenal androgen output at the time of standardised morning collection. In symptomatic patients — fatigue, low libido, reduced musculoskeletal vitality — a normal DHEA does not exclude functional adrenal insufficiency if the result falls in the lower tertile of the age-appropriate range; functional medicine practitioners interpret relative position within the reference interval rather than binary normal/abnormal for this marker. Concurrent assessment of DHEA-S, cortisol, and the cortisol:DHEA ratio provides a more complete picture than unconjugated DHEA in isolation.

Reduced

Reduced unconjugated DHEA (below the age-stratified lower reference limit in the absence of corticosteroid use) indicates reduced adrenal zona reticularis secretory output. In younger patients, primary adrenal insufficiency (Addison's disease), hypopituitarism with reduced ACTH drive, or prolonged HPA axis suppression from high-dose corticosteroid use are the principal differentials — assess alongside morning cortisol and ACTH. In older patients, low DHEA is an expected feature of adrenal ageing (adrenopause) and is interpreted in functional medicine as a marker of adrenal androgen reserve depletion, guiding DHEA supplementation decisions. In functional medicine, a low DHEA alongside elevated or high-normal morning cortisol (elevated cortisol:DHEA ratio) is the hallmark HPA dysregulation pattern associated with chronic stress and is a primary clinical target for adrenal support protocols.

Note: The most significant interpretive caveat for unconjugated DHEA is its mandatory requirement for standardised morning collection — results obtained outside the 08:00–09:00 window are not comparable to morning-calibrated reference ranges and should not be used for clinical decision-making. The diurnal decline of 50–80% across the day means an afternoon specimen could produce a falsely 'low' result that would prompt unnecessary clinical investigation. A second important caveat is that unconjugated DHEA is an acute-phase sensitive marker — illness, recent vigorous exercise, or emotional distress on the day of collection will alter results. For most routine adrenal androgen assessments, DHEA-S is analytically superior due to its pre-analytical stability and is the preferred marker in mainstream endocrinology; unconjugated DHEA adds specific value when real-time adrenal secretory activity, DHEA supplementation monitoring, or the DHEA:cortisol ratio in the context of HPA axis characterisation is the primary clinical question.

Frequently asked questions

DHEA unconjugated (free DHEA) is the biologically active, unsulfated form of dehydroepiandrosterone with a short half-life of 1–3 hours and pronounced diurnal variation. DHEA-S (DHEA sulfate) is the sulfated, inactive storage form with a half-life of 7–10 hours and minimal diurnal variation. DHEA-S is the standard clinical marker for adrenal androgen reserve assessment due to its analytical stability and suitability for collection at any time of day. Unconjugated DHEA is specifically ordered when real-time adrenal secretory activity, active-fraction supplementation monitoring, or the cortisol:DHEA ratio is the clinical focus.

How to access the DHEA Unconjugated test

The DHEA Unconjugated reference page is free and open to all practitioners. Create a free practitioner account to see pricing, save tests to your list, and generate requisition forms. Verification takes 1–2 business days.

Create Free Account

About this page

Published: May 23, 2026

Last reviewed: May 23, 2026

References:

This content is for licensed healthcare practitioners only and does not constitute medical advice. Clinical decisions should be based on the full clinical picture and not on any single test result.

Related tests

adrenal stress

DHEA-S

The DHEA-S (Dehydroepiandrosterone Sulfate) Serum test measures the sulfated storage form of the primary adrenal androgen prohormone — the most analytically stable adrenal androgen marker with minimal diurnal variation, suitable for collection at any time of day.

BML-ADR-011View reference →

male hormones

A4

The androstenedione test measures a 19-carbon steroid precursor to both testosterone and oestrone, secreted by the adrenal glands and gonads. It is used to investigate hyperandrogenism in women (PCOS, virilisation, adrenal or ovarian tumours), to diagnose and monitor congenital adrenal hyperplasia, and to evaluate adrenarche in children, interpreted alongside DHEA-S, testosterone, and…

BML-HRM-013View reference →