R U H Bath, return to home page

Pathology Departments Requesting & Reporting Blood Test Information Phlebotomy Guide Contact us
Blood Sciences

Blood Test Information

minimum sample volume required ~ 4ml

  back to assay index

Test Code: ACT

Tube type: EDTA

Special instructions
Needs to be in the laboratory ASAP (must be frozen within 30 mins of collection).

All results must be interpreted in the context of the current cortisol levels, the time of sample collection and the clinical status of the patient.
Sent away to Bristol Royal Infirmary

Reference range
5.0 - 50.0


Linked to

Turnaround Time
4 days

Department: Biochemistry

Clinical Application
ACTH (adrenocorticotropic hormone) is secreted by the anterior pituitary in response to corticotrophin-releasing hormone from the hypothalamus as well as in response to stress.

ACTH stimulates secretion of steroids including cortisol from the adrenal cortex.

ACTH is used in the investigation of Cushing's syndrome, and in differentiating primary from secondary causes of adrenal insufficiency. A sample for measurement of ACTH should be sent with the basal cortisol of a short synacthen test when this is performed in hospital, prior to commencing steroid cover. ACTH measurement will be undertaken if the short synacthen test is abnormal. Also useful in differentiation of cause of Cushing's syndrome (pituitary, adrenal or ectopic cause), but NOT in making the diagnosis of the syndrome itself (levels can be very low to very high depending on cause).

Webpage updated: June 2024


back to top