Synacthen Stimulation Test

Testing Laboratory

Auckland Te Toka Tumai | Auckland Hospital

Department

Chemical Pathology

Delphic Registration Code (Alpha Code)

COR

Test Code (Numeric Code)

3005

Laboratory Handling

Phlebotomy

The test can be performed at any time of the day. Please refer ADHB Outpatient requests to the Endocrinology Clinic at Greenlane Clinical Centre. Requests from GPs for this test should be directed to the Endocrinology Outpatient Service at Greenlane Clinical Centre for booking (see Endocrine Nurse numbers) .

Registration

Synacthen Stimulation Test - Cortisol {Heparin, Plain, EDTA - Two separate numbers are to be used as these samples are Pre and Post timed.}.

Sample Stability

See additional information

Synonyms

[ACTH stimulation test]

Turnaround Time

3 hours

Specimen Type

  • Plasma

Specimen Requirements

Tube/Container Type:

Preferred
  • Lithium Heparin PST- Gel (Light Green Cap)
Preferred Sample Volume (ml)

5

Paediatric Specimen Requirements

Tube/Container Type:

Preferred
  • Lithium Heparin PST- Gel (Light Green Cap)

Additional Specimen Information

PROCEDURE:
The test can be performed at any time of the day.

Please refer ADHB Outpatient requests to the Endocrinology Clinic at Greenlane Clinical Centre.

Requests from GPs for this test should be directed to the Endocrinology Outpatient Service at Greenlane Clinical Centre for booking (see Endocrine Nurse numbers) .

The Synacthen is obtained from Pharmacy, not the laboratory. Synacthen is a synthetic form of ACTH.

1. Insert a butterfly needle into the vein. Withdraw the pre-synacthen cortisol sample: 5 mL blood into a heparin PST tube. Request " cortisol " on the form, write the time, and send immediately to the laboratory. If ACTH is required also collect 5 mL blood into a chilled EDTA tube (on ice).

2. Infuse 250 ug synacthen over 1 minute. The butterfly needle can now be removed or flushed with saline and kept in.

3. After 30 minutes, withdraw the post-synacthen cortisol sample: 5 mL blood into a heparin PST tube. Use a separate form, request " post-synacthen cortisol" , write the time, and send in a separate bag. (If the butterfly has been kept in, first withdraw enough blood to wash out the saline before collecting the blood sample; dilution with saline will give a false low result).

Last updated: 09/03/2026