Short Synacthen Test (SST)


Short Synacthen Test (SST)

Site(s) or Laboratory offering Test/Investigation



Adrenal failure. (NB Prednisolone cross reacts with cortisol assays. This information is for use with adults not children). No dietary restrictions for this test. Test should be performed in the morning when cortisol levels are at highest.

Sample type

•Take one plain clot sample of blood for cortisol clearly marking the bottle as '0' minutes. •Inject Synacthen 250mcg intramuscular •30 mins after injection take further plain clot sample of blood. Clearly mark tube '30' minutes.

Turnaround times (TAT) Urgent/Routine/GP or OPD

1 hour / 4 hour / by 8am next day

Reference intervals (adult unless stated)

30 min Cortisol should be above 450 nmol/L