Overnight dexamethasone suppression tests (DFT)

Test/Investigation

Overnight dexamethasone suppression tests (DFT)

Site(s) or Laboratory offering Test/Investigation

NNUH, JPUH, QEH (Biochemistry)

Indications

This test is to see whether the body can appropriately 'switch off' production of the hormone cortisol

Comments/Precautions

Please refer to local trust guidelines for DFT protocols.

Sample type

1 x Serum sample. Refer to local DFT guidelines for timings

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

Please refer to the individual tests included in this dynamic function test for turn-around times.

Reference intervals (adult unless stated)

A normal response is suppression of 09:00h Cortisol to <50nmol/L

If UKAS Accredited Test indicate at which site

Please refer to the individual tests included in this dynamic function test