Dexamethasone suppression tests

SPEG (Scottish Paediatric Endocrine Group)
NHS National Services Scotland

Introduction

There are several forms of the dexamethasone suppression test:

  1. Overnight dexamethasone suppression test.
  2. Low dose dexamethasone suppression test.
  3. High dose dexamethasone suppression test.

The overnight dexamethasone suppression test is used as an initial screening test.

If there is a failure of suppression, a prolonged dexamethasone test may be required. This should be discussed with your local tertiary endocrinologist.

In this case a prolonged (low or high dose) Dexamethasone suppression test may help confirm Cushing’s syndrome and identify the cause.