Dexamethasone Suppression Test

Differentiation between adrenal and pituitary Cushing’s disease

Serum 2 x 0.5 ml or 3 x 0.5 ml

• First blood collection = baseline value
• Injection of 0.1 mg (dog) or 1.0 mg (cat) of dexamethasone/kg bdw i.m. or i.v.
• An additional sample 4 hours post injection gives information concerning a delayed decrease of cortisol.
• Blood sample 8 hours post injection = suppression value

Cortisol

Dog, cat

• Pituitary: one or both suppression values < 10 ng/ml
  (in rare cases suppression values > 10 ng/ml)
• Adrenal: both suppression values > 10 ng/ml