Cushing syndromeRefer

• Dexamethasone (1 mg overnight suppression test)

• Exclude steroid use first: Ask about tablets, injections, inhalers, skin creams and herbal or 'desi' powders (often steroid-laced); never stop long-term steroids suddenly — taper (adrenal crisis) (Pituitary Soc 2021)
• While awaiting endocrinology: Treat BP, diabetes and low K⁺; endocrinology confirms with 24-h urine free cortisol or late-night salivary cortisol, then ACTH and imaging (Pituitary Soc 2021)

First exclude steroid use, including creams, inhalers and injections.

First visit

• 1 mg overnight dexamethasone suppression test — Cortisol at 8 am over 1.8 µg/dL is abnormal.
• Late-night salivary cortisol or 24-hour urine free cortisol — Second screening test.

Only if indicated

• ACTH — After cortisol excess is confirmed — separates pituitary/ectopic from adrenal.
• MRI pituitary or CT adrenals — Guided by ACTH.
• Blood glucose, BP, potassium, DEXA — Complications.