ADH, Vasopressin, CT proAVP, C-Terminus Pro-Arginine Vasopressin

Collection Requirements

Morning samples after 8 hour fast (without water restriction) are recommended unless otherwise stated by clinician.

Tube Colour


Test image(s)

Requires own tube?




Reference Interval

A random copeptin of ≥ 21.4 pmol/L is consistent wtih nephrogenic diabetes insipidus. In a hypertonic saline infusion test, once plasma sodium is ≥ 147 mmol/L, a copeptin of > 4.9 pmol/L suggests primary polydipsia and a copeptin of ≤ 4.9 pmol/L is consistent with central diabetes insipidus. Reference: Christ-Crain et al, J Clin Endocrinol Metab 2022; 1727-1738.



Reference Laboratory

Northern Pathology Victoria. Specimen Reception, Northern Hospital. 185 Cooper St Epping Vic 3076 (P) 03 84058351


AUD $50 not Medicare rebatable


Copeptin (aka C- Terminus Pro-Arginine Vasopressin, CT-proAVP) is the C-terminal glycoprotein moiety of pre-provasopressin and is released in the same amount as AVP and can be used as a surrogate for ADH concentration. Copeptin has a much longer plasma half-life than ADH (days compared to minutes) and has greater stability at room temperature and therefore is less prone to preanalytical errors.

Test code: COPEP

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