Chemistry, toxicology & urinalysis

Organ specific


Saline suppression test

Topic Completed: 1 February 2010

Minor changes: 9 April 2020

Copyright: 2002-2021,, Inc.

PubMed Search: Saline suppression [title]

Renu Virk, M.D.
Page views in 2020: 1,331
Page views in 2021 to date: 1,222
Cite this page: Virk R. Saline suppression test. website. Accessed December 3rd, 2021.
Definition / general

  • Infuse 2L of 0.9% saline over 4 hours ("saline infusion test") OR give oral NaCl tablets 10 - 12 gm daily for 3 days ("oral sodium loading test")
  • Blood levels: plasma aldosterone greater than 5 ng/dl (140 pmol/L) confirms the diagnosis of primary hyperaldosteronism
  • Urine levels: collect 24 hour urine for aldosterone, creatinine (to assess the adequacy of urine collection), and sodium (to ensure adequate intake) on the last day of sodium chloride administration
    • Aldosterone levels > 10 μg/24 hours (28 nmol/24 hours) confirms the diagnosis
Clinical features
  • More difficult to perform than captopril suppression test, with comparable accuracy in patients with high sodium intake (Hypertension 2007;50:424)
Back to top
Image 01 Image 02