What Is Aldosterone?
Aldosterone is a steroid hormone made by the adrenal glands (outer layer). It regulates blood pressure by controlling how much sodium your kidneys retain and how much potassium they excrete.
Normal Aldosterone Levels
| Position | Normal Range |
|---|---|
| Seated (upright) | 4–31 ng/dL |
| Supine (lying down) | 1–16 ng/dL |
The aldosterone-to-renin ratio (ARR) is often more useful than aldosterone alone.
Causes of High Aldosterone (Hyperaldosteronism)
- Primary hyperaldosteronism (Conn's syndrome) — adrenal adenoma or bilateral hyperplasia
- Causes resistant high blood pressure and low potassium
- Secondary hyperaldosteronism — from kidney disease, heart failure, or excessive diuretic use
Causes of Low Aldosterone (Hypoaldosteronism)
- Addison's disease (adrenal insufficiency)
- Hyporeninaemic hypoaldosteronism — seen in some kidney diseases
- Medications: NSAIDs, ACE inhibitors can suppress aldosterone
High Blood Pressure + Low Potassium?
This combination strongly suggests primary hyperaldosteronism — a potentially curable cause of hypertension if treated surgically. Aldosterone and renin testing is the first step.
FAQs
What medications affect aldosterone testing?
ACE inhibitors, ARBs, diuretics, spironolactone, and beta-blockers can all affect results — your doctor may ask you to hold them.
How is the aldosterone test done?
A blood sample is taken after sitting or standing for 15–30 minutes. A 24-hour urine collection may also be requested.
Can aldosterone cause weight gain?
Excess aldosterone causes sodium and water retention, which can cause mild fluid-related weight gain and puffiness.
Medical Disclaimer: Aldosterone testing is complex — medications, posture and diet affect results. Always done with medical supervision and combined with renin measurement.