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Antidiuretic Hormone (ADH / AVP) Unit Converter
Antidiuretic Hormone (ADH), also known as Arginine Vasopressin (AVP), is a nonapeptide hormone synthesized in the hypothalamus and stored in the posterior pituitary gland. Its primary physiological role is the regulation of water balance and blood pressure.[Image of HPA axis regulation]
ADH acts on V2 receptors in the renal collecting ducts to increase water permeability, facilitating water reabsorption and concentrating the urine. Clinically, ADH measurement is crucial in the differential diagnosis of Diabetes Insipidus (central vs. nephrogenic) and the Syndrome of Inappropriate Antidiuretic Hormone (SIADH). However, ADH is notoriously unstable in plasma and has a short half-life, often requiring strict sample handling (chilled, protease inhibitors). This converter allows accurate switching between the SI unit (pmol/L) and the conventional mass unit (pg/mL).
SI Units
RecommendedPicomoles per liter (Standard International).
Conventional Units
Clinical Context
ADH levels are physiologically inappropriate if they are elevated despite low plasma osmolality (hallmark of SIADH). Conversely, in Diabetes Insipidus, ADH is either absent (Central DI) or ineffective (Nephrogenic DI) despite high plasma osmolality.
Reference ranges are highly dependent on plasma osmolality. In a state of normal hydration (osmolality ~285 mOsm/kg), ADH is typically < 4.0 pg/mL. Under water deprivation, levels should rise significantly. The conversion factor is based on MW ~1084 Da: 1 pg/mL ≈ 0.92 pmol/L (or 1 pmol/L ≈ 1.08 pg/mL).
Clinical References
How to Use This Calculator
Follow these steps to get accurate clinical conversions instantly.
Enter Values
Input your laboratory results into the corresponding unit field (e.g., pg/mL). You can use either dot or comma decimals.
Automatic Conversion
The calculator works in real-time. As you type in one field, all other units (like pmol/L) are instantly updated.
Verify Units
Check the SI Units section. pmol/L is the standard for peptide hormones in SI regions.
Reset
Use the Clear button to reset all fields before starting a new calculation.
Frequently Asked Questions & Tips
Yes. Copeptin is a more stable fragment of the ADH precursor. It correlates 1:1 with ADH release but uses different reference ranges.
Currently, all fields are editable. If a field seems locked, try clearing the form first.