What triggers ADH?

Antidiuretic hormone (ADH, also known as vasopressin) is a hormone that regulates water reabsorption by the kidneys. It is produced in the hypothalamus and stored in the posterior pituitary gland. ADH is released in response to a number of triggers, including:

* Decreased blood volume: This can occur due to dehydration, hemorrhage, or diarrhea. When blood volume drops, the kidneys sense the change and release ADH to help retain water.

* Increased blood osmolality: This can occur due to dehydration, diabetes insipidus, or other conditions that cause the blood to become more concentrated. When blood osmolality increases, the kidneys sense the change and release ADH to help dilute the blood.

* Certain medications: Some medications, such as thiazide diuretics, can also cause the release of ADH.

* Stress: Stress can also trigger the release of ADH.

ADH works by acting on the kidneys to increase water reabsorption from the tubular fluid back into the bloodstream. This helps to maintain blood volume and blood osmolality within normal limits.