What is the syndrome of inappropriate antidiuretic hormone secretion (SIADH)? — The syndrome of inappropriate antidiuretic hormone secretion (also called "SIADH") is a condition that happens when your body makes too much antidiuretic hormone (also called "ADH"). ADH helps manage the amount of water in your body. If you have too much ADH, your kidneys can't get rid of water. Fluid builds up in your body and dilutes the amount of salt in your blood. This causes a condition called "hyponatremia."
What causes SIADH? — Many things can cause SIADH, including:
Medicines – These include certain medicines used to treat type 2 diabetes, high blood pressure, seizures, and cancer.
Infections such as pneumonia
Brain and spinal cord problems – This includes strokes, bleeding, or an infection in your brain.
Cancer – This includes different types of lung cancer (especially small cell) and cancer of the stomach, pancreas, or brain.
What are the symptoms of SIADH? — The symptoms are the same as the symptoms of hyponatremia and include:
Nausea and vomiting
Confusion or trouble thinking clearly
Feeling weak or tired
Feeling restless or irritable
Muscle weakness, spasms or cramps
Seizures or passing out
Is there a test for SIADH? — Yes. Tests include blood and urine tests.
How is SIADH treated? — That depends on what is causing your SIADH. For example, if you have an infection, your doctor might prescribe medicines to treat it. He or she might also tell you to:
Limit the amount of fluids you drink
Eat salt tablets or get a salt-water solution into a vein
Stop taking a medicine that is causing the problem
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This topic retrieved from UpToDate on: Mar 30, 2020.
Topic 86640 Version 4.0
Release: 28.2.2 - C28.105
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