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Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH): Care Instructions

Your Care Instructions

Antidiuretic hormone (ADH) is a chemical made in the brain. It causes the kidneys to release less water. This reduces the amount of urine. At times, ADH levels are higher than they should be. This can happen if you have certain health problems. It is known as syndrome of inappropriate antidiuretic hormone secretion (SIADH).

SIADH may occur with lung disease or cancer. It can also happen with diseases of the brain and spinal cord. Using certain medicines may also cause it.

SIADH can cause fluid to build up in your body. It may cause hyponatremia (say "hy-po-nuh-TREE-mee-uh"). This is a low level of sodium in the blood. If this happens, the balance of fluid and sodium in your body isn't normal. You may have symptoms such as loss of appetite, nausea, vomiting, and headaches.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

How can you care for yourself at home?

  • If your doctor tells you to, take pills or drink fluids that contain sodium (such as sports drinks). Or you can eat salty foods.
  • Limit your intake of water, tea, coffee, juices, and other liquids that are mostly water, as your doctor advises.
  • Be safe with medicines. Take your medicines exactly as prescribed. Call your doctor or nurse advice line if you think you are having a problem with your medicine.
  • Get your sodium levels tested as your doctor recommends.

When should you call for help?

Call 911 anytime you think you may need emergency care. For example, call if:

  • You have a seizure.
  • You passed out (lost consciousness).

Call your doctor or nurse advice line now or seek immediate medical care if:

  • You are confused or have trouble focusing.

Watch closely for changes in your health, and be sure to contact your doctor or nurse advice line if:

  • You do not get better as expected.

Care instructions adapted under license by your healthcare professional. If you have questions about a medical condition or this instruction, always ask your healthcare professional. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.