Diagnosis

Your doctor will start by asking about your medical history and doing a physical examination.

However, because the signs and symptoms of hyponatremia occur in many conditions, it's impossible to diagnose the condition based on a physical exam alone. To confirm low blood sodium, your doctor will order blood tests and urine tests.

More Information

Treatment

Hyponatremia treatment is aimed at addressing the underlying cause, if possible.

If you have moderate, chronic hyponatremia due to your diet, diuretics or drinking too much water, your doctor may recommend temporarily cutting back on fluids. He or she may also suggest adjusting your diuretic use to increase the level of sodium in your blood.

If you have severe, acute hyponatremia, you'll need more-aggressive treatment. Options include:

  • Intravenous fluids. Your doctor may recommend IV sodium solution to slowly raise the sodium levels in your blood. This requires a stay in the hospital for frequent monitoring of sodium levels as too rapid of a correction is dangerous.
  • Medications. You may take medications to manage the signs and symptoms of hyponatremia, such as headaches, nausea and seizures.

Clinical trials

Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.

Preparing for your appointment

Seek emergency care for anyone who develops severe signs and symptoms of hyponatremia, such as nausea and vomiting, confusion, seizures, or lost consciousness.

Call your doctor if you know you are at risk of hyponatremia and are experiencing nausea, headaches, cramping or weakness. Depending on the extent and duration of these signs and symptoms, your doctor may recommend seeking immediate medical care.

If you have time to prepare, here's some information to help you get ready for your appointment, and what to expect from your doctor.

What you can do

  • List any symptoms you or your loved one has been experiencing and for how long.
  • Write down key medical information, including other medical problems for which you are being treated and the names of all medications, vitamins, supplements or other natural remedies you are taking.
  • Take a family member or friend along, if you are the one with symptoms of low blood sodium. Someone who accompanies you can help remember all of the information and provide support if you need immediate medical care.
  • Write down questions to ask your doctor.

For hyponatremia, some basic questions to ask your doctor include:

  • What's the most likely cause of my symptoms?
  • What causes hyponatremia?
  • How severe is the condition?
  • What treatment do you recommend?
  • How soon do you expect my symptoms will begin to improve?
  • Am I at risk of any long-term problems?
  • How can I prevent a recurrence of this condition?
  • Do I need to make any changes to how much fluid I usually drink?

What to expect from your doctor

Being ready to answer your doctor's questions may reserve time to go over any points you want to talk about in-depth. Your doctor may ask:

  • What are your symptoms and when did they start?
  • Have you started taking any new medications?
  • Have your symptoms been getting any better or worse since they first developed?
  • Have your symptoms included any mental changes, such as feeling confused, agitated or depressed?
  • Have you had nausea, vomiting or diarrhea?
  • Have you felt faint, had seizures or lost consciousness?
  • Have you had a headache? If yes, has it gotten progressively worse?
  • Have your symptoms included weakness, fatigue or lethargy?
  • Do you use recreational drugs? If yes, which drugs?
May 17, 2022
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