Hypokalemia

[thyroida]

Dear Dr. Nundy, I was diagnosed Hypokalemia with a potassium level of 3.1 (range 3.5-5.5).  My levels are jumping from 3.6 to 3.1 (multiple times tested low).  Would you consider potssium 3.1 dangerously low, and is it normal for potassium levels to fluctuate by this much?

[Shantanu Nundy, MD]

In theory yes though I have not personally a level of 3.1 cause an arrythmia. That being said, if one of my patients had a level of 3.1, I would likely work it up (as I discussed in my earlier response) and in the meantime replete the potassium level and re-check a week or two later.

Hope this helps. Next step is to talk with your doctor.

- Dr. Nundy

[thyroida]

Thank you for your response.  Is a potassium level of 3.1 low enough to cause arythmias?

[Shantanu Nundy, MD]

Thanks for your question. Hyper-kalemia (high potassium) is generally considered more dangerous than hypo-kalemia; however, hypokalemia can lead to arrythmias or other serious medical problems. More important than the absolute number is the rate of change. If your potassium is chronically low, that is generally less concerning. Potassium levels can vary this much. I've heard it said that a eating a banana increases potassium levels by 0.3-0.4.

Hypokalemia is generally a problem of excess potassium loss. We excrete potassium in stool or in urine so chronic diarrhea and polyuria (excess urination) are common causes. With hypokalemia I'd first be interested in finding out the cause. If that cause is say chronic diarrhea, then the best way to correct your potassium is to fix the chronic diarrhea. If there is no identifiable or easily correctable cause for your hypokalemia you can increase potassium in your diet.