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"Should I be concerned with a magnesium RBC at 4.3?"

ZocdocAnswersShould I be concerned with a magnesium RBC at 4.3?


Doctor ran test due to memory loss after surgery; numbness around lips and numbness / tingling in upper leg. Chronic Charlie horse pain in calves at night


Thank you for your question. I would strongly recommend that you discuss your results with your primary care physician or the physician who ordered these blood tests. It is difficult to precisely answer your question because serum magnesium and red blood cell count (RBC) are two separate laboratory tests, and I am not sure which value the 4.3 refers to. The normal range for serum magnesium is generally ~1.7 to 2.6. If your levels were elevated as high as 4.3, the most likely symptoms that you would experience would be nausea, flushing, drowsiness, and lethargy. Interestingly, high levels of magnesium can lead to low levels of calcium, which could cause numbness around the mouth in addition to numbness and tingling in the hands and feet, as you describe. Separately, if you are referring to your RBC count, a value of 4.3 would be slightly low (normal is ~4.5 to 6.4). This could mean that you are anemic, although the hemoglobin and hematocrit should be used to determine if this is the case. Symptoms of anemia can include shortness of breath, a pale appearance, and increased heart rate. There are many causes of anemia, so I would again strongly recommend that you discuss the laboratory results more closely with the physician who ordered these tests.

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