Sodium (Na)

Definition

Sodium is an electrolyte that controls the amount of fluid and the acid-base balance (pH) in the body. It also supports nerve and muscle function.

Purpose

At routine check-ups; when using medications that affect fluid balance; for symptoms suggesting abnormal sodium.

Results

High (Hypernatremia)Low (Hyponatremia)
SymptomsThirst, low urine output, vomiting, diarrhea, confusion, muscle twitchingWeakness, fatigue, confusion, muscle twitching
CausesDehydration, diuretic medications (water pills), adrenal disorders, kidney disease, diabetes insipidusSodium loss through diarrhea/vomiting; conditions causing fluid retention, kidney diseases, liver cirrhosis, heart failure, certain cancers, Addison's disease, certain medications (painkillers, antidepressants)

Normal Values

Laboratory specific.

Risks and Limitations

Must be evaluated together with other tests for diagnosis. Certain medications, your age, your sex and certain medical conditions can raise or lower your sodium levels.

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