Definition: Hypokalemia is the medical name for a lower than normal amount of potassium in the blood. MedlinePlus gives the normal range as 3.5 to 5.1 mEq/L. Potassium is a mineral cells need to work properly, including heart and muscle cells.
MedlinePlus lists common causes such as water pills (diuretics), diarrhea or vomiting, laxative overuse, low magnesium and some kidney and hormone conditions. A small drop often causes no symptoms, or mild ones such as constipation, fatigue, muscle weakness or spasms, tingling and a feeling of skipped heartbeats. A large drop can cause abnormal heart rhythms, and a very low level can stop the heart.
Every insulin label in Dose Track's set, from rapid-acting to NPH and inhaled insulin, carries the same warning: all insulins shift potassium from the blood into cells and can cause low potassium, which untreated can cause breathing paralysis, heart rhythm problems and death.
The Humulin R label says that when it is given into a vein, both blood sugar and potassium are checked closely. MedlinePlus says a mild low is usually treated with potassium pills, and a severe one may need potassium through a vein. A blood test checks the level, and an ECG may be done to check the heart.
Potassium is on a basic blood panel. Logging results with the date and your insulin doses at the time gives your prescriber a timeline to look at. If you also take a water pill or have had a stretch of vomiting or diarrhea, noting that on the same day adds the other causes MedlinePlus lists.
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