The common side effects of having low potassium levels, or hypokalemia, include cramping, tiredness and muscle weakness, according to MedicineNet. Heart arrhythmia can occur if potassium levels are extremely low, states Mayo Clinic.
The side effects may not be present until potassium levels are very low, asserts the Scott Hamilton CARES Initiative. Low potassium levels can be caused by taking medications like Prednisone and certain diuretics, laxatives, diarrhea, GI tract problems and decreased magnesium levels, notes MedicineNet. Normal potassium levels are important for the proper functioning of the nervous system, the heart and the muscles. Potassium levels are considered low when they are lower than 3.5 milliequivalents per liter. Potassium levels can be monitored through routine blood tests, and changes in the level can appear in electrocardiograms.
To treat potassium levels that are dangerously low, patients are given medications, including potassium-sparing diuretics that help keep the electrolyte in the blood and magnesium or potassium supplements, according to the Scott Hamilton CARES Initiative. Potassium can also be given intravenously, but overuse of this treatment can cause heart problems, notes MedicineNet. Doctors may also advise their patients to reduce or change their current medications that could be contributing to low potassium levels, asserts Mayo Clinic. Starting a diet of foods rich in potassium, such as bananas, tomatoes and meat, can increase potassium levels naturally, according to MedicineNet.