While there are many causes of low potassium in the blood, the most common is the loss of potassium in the urine due to prescription diuretics, indicates Mayo Clinic. Other causes include excess sweating, overuse of alcohol or laxatives, diarrhea and vomiting. Diabetic ketoacidosis and chronic kidney disease are additional causes.
Potassium is an electrolyte in the blood stream. Doctors often order blood tests to determine potassium levels in patients who take diuretics, suffer certain illnesses or have muscle cramps. Its normal concentration is between 3.6 and 5.2 millimoles per liter. Potassium levels below 2.5 millimoles per liter can be life threatening, states Mayo Clinic.
Common symptoms of low potassium include muscle cramps, fatigue, weakness and constipation, according to Mayo Clinic; however, the most worrisome complication of the condition is abnormal heart rhythms. The condition is more serious in patients with underlying heart conditions.
When a patient receives a diagnosis of low potassium levels, he should work with his doctor to develop a treatment plan, advises Mayo Clinic. The plan sometimes requires a change of medication if the medication is causing the low potassium problem. If it is from another underlying issue, the treatment plan must address that issue. While potassium supplements are available, patients should not begin use of these medications without the prior approval of their doctor.