A low potassium level is 2.5 millimoles per liter or below and is a life-threatening medical emergency, notes Mayo Clinic. With a potassium level that low, a person feels side effects such as fatigue, muscle spasms and abnormal heart rhythm. Potassium controls muscle function, and the heart is a muscle.
Constipation and weakness are also common side effects present in a person with a low potassium level, as stated by WebMD. Tingling or numbness, abdominal pain, passing large amounts of urine, and feeling extremely thirsty may also indicate low potassium levels in the body. Potassium deficiency can impact the heart, nerves and muscles. Doctors take low potassium very seriously, and they normally test a person with an EKG machine to monitor the heart. A blood test checks electrolyte imbalance, including magnesium, calcium and phosphorus as well as potassium.
Some people, such as bariatric surgery patients, people with eating disorders, and alcoholics, have issues maintaining potassium levels at a normal range due to medical or mental disorders, as noted by WebMD. For people without any special medical circumstance or those who are not taking medications such as diuretics, low potassium symptoms are normally very mild and somewhat vague. Normal potassium levels are 3.6 to 5.2 millimoles per liter.