What Happens When Your Potassium is Low (Hypokalemia)?

The effects of low potassium include may cause heart palpitations, muscle cramps, muscle aches, and muscle weakness.

Potassium enters the body through diet and is one of the primary electrolytes (crucial chemicals for cell function) and is concentrated within the cells of the body. Only 2% of the body's total potassium is available in the serum or bloodstream. Small changes in the serum levels of potassium can affect body function. One of the more important functions of potassium is to maintain the electrical activity of the cells in the body. Cells with high electrical activity (for example, nerves and muscles, including the heart) are particularly affected when potassium levels fall.

• Normal serum potassium levels range from 3.5 to 5.0 mEq/liter in the blood.
• Normal daily intake of potassium is 70-100 mEq (270 to 390 mg/dl) and requires the kidneys to remove that same amount each day.
• If more is removed, the body's total potassium store will be decreased, and the result is hypokalemia (hypo=low + kal=potassium +emia= in the blood) occurs.

Hypokalemia is not commonly caused by poor dietary intake.

The most common reason that potassium levels fall is due to the loss of the gastrointestinal (GI) tract and the kidney.

Potassium loss from the GI tract may be caused by:

• Vomiting
• Diarrhea
• Ileostomy: In some patients who have had bowel surgery and have an ileostomy, the stool output can contain significant amounts of potassium.
• Villous adenoma (a type of colon polyp that can cause the colon to leak potassium)
• Laxative use

Causes of potassium loss from the kidney:

• Diuretic medications (water pills) like hydrochlorothiazide (HCTZ) or furosemide (Lasix)
• Elevated corticosteroid levels, either from medication like prednisone or from an illness like Cushing's syndrome
• Elevated levels of aldosterone, a hormone that can increase with renal artery stenosis or adrenal tumors
• Renal tubular acidosis
• Low body magnesium levels

Low potassium levels may result from side effects of some medications:

• Aminoglycoside antibiotics like gentamicin (Garamycin) or tobramycin (Nebcin)
• Amphotericin B
• Prednisone

Potassium affects the way neuromuscular cells discharge energy (depolarize) and then regenerate (repolarize) that energy to be able to fire again. When potassium levels are low, the cells cannot repolarize and are unable to fire repeatedly, and muscles and nerves may not function normally. This condition, known as hypokalemia, can result in various symptoms.

The effects of low potassium include the following low potassium symptoms:

• muscle weakness,
• muscle aches,
• muscle cramps, and
• heart palpitations (irregular heartbeats).

In more severe cases of hypokalemia, additional symptoms such as fatigue, constipation, and respiratory issues may also occur.

Potassium levels in the blood may be easily measured by routine blood tests.

Low potassium is often a potential complication of medication. For example, patients with high blood pressure who are being treated with diuretics such as hydrochlorothiazide (Hydrodiuril) or furosemide (Lasix) often have their potassium levels monitored.

Patients who become ill with vomiting and diarrhea might develop dehydration and weakness. Part of the patient evaluation may include having their electrolyte levels tested to determine whether body potassium losses may need to be replaced.

There can be electrocardiogram (EKG, ECG) changes associated with low potassium, and sometimes the diagnosis of hypokalemia is made incidentally by finding the characteristic "U" waves on the EKG tracing. In severe cases, hypokalemia can lead to dangerous disturbances in heart rhythm (dysrhythmia). These EKG changes are important indicators of hypokalemia and can help guide treatment decisions. Monitoring these changes is essential, especially in patients at risk for hypokalemia.

Serum potassium levels above 3.0 mEq/liter are not considered dangerous or of great concern; they can be treated with potassium replacement by mouth. Depending on the patient's medical condition, other medical problems, and the patient's symptoms, serum levels lower than 3.0 mEq/liter may require intravenous replacement. Decisions are patient-specific and depend upon the diagnosis, the circumstances of the illness, and the patient's ability to tolerate fluid and medication by mouth.

Over the short term, with self-limited illnesses like gastroenteritis with vomiting and diarrhea, the body can regulate and restore potassium levels on its own. However, if the hypokalemia is severe, or the losses of potassium are predicted to be ongoing, potassium replacement or supplementation may be required.

In those patients taking diuretics, often a small amount of oral potassium may be prescribed since the loss will continue as long as the medication is prescribed. Oral supplements may be in pill or liquid form, and the dosages are measured in mEq (milliequivalents). Common doses are 10-20 mEq per day. Alternatively, consumption of foods high in potassium may be the first option in replacing potassium. Bananas, apricots, oranges, and tomatoes are high in potassium content. Since potassium is excreted in the kidney, blood tests that monitor kidney function may be ordered to predict and prevent potassium levels from rising too high.

When potassium needs to be given intravenously, it must be given slowly. Potassium is irritating to the vein and is usually administered at a maximal rate of 10 mEq per hour. Moreover, infusing potassium too quickly can cause heart irritation and promote potentially dangerous rhythms such as ventricular tachycardia, particularly in cases of severe hypokalemia. Close monitoring during the infusion is essential to prevent complications associated with hypokalemia.

How long does it take to recover from low potassium?

The recovery time for hypokalemia can vary significantly depending on the severity of the deficiency, the underlying cause, and the treatment approach. For mild cases treated with dietary changes or oral potassium supplements, improvement can often be seen within a few days. However, in more severe cases of hypokalemia, requiring intravenous potassium, levels may normalize within hours, although monitoring will continue to ensure stability.

Factors such as individual health status, kidney function, and treatment adherence also influences recovery time. It is crucial to adhere to a health care provider’s recommendations and closely monitor potassium levels during recovery to avoid recurrence or complications.

Is low potassium dangerous?

What happens when your potassium is low? Rarely, a special situation will occur when all the potassium in the body shifts from the serum into the cells of the body. This drops the serum potassium levels to 1.0 mEq/liter or lower. This causes immediate muscle weakness to the point that the patient cannot move and becomes paralyzed. Arms and legs are most affected. Rarely, breathing and swallowing muscles can be involved.

Periodic paralysis may be hereditary (genetic) and may be precipitated by excessive exercise, high carbohydrate or high salt meal, or may occur without apparent cause.

Treatment by potassium replacement intravenously for hypokalemia is effective, and recovery occurs within 24 hours. This method is particularly important in cases of severe hypokalemia, where rapid correction is necessary to prevent complications. Continuous monitoring is essential to ensure that potassium levels return to normal and to avoid the risk of hyperkalemia following treatment.

Usually, the body can maintain potassium levels within the normal range as long as there is adequate potassium in the diet. When the body loses potassium due to a short-term illness, it can compensate for the loss. If your potassium loss continues, you and your doctor need to anticipate the loss and consider routine potassium replacement.

Early intervention is essential to prevent the development of hypokalemia, especially in individuals at higher risk, such as those on certain medications or with specific medical conditions. Regular monitoring of potassium levels can also help identify potential hypokalemia before it becomes severe.

Potassium is an essential micro-mineral in the body.

Potassium enters the body through dietary intake. Examples of potassium-rich foods include:

• Fresh fruits: bananas, cantaloupe, oranges, strawberries, kiwi, avocados, apricots
• Fresh vegetables: greens, mushrooms, peas, beets, tomatoes
• Meats: beef, fish, turkey
• Juices: Orange, prune, apricot, grapefruit

• Is hypokalemia life-threatening? Yes, hypokalemia can be life-threatening, particularly when potassium levels drop significantly, leading to severe complications such as cardiac arrhythmias, muscle weakness, and respiratory failure. The risk is higher in individuals with underlying health conditions or those on certain medications. Timely diagnosis and treatment are essential to prevent serious complications.
• What is the first-line treatment for hypokalemia? The first-line treatment for hypokalemia is oral potassium supplementation, typically with potassium chloride. However, if the patient has severe hypokalemia or significant symptoms, intravenous potassium may be necessary. It is important to monitor serum potassium levels and renal function during treatment to avoid hyperkalemia. Dietary modifications to increase potassium intake can also be beneficial.
• How do you correct hypokalemia? To correct hypokalemia, potassium levels can be restored through oral or intravenous potassium supplementation, depending on the severity of the condition. Monitoring serum potassium and renal function is essential to ensure safe and effective correction while avoiding complications such as hyperkalemia. Additionally, addressing underlying causes, such as dietary deficiencies or medications that promote potassium loss, is crucial for long-term management.
• What hurts when your potassium is low? When potassium levels are low, individuals may experience muscle cramps, weakness, and general fatigue due to impaired muscle and nerve function. Severe hypokalemia can lead to muscle pain or myopathy, and in some cases, it may cause abdominal discomfort or cramps due to impaired gastrointestinal motility. Prompt recognition and treatment are essential to alleviate these symptoms.
• How can I raise my potassium level quickly? To quickly raise potassium levels, you can consume potassium-rich foods like bananas, avocados, sweet potatoes, and leafy greens. Oral or intravenous potassium supplements may be needed for more severe cases, but this should always be done under medical supervision to ensure safety and prevent complications. Regular monitoring of potassium levels is crucial during the correction process.