Potassium Test

A potassium test, also known as a serum potassium test, is a medical laboratory test used to measure the level of potassium ions (K+) in the blood.

Why is it performed?

The test is typically performed to:

• Evaluate kidney function and diagnose kidney disorders
• Monitor patients with heart conditions, such as arrhythmias or cardiac arrest
• Assess muscle weakness or paralysis
• Diagnose and monitor hormonal imbalances, such as adrenal gland disorders
• Monitor patients taking certain medications that can affect potassium levels, such as diuretics

How is it performed?

The test involves drawing a blood sample from a vein in the arm using a needle and syringe or a blood collection device. The blood sample is then sent to a laboratory for analysis.

What do the results mean?

A normal potassium level typically ranges from 3.5 to 5.0 milliequivalents per liter (mEq/L) of blood. Abnormal results may indicate:

• Hyperkalemia (high potassium levels): can be caused by kidney disease, certain medications, or excessive dietary intake
• Hypokalemia (low potassium levels): can be caused by kidney disease, certain medications, or inadequate dietary intake

Risks and complications

The risks associated with a potassium test are minimal and may include:

• Bleeding or bruising at the needle site
• Infection at the needle site
• Lightheadedness or dizziness due to blood draw

Preparation

No special preparation is typically required for a potassium test. However, patients may be asked to:

• Fast for a certain period before the test
• Avoid taking certain medications that can affect potassium levels

Interpretation and follow-up

The results of a potassium test should be interpreted by a healthcare professional, who will consider the patient's medical history, symptoms, and other laboratory test results to diagnose and manage any underlying conditions.