Magnesium

About This Test
Magnesium is an essential mineral that helps regulate heart rhythm, nerve signals, and muscle contraction, and it supports energy production and bone health. Low levels can cause muscle cramps, palpitations, weakness, or tingling; high levels are less common and usually linked to kidney problems or excess supplements. Blood magnesium can look normal even when body stores are low, so doctors often interpret it with potassium, calcium, and kidney tests. This test is commonly included in routine check-ups to screen for potential problems early.

Patient Preparation
No fasting needed

Best Time to Test
Anytime

Tests Included
Magnesium

Why is it done
Evaluation of muscle cramps, twitches, weakness, or irregular heartbeat; monitoring in diabetes, alcohol use disorder, or malabsorption; checking levels when on diuretics, proton-pump inhibitors, or magnesium supplements; assessment of kidney disease or electrolyte disturbances; follow-up of previously low magnesium.