Hypomagnesemia, an electrolyte imbalance marked by low levels of magnesium in the blood, is a medical condition that can lead to various health complications. There are several synonyms or alternative names for this condition, including magnesium deficiency, low magnesium, and hypomagnesaemia (British spelling). Other related terms include hypermagnesemia (high magnesium), magnesium wasting syndrome, and hypocalcemia-magnesium disorder. Symptoms of hypomagnesemia may range from muscle weakness and tremors to heart arrhythmias and seizures. Treatment typically involves magnesium supplementation, addressing the underlying cause, and monitoring of related electrolyte balances such as calcium and potassium.