Hypophosphatemia

Hypophosphatemia is an electrolyte and metabolic condition in which the blood phosphate level falls below normal. Mildly low levels often cause no health problem, whereas inherited forms such as X-linked hypophosphatemia begin in early childhood and are rare. Causes include alcohol misuse, starvation or poor intake, vitamin D deficiency, hyperparathyroidism, fat malabsorption, Fanconi syndrome, and some medicines such as antacids and diuretics. Typical features are muscle weakness, bone pain, confusion and seizures, and severe depletion can become life-threatening; prolonged deficiency softens bone, causing rickets in children and osteomalacia in adults. A blood phosphate test confirms it, and kidney function, parathyroid hormone and vitamin D tests help identify the underlying cause. Treatment depends on that cause, with phosphate replacement given by mouth or vein, and early treatment of inherited forms limits skeletal complications.

Seek urgent care for unusual bleeding or bruising, breathlessness at rest, or a swollen painful leg. See a doctor for persistent tiredness, pale skin, or any symptom of anaemia in a man or a woman after the menopause, which always needs a cause to be found. Call the local emergency number for any symptom that is sudden and severe. This page is a reference for healthcare professionals and does not replace an assessment.