Hypophosphatemia
Definition
Hypophosphatemia is a low level of phosphorus (phosphate) in the blood.
Alternative Names
Low blood phosphate; Phosphate - low; Hyperparathyroidism - low phosphate
Causes
The following may cause hypophosphatemia:
- Alcoholism
- Antacids
- Certain medicines, including insulin, acetazolamide, foscarnet, imatinib, intravenous iron, niacin, pentamidine, sorafenib, and tenofovir
- Fanconi syndrome
- Fat malabsorption in the gastrointestinal tract
- Hyperparathyroidism (overactive parathyroid gland)
- Starvation
- Too little vitamin D
Symptoms
Symptoms may include:
- Bone pain
- Confusion
- Muscle weakness
- Seizures
Exams and Tests
Your health care provider will examine you.
The following tests may be done:
- Kidney function tests
- Parathyroid hormone level
- Vitamin D blood test
Exam and testing may show:
- Anemia due to too many red blood cells being destroyed (hemolytic anemia)
- Heart muscle damage (cardiomyopathy)
Treatment
Treatment depends on the cause. Phosphate can be given by mouth or through a vein (IV).
Outlook (Prognosis)
How well you do depends on what has caused the condition.
When to Contact a Medical Professional
Contact your provider if you have muscle weakness or confusion.
References
Chonchol M, Smogorzewski MJ, Stubbs, JR, Yu ASL. Disorders of calcium, magnesium, and phosphate balance. In: Yu ASL, Chertow GM, Luyckx VA, Marsden PA, Skorecki K, Taal MW, eds. Brenner and Rector's The Kidney. 11th ed. Philadelphia, PA: Elsevier; 2020:chap 18.
Klemm KM, Klein MJ, Zhang Y. Biochemical markers of bone metabolism. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 16.
Yu ASL. Diseases of magnesium and phosphorus. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 105.