Parenteral iron can lead to hypophosphataemia, which is temporary and without clinical symptoms in most cases. Hypophosphataemia requiring treatment has been reported in individual cases, predominantly in patients with known risk factors or following long-term high dosage. It may result in hypophosphataemic osteomalacia and fractures.
Parenteral iron products and hypophosphataemia
Incident data |
Description |
|---|---|
Case: 2019 Age group: 36 Sex: female Medicinal product: Ferinject Active substance: Iron as ferric carboxymaltose Indication: Iron deficiency ADR: Hypophosphataemia Outcome: recovering |
Two days after an infusion of 1000 mg Ferinject, the patient presented at the emergency department feeling unwell with headaches, chills and pronounced myalgia and asthenia. Laboratory tests showed hypophosphataemia of 0.69 mmol/L (normal range 0.87-1.45), which rapidly fell to 0.33 mmol/L. One month earlier, normal serum phosphate of 0.90 mmol/L had been measured in the patient. Phosphate capsules corresponding to a daily dose of 27 mmol inorganic phosphate were prescribed and the patient was discharged from inpatient treatment after a few days. Hypophosphataemia of renal origin with probable multifactorial hyperphosphaturia following recent treatment with Ferinject and mild secondary hyperparathyroidism with hypovitaminosis D (PTH 9.5 pmol/L, 250HVitD 12.3 ng/L) were diagnosed in an outpatient follow-up. |
Summary and recommendation
Patients who receive repeated higher doses of parenteral iron in the course of long-term treatment and have underlying risk factors (e.g. vitamin D deficiency, calcium and phosphate malabsorption, secondary hyperparathyroidism, hereditary haemorrhagic telangiectasia, inflammatory bowel disease and osteoporosis) should be monitored for hypophosphataemic osteomalacia, including control of serum phosphate levels. In the case of persistent hypophosphataemia, treatment with parenteral iron should be re-evaluated.
In the case of arthralgia or bone pain, the patient should be advised to seek medical advice.
Electronic reports via the ElVis portal