Hyperphosphatemia is when excessive levels of phosphates are present in the blood and often occurs as a result of improperly functioning kidneys. Other possible causes include cell damage, high vitamin D levels, diabetic ketoacidosis, muscle injuries, serious infection, and hypoparathyroidism. 

Symptoms of hyperphosphatemia include high levels of the parathyroid hormone (which regulates calcium levels in the blood), low levels of calcium, muscle cramps or spasms, rash, itchy skin, numbness around the mouth, and bone or joint pain. High phosphorus levels increase the risk of bone and heart diseases.   

Treatment of hyperphosphatemia usually involves lowering phosphate levels by making dietary changes and taking medication. Foods high in phosphorus include red meat, milk, poultry, fish, and eggs. In severe cases, extra phosphates may be removed with dialysis. Drugs used to treat hyperphosphatemia include mineral binding agents, such as calcium acetate or sevelamer carbonate.