• Cancer involving bone (carcinoma of breast, bronchus, renal, thyroid, and prostate); haematological cancer, for example myeloma and lymphoma. Mechanisms: secretion of parathyroid-hormone-related protein; bone metastases; increased production of 1,25-dihydroxy vitamin D; ectopic parathyroid hormone production.
• Primary hyperparathyroidism.
• Chronic kidney disease with tertiary hyperparathyroidism and treatment with calcium and vitamin D metabolites.

Uncommon

• Sarcoidosis and other granulomatous diseases such as tuberculosis
• Other cancers with humoural effects (see above)
• Thyrotoxicosis
• Vitamin D excess
• Milk-alkali syndrome
• Adrenal insufficiency
• Paget's disease with immobilization
• Acromegaly
• HIV infection
• Vitamin A toxicity
• Drugs, for example thiazides, lithium therapy
• Hypocalciuric hypercalcaemia