Causes and Treatment for Increased Blood Calcium Levels (Hypercalcemia) in Dogs
Primary hyperparathyroidism
Parathyroid glands are overactive
(often due to a tumor) and secrete excess parathyroid hormone
Removal or destruction of tumor
Hypercalcemia caused by cancer
(Malignant hypercalcemia)
Increased bone breakdown and resorption triggered by cancer cells causes higher levels of calcium in blood
Depends on specific type of cancer
Chronic kidney failure
Exact mechanism is unknown
Vitamin D toxicity
(hypervitaminosis D)
Vitamin D supplements taken in excess
(e.g., to treat hypoparathyroidism); accidental ingestion of human psoriasis medicine or rodent poisons containing calcitriol
Adjustment of vitamin D dosage
(if from medication)
Granulomatous disease
Inflammation activates type of white blood cells that can increase levels of active vitamin D
Treatment of underlying disease,
(e.g., antifungal drugs or surgery)