Hypercalcemia in Cats: Recognizing and Managing Elevated Calcium Levels

Hypercalcemia - elevated blood calcium - is a relatively common finding in cats with multiple potential causes, from dietary issues to cancer. It causes significant welfare impacts when left undiagnosed.

Key Facts

Hypercalcemia is the most common electrolyte abnormality found in cats at specialty practices
Idiopathic hypercalcemia is the most frequent cause in cats (no identifiable cause found)
Other causes include lymphoma, vitamin D toxicity, primary hyperparathyroidism, and chronic kidney disease
Symptoms include lethargy, decreased appetite, vomiting, increased thirst and urination
Chronic hypercalcemia causes calcium deposits in kidneys, leading to progressive kidney damage
Dietary management with hydrolyzed protein or fiber-rich diets can help idiopathic cases
Regular monitoring of calcium and kidney values is essential for affected cats

Welfare Considerations

Cats with hypercalcemia often suffer silently - the gradual onset of symptoms is easily attributed to aging or stress. Nausea, lethargy, and decreased appetite significantly reduce quality of life. The insidious development of kidney mineralization can lead to irreversible chronic kidney disease if hypercalcemia goes untreated. The frustrating reality is that many cats improve significantly with treatment, meaning delayed diagnosis translates to months or years of preventable suffering. Annual blood panels in adult cats are the most effective welfare intervention.

What You Can Do

Include calcium measurement in annual wellness blood panels for cats over 7 years
Monitor for subtle signs: reduced appetite, increased drinking, lethargy
If hypercalcemia is confirmed, work with your vet to find the underlying cause
Discuss dietary trials for idiopathic hypercalcemia before pursuing more invasive diagnostics
Ensure affected cats have excellent water access to support kidney health
Follow up with regular calcium and kidney function monitoring every 3-6 months