What the parathyroid glands do
Four small glands behind the thyroid make parathyroid hormone (PTH), which controls blood calcium. In primary hyperparathyroidism, usually one gland becomes overactive.
Symptoms
Many people have none. Others notice:
- Kidney stones
- Bone thinning or fractures
- Tiredness, thirst and passing more urine
- Constipation, low mood or poor concentration
Tests
- Calcium (adjusted for albumin), PTH, phosphate and vitamin D
- Kidney function and urine calcium
- A bone density scan, and kidney imaging for stones
Scans to find the overactive gland are done only after the diagnosis is confirmed and surgery is being planned.
Other causes of high calcium
Too much vitamin D, some medicines such as certain diuretics, dehydration, an overactive thyroid, and some cancers and inflammatory conditions. This is why the full picture matters.
Treatment
Surgery to remove the overactive gland is the only cure. It is advised for people with symptoms, kidney stones, osteoporosis, a markedly high calcium, reduced kidney function or age under 50. Others can be monitored.
About kidney stones
Most stones are not caused by hormones, but recurrent stones deserve a metabolic check. Drink enough water, and do not cut normal dietary calcium unless advised.
This guide is for general educational purposes and does not replace individual medical advice, diagnosis or treatment. Consult your doctor for advice specific to your health.