SLOT: Full Definition
What is hyperparathyroidism?
Hyperparathyroidism — sometimes called overactive parathyroid or HPT — is a condition in which one or more of the four small parathyroid glands behind the thyroid produce too much parathyroid hormone (PTH). PTH controls calcium balance; when it is too high, calcium is pulled out of bones into the bloodstream, leading to a constellation of symptoms classically summarized as "stones, bones, abdominal groans, and psychic moans."
Many women are surprised to learn this isn't a thyroid problem. The parathyroid glands sit on the back of the thyroid but have an entirely different job. Hyperparathyroidism is more common in women, especially after menopause, and often hides behind a slightly high calcium level on a routine blood test.
What causes hyperparathyroidism?
There are three categories:
- Primary hyperparathyroidism — usually a benign tumor (parathyroid adenoma) on one gland; less commonly hyperplasia of multiple glands or, rarely, parathyroid cancer
- Secondary hyperparathyroidism — the parathyroids overproduce PTH in response to low calcium or vitamin D, often in chronic kidney disease
- Tertiary hyperparathyroidism — long-standing secondary disease leading to autonomous PTH overproduction
Genetics, prior neck radiation, and certain medications can also play a role.
How is hyperparathyroidism diagnosed?
The classic lab pattern is high blood calcium with an inappropriately high or normal PTH. Workup typically includes calcium, PTH, ionized calcium, vitamin D (25-OH), phosphorus, magnesium, and a 24-hour urine calcium. Bone density (DEXA) and kidney imaging help assess complications. Imaging of the parathyroids (sestamibi scan, neck ultrasound, or 4D-CT) is used to localize the overactive gland before surgery.
At Modern Thyroid Clinic we frequently catch this pattern when reviewing labs in women who came in for thyroid concerns and happen to have a creeping high calcium that no one had explained.
How is hyperparathyroidism treated?
The definitive treatment for primary hyperparathyroidism is parathyroidectomy — surgical removal of the overactive gland or glands by an experienced parathyroid surgeon. Surgery resolves the disease in most cases and prevents long-term bone loss and kidney stones. Mild, asymptomatic disease in older patients may be monitored. Secondary hyperparathyroidism is treated by addressing the underlying cause (vitamin D deficiency, kidney disease).
Hyperparathyroidism is not treated at Modern Thyroid Clinic — it requires referral to endocrine surgery — but we routinely identify it, ensure proper workup, and support patients through evaluation and recovery.
Common symptoms
Common questions
How is this different from a thyroid problem?
The parathyroid glands sit on the back of the thyroid but are completely separate organs with a different job: regulating calcium. Thyroid disease affects metabolism, energy, weight, and temperature regulation. Parathyroid disease affects calcium, bones, kidneys, and cognition. It's possible to have both, but they are diagnosed and treated very differently. A high calcium on routine labs almost always points to the parathyroids, not the thyroid.
Can hyperparathyroidism cause [fatigue] and brain fog?
Yes — and these are some of the most under-recognized symptoms. Persistent fatigue, [brain-fog], depression, irritability, sleep disturbance, bone aches, and muscle weakness are all common. Because they're nonspecific, they often get blamed on aging, perimenopause, or stress for years before the calcium connection is made. Many women report a dramatic energy and mental-clarity boost after parathyroidectomy.
Do I need surgery if I feel fine?
Even "asymptomatic" hyperparathyroidism can quietly cause bone loss, kidney stones, and cardiovascular changes. Surgery is generally recommended if calcium is significantly elevated, bone density is low, kidney function is affected, you're under 50, or you have any classic symptoms. A careful conversation with an experienced endocrine surgeon will weigh your specific risks and benefits.
Think you might be dealing with this?
Talk to a Modern Thyroid Clinic specialist about your symptoms, labs, and next steps.
Book a Discovery CallThis content is for educational purposes only and is not medical advice. Consult a licensed clinician for diagnosis and treatment. Content on this page does not create a doctor-patient relationship with Modern Thyroid Clinic.