How do you increase parathyroid hormone (PTH) levels?

Methods to Increase Parathyroid Hormone (PTH) Levels

To increase parathyroid hormone (PTH) levels, the most effective approach is to reduce serum calcium and vitamin D levels through dietary restriction, medication adjustments, or specific therapeutic interventions targeting the calcium-PTH feedback loop. 1, 2

Understanding PTH Regulation

• PTH secretion is primarily regulated by serum calcium levels through a negative feedback mechanism - low calcium stimulates PTH secretion while high calcium suppresses it 3
• Vitamin D (particularly 1,25-dihydroxyvitamin D) has a suppressive effect on PTH synthesis and secretion; therefore, low vitamin D levels can lead to increased PTH 2
• Phosphorus levels also affect PTH - high phosphorus stimulates PTH secretion 1

Strategies to Increase PTH Levels

Calcium Management

• Reduce calcium intake through dietary restriction of calcium-rich foods 2
• If on calcium supplements, consider reducing or temporarily discontinuing them under medical supervision 2
• For patients on active vitamin D therapy, reducing or holding the dose can help increase PTH levels 1
• In patients with CKD, if PTH levels are below target range, active vitamin D therapy should be reduced or temporarily discontinued until PTH rises above the target range 1

Vitamin D Management

• Reduce or temporarily discontinue vitamin D supplementation, particularly active vitamin D sterols (calcitriol, alfacalcidol, paricalcitol, or doxercalciferol) 1
• In patients with chronic kidney disease, reducing active vitamin D doses can allow PTH levels to increase 1
• Monitor vitamin D levels, as severe vitamin D deficiency can lead to secondary hyperparathyroidism, which may not be the desired outcome 4, 5

Phosphate Management

• Increasing serum phosphorus levels can stimulate PTH secretion 1
• In patients with CKD, if phosphorus levels are below 4.6 mg/dL, consider adjusting phosphate binders to allow phosphorus levels to rise slightly 1
• Phosphate supplements may be considered in some cases, but should be used with caution due to potential adverse effects 1

Pharmacological Approaches

• Calcimimetics (like cinacalcet) should be reduced or discontinued if being used, as they suppress PTH secretion 1
• Teriparatide (recombinant human PTH 1-34) can be administered as a direct replacement, but is typically used for osteoporosis treatment rather than to increase endogenous PTH 6

Monitoring and Safety Considerations

• Regular monitoring of serum calcium, phosphorus, and PTH levels is essential when attempting to increase PTH 1
• Monitor for symptoms of hypocalcemia (muscle cramps, paresthesias, seizures) if actively reducing calcium levels 2
• In patients with CKD, PTH targets vary by disease stage - avoid excessive PTH elevation which can lead to bone disease 1
• Patients with vitamin D deficiency may require careful monitoring as PTH levels may rise excessively 4, 5

Special Considerations

• In patients with X-linked hypophosphataemia, reducing active vitamin D and increasing phosphate supplements may increase PTH 1
• For patients with primary hyperparathyroidism, vitamin D supplementation may actually decrease PTH levels and should be avoided if the goal is to increase PTH 7, 8
• In patients with chronic kidney disease, the target PTH range varies by CKD stage, with higher targets (150-300 pg/mL) for dialysis patients 1

Cautions

• Deliberately increasing PTH levels may have negative consequences on bone health and cardiovascular risk 1
• Sustained elevation of PTH can lead to hyperparathyroid bone disease and increased bone turnover 1
• Any intervention to increase PTH should be performed under close medical supervision with regular monitoring 1