NSTK · 01.2026Independent supplement reference
NutriStack
Edition 1.0Reviewed May 26, 2026

Nutrient depletion·Calcium·Reviewed June 9, 2026

What depletes calcium?

24 medications in the NutriStack database are documented to lower Calcium with ongoing use, most notably Carbamazepine, Cinacalcet, Dexamethasone, and Methylprednisolone. The pattern spans 13 drug classes. Another 4 bind calcium in the gut when taken at the same time, which is a timing problem rather than true depletion. Depletion builds slowly and is easy to miss; the table below shows how each medication drives it and which biomarker to check. Never start a replacement supplement without your prescriber's input.

In short

Calcium depletion at a glance.

A quick, data-grounded summary. The per-medication table is below.

24 medications in the NutriStack database are documented to lower Calcium with ongoing use, most notably Carbamazepine, Cinacalcet, Dexamethasone, and Methylprednisolone. The pattern spans 13 drug classes. Another 4 bind calcium in the gut when taken at the same time, which is a timing problem rather than true depletion. Depletion builds slowly and is easy to miss; the table below shows how each medication drives it and which biomarker to check. Never start a replacement supplement without your prescriber's input.

Medications

What is documented to lower calcium.

Worst documented severity first. Open any medication for its full interaction and depletion guide. Absence from this table means no documented record, not proven safety.

MedicationSeverityHow it lowers calciumMonitor
Carbamazepine
Antiepileptic
SignificantReduced vitamin D activity and chronic anticonvulsant use lower calcium balance and bone density.Serum calcium or bone density trend
Cinacalcet
Calcimimetic calcium-sensing receptor agonist
SignificantCinacalcet intentionally lowers PTH and serum calcium and can cause clinically significant hypocalcemia.Corrected serum calcium
Dexamethasone
Corticosteroid
SignificantGlucocorticoids reduce intestinal calcium absorption, increase urinary calcium loss, and accelerate bone resorption.Serum calcium or bone density trend
Methylprednisolone
Corticosteroid
SignificantGlucocorticoids reduce intestinal calcium absorption, increase urinary calcium loss, and accelerate bone resorption.Serum calcium or bone density trend
Phenytoin
Antiepileptic
SignificantReduced vitamin D activity and chronic anticonvulsant use lower calcium balance and bone mineral density.Serum calcium or bone density trend
Prednisolone
Corticosteroid
SignificantGlucocorticoids reduce intestinal calcium absorption, increase urinary calcium loss, and accelerate bone resorption.Serum calcium or bone density trend
Prednisone
Corticosteroid
SignificantGlucocorticoids reduce intestinal calcium absorption, increase urinary calcium loss, and accelerate bone resorption.Serum calcium or bone density trend
Zoledronic Acid
Bisphosphonate
SignificantPotent IV bisphosphonate therapy can acutely suppress bone resorption and lower serum calcium, especially with low vitamin D status or kidney...Serum calcium + 25-OH vitamin D
Alendronate
Bisphosphonate
ModerateBisphosphonate suppression of bone resorption can lower serum calcium, especially when calcium intake, vitamin D status, or kidney function is poor.Serum calcium + 25-OH vitamin D
Esomeprazole
Proton Pump Inhibitor
ModerateLower gastric acidity reduces dissolution and absorption of less-soluble calcium salts, especially calcium carbonate.Serum calcium or bone density trend
Furosemide
Loop Diuretic
ModerateLoop diuretics reduce calcium reabsorption in the thick ascending limb, increasing urinary calcium loss.Serum calcium
Lansoprazole
Proton Pump Inhibitor
ModerateLower gastric acidity reduces dissolution and absorption of less-soluble calcium salts, especially calcium carbonate.Serum calcium or bone density trend
Omeprazole
Proton Pump Inhibitor
ModerateLower gastric acidity reduces dissolution and absorption of less-soluble calcium salts, especially calcium carbonate.Serum calcium or bone density trend
Pantoprazole
Proton Pump Inhibitor
ModerateLower gastric acidity reduces dissolution and absorption of less-soluble calcium salts, especially calcium carbonate.Serum calcium or bone density trend
Phenobarbital
Barbiturate anticonvulsant
ModerateReduced vitamin D activity decreases intestinal calcium absorption and can contribute to secondary hyperparathyroidism and bone loss.Serum calcium, parathyroid hormone, and bone density when indicated
Primidone
Anticonvulsant metabolized to phenobarbital
ModerateLower vitamin D activity reduces intestinal calcium absorption and can contribute to bone loss.Serum calcium, parathyroid hormone, and bone density when indicated
Risedronate
Bisphosphonate
ModerateBisphosphonate suppression of bone resorption can lower serum calcium, especially when calcium intake, vitamin D status, or kidney function is poor.Serum calcium + 25-OH vitamin D
Valproic Acid
Mood Stabilizer / Anticonvulsant
ModerateLong-term valproate therapy is associated with lower bone mineral density and poorer calcium balance.Serum calcium or bone density trend
Budesonide Inhaled
Inhaled Corticosteroid
MildLong-term or high-dose inhaled corticosteroid exposure can reduce bone formation and contribute to poorer calcium balance.Bone density trend + serum calcium when indicated
Fluticasone Inhaled
Inhaled Corticosteroid
MildLong-term or high-dose inhaled corticosteroid exposure can reduce bone formation and contribute to poorer calcium balance.Bone density trend + serum calcium when indicated
Rabeprazole
Proton pump inhibitor
MildAcid suppression may reduce absorption of some calcium salts and is associated with fracture risk during high-dose or long-term therapy.25-hydroxyvitamin D, calcium intake assessment, bone density when indicated
Rifampin
Rifamycin Antibiotic
MildRifampin lowers active vitamin D metabolites through PXR-mediated CYP induction, which secondarily reduces intestinal calcium absorption. Chronic...Serum calcium and serum 25-hydroxyvitamin D
Tenofovir Disoproxil
Nucleotide reverse-transcriptase inhibitor (NRTI)
MildRenal phosphate wasting, reduced active vitamin D, and secondary hyperparathyroidism increase bone turnover and urinary calcium losses; proximal...Serum calcium, 24-hour urinary calcium, parathyroid hormone (PTH), bone mineral density (DXA)
Topiramate
Antiepileptic
MildTopiramate therapy has been associated with changes in bone and mineral metabolism, including lower calcium status markers in some patients.Serum calcium + 25-OH vitamin D + bone density trend
Timing conflicts

Binds calcium, not depletion.

These medications form poorly absorbed complexes with calcium in the gut when doses overlap. That blunts absorption of the medication, the mineral, or both at that dose, but it does not drain the body's stores. The fix is separating doses by the window on each medication's page, not supplementing more.

MedicationSeverityWhat happens when taken togetherMonitor
Doxycycline
Tetracycline Antibiotic
MildTetracyclines chelate divalent minerals in the gut, functionally reducing calcium availability during active treatment when taken together.Clinical assessment
Minocycline
Tetracycline antibiotic
MildMinocycline forms insoluble chelate complexes with divalent and trivalent cations including calcium. This bidirectional chelation reduces absorption...Serum calcium (rarely needed for short courses); clinical assessment usually sufficient
Moxifloxacin
Fluoroquinolone antibiotic
MildCalcium ions chelate moxifloxacin in the gut, forming poorly absorbed complexes. The primary clinical consequence is reduced antibiotic...Serum calcium (routine monitoring not generally required)
Tetracycline
Tetracycline antibiotic
MildTetracycline chelates divalent and trivalent cations, forming insoluble, poorly absorbed complexes with calcium in the gut. Concurrent intake...Serum calcium (ionized or albumin-corrected)
Replacing it

If you need to restore calcium.

Repletion is not automatic: dose, form, and timing depend on the medication involved, and some pairings need separation from the very drug causing the depletion. Confirm with your prescriber before adding calcium.

FAQ

Common calcium depletion questions.

Quick answers drawn from the table above.

Which medications deplete calcium?

24 medications in the NutriStack database are documented to lower calcium, including Carbamazepine, Cinacalcet, Dexamethasone, Methylprednisolone, and Phenytoin. Severity differs by drug; the full table with mechanisms and monitoring biomarkers is on this page.

How do I know if my calcium is low?

The biomarkers used to track calcium status in this context include Serum calcium or bone density trend, Corrected serum calcium, and Serum calcium + 25-OH vitamin D. If you take one of the medications above long term, ask your prescriber whether checking is worthwhile; depletion develops gradually.

Should I take a calcium supplement with these medications?

Not automatically. Documented depletion makes repletion worth discussing, but the right answer depends on your labs, dose, and the specific drug, and some pairings need calcium doses separated from the medication itself. Bring it up with your prescriber or pharmacist.

Check your whole stack

See what your medications deplete.

NutriStack screens your full routine for interactions and depletions, and updates the moment you change it.

NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.