Interaction guide

Calcium and thyroid medication spacing

Calcium supplements can reduce levothyroxine absorption when they share the same dosing window, making timing consistency part of the medication plan.

Default spacing rule

Keep calcium supplements at least 4 hours away from levothyroxine unless the prescribing clinician gives a different plan.

Interaction map

Calcium and thyroid medication spacing: the decision path

Check these

Calcium carbonateCalcium citrateMineral multivitaminsLevothyroxineThyroid-medication routines

Default action

Keep calcium supplements at least 4 hours away from levothyroxine unless the prescribing clinician gives a different plan.

Why it matters

Reduced medication absorptionConfusing thyroid-lab follow-upHidden calcium from multis or fortified products

Products to check

  • Calcium carbonate
  • Calcium citrate
  • Mineral multivitamins
  • Levothyroxine
  • Thyroid-medication routines

Why it matters

  • Reduced medication absorption
  • Confusing thyroid-lab follow-up
  • Hidden calcium from multis or fortified products

Sources and related pages

Mayo Clinic levothyroxine and calcium timing guidanceSingh et al. calcium carbonate and levothyroxine absorptionCalcium monographStack timing plannerSafety alert topic hub

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These statements have not been evaluated by the FDA. Not intended to diagnose, treat, cure, or prevent any disease. Generated by AI. Always verify with a healthcare professional. Educational information only. Not a substitute for professional medical advice.