Supplement stacks / Calcium + Levothyroxine
Can You Take Calcium with Levothyroxine?
Calcium and Levothyroxine: one interaction flagged, scored 5/10 (medium risk). The count and score come from an AI-written analysis checked against our interaction rules, which can only make it stricter. Not medical advice.
Safety at a glance
This score comes from an AI-written analysis of the pair. Our interaction rules check it and can only make it stricter, never milder. Informational only: it can't account for your medications, conditions, or genetics.
What the AI-written analysis says
Taking Levothyroxine with Calcium can lead to reduced absorption of Levothyroxine, potentially impacting thyroid hormone levels. It is advisable to separate their intake to minimize this risk.
Levothyroxine is a prescription medication. This page describes publicly documented interactions — it can't see your dose, your other prescriptions, or your labs. Discuss any supplement with the prescriber or pharmacist who manages this medication before combining.
Known interactions
Calcium can interfere with the absorption of Levothyroxine, potentially leading to decreased effectiveness of the thyroid medication.
Calcium
From the AI-written analysis.
Generally safe; excessive intake can lead to hypercalcemia.
Typical dosage: Follow manufacturer guidelines; often 1000-1200 mg/day.
- Constipation
- Stomach upset
- Kidney stones (with high doses)
- Consult healthcare provider if taking other medications
- Monitor calcium levels if on long-term supplementation
Levothyroxine
From the AI-written analysis.
Generally safe when taken as prescribed; monitor thyroid levels regularly.
Typical dosage: As prescribed or as directed on the label
- Weight changes
- Increased heart rate
- Nervousness
- Consult healthcare provider for dosage adjustments
- Monitor for signs of overmedication
Timing
Take as prescribed — we do not schedule prescription medications. Follow the label or your prescriber, and ask your pharmacist before changing when you take it.
Watch out for
- Calcium, iron, magnesium, chromium, fibre supplements and antacids can lower how much thyroid medication (levothyroxine) is absorbed, which can leave your thyroid under-treated. Keep at least 4 hours between them. Prescribing information has levothyroxine taken on an empty stomach, typically 30-60 minutes before breakfast, so the mineral, fibre supplement, antacid or multivitamin is the one that fits later in the day; follow your prescriber or pharmacist on the levothyroxine itself. Ask for a TSH recheck if you start or change the mineral, the fibre supplement or the antacid.
Frequently asked questions
Can you take Calcium and Levothyroxine together?
Calcium and Levothyroxine: one interaction flagged, scored 5/10 (medium risk). The count and score come from an AI-written analysis checked against our interaction rules, which can only make it stricter. Not medical advice.
What score does the Calcium and Levothyroxine combination get?
The Calcium and Levothyroxine combination is scored 5/10 (medium risk). The score comes from an AI-written analysis checked against our interaction rules, which can only make it stricter. Not medical advice. Always confirm with a healthcare professional.
When should you take Calcium and Levothyroxine?
Take as prescribed — we do not schedule prescription medications. Follow the label or your prescriber, and ask your pharmacist before changing when you take it.
What should you watch out for when combining Calcium and Levothyroxine?
Calcium, iron, magnesium, chromium, fibre supplements and antacids can lower how much thyroid medication (levothyroxine) is absorbed, which can leave your thyroid under-treated. Keep at least 4 hours between them. Prescribing information has levothyroxine taken on an empty stomach, typically 30-60 minutes before breakfast, so the mineral, fibre supplement, antacid or multivitamin is the one that fits later in the day; follow your prescriber or pharmacist on the levothyroxine itself. Ask for a TSH recheck if you start or change the mineral, the fibre supplement or the antacid.
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Not medical advice
AI-written analysis generated September 5, 2026, checked by our interaction rules · How our analysis works