Supplement stacks / Biotin + Levothyroxine
Can You Take Biotin with Levothyroxine?
Biotin and Levothyroxine: one interaction flagged, scored 6/10 (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
Biotin supplementation may not significantly interfere with levothyroxine absorption, but caution is advised due to limited evidence on interactions. It is recommended to consult a healthcare provider before combining these substances.
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
Biotin
From the AI-written analysis.
Generally considered safe at recommended dosages; high doses may lead to skin rashes or gastrointestinal upset.
Typical dosage: 30-100 mcg daily
- Skin rash
- Gastrointestinal upset
- Consult healthcare provider if taking thyroid medications; monitor thyroid function tests.
Levothyroxine
From the AI-written analysis.
Safe when taken as prescribed; overdose can lead to hyperthyroidism symptoms.
Typical dosage: As prescribed or as directed on the label
- Weight loss
- Increased heart rate
- Nervousness
- Take on an empty stomach; avoid calcium and iron supplements within 4 hours.
Also commonly mentioned
These come up in questions about this combination. They are not part of the pair above. From the AI-written analysis.
Vitamin D3
Generally safe; excessive doses can lead to toxicity.
Typical dosage: 600-2000 IU daily, depending on individual needs
- Nausea
- Vomiting
- Weakness
- Monitor blood levels if taking high doses; consult healthcare provider.
Magnesium
Safe at recommended dosages; excessive intake can cause diarrhea.
Typical dosage: 310-420 mg daily, depending on age and sex
- Diarrhea
- Nausea
- May interfere with levothyroxine absorption; take at least 4 hours apart.
Zinc
Generally safe; high doses can cause nausea and immune dysfunction.
Typical dosage: 8-11 mg daily
- Nausea
- Diarrhea
- May interfere with levothyroxine absorption; take at least 4 hours apart.
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.
Recommendations
- Consult with a healthcare provider before starting biotin or any new supplement.
- Consider spacing biotin and levothyroxine doses to minimize potential interactions.
Watch out for
- Monitor thyroid function tests regularly if taking biotin.
- Take levothyroxine on an empty stomach and avoid taking it with biotin or other supplements that may interfere.
Frequently asked questions
Can you take Biotin and Levothyroxine together?
Biotin and Levothyroxine: one interaction flagged, scored 6/10 (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 Biotin and Levothyroxine combination get?
The Biotin and Levothyroxine combination is scored 6/10 (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 Biotin 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 Biotin and Levothyroxine?
Monitor thyroid function tests regularly if taking biotin. Take levothyroxine on an empty stomach and avoid taking it with biotin or other supplements that may interfere.
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Not medical advice
AI-written analysis generated August 10, 2026, checked by our interaction rules · How our analysis works