Supplement stacks / Calcium + Phenytoin
Can You Take Calcium with Phenytoin?
Calcium and Phenytoin: 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 calcium with phenytoin may lead to reduced absorption of phenytoin, potentially affecting its efficacy. It is important to monitor levels and consult a healthcare provider for personalized advice.
Phenytoin 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 may interfere with the absorption of phenytoin, potentially reducing its effectiveness. It is advisable to separate the intake of these substances by at least 2 hours.
Calcium
From the AI-written analysis.
Calcium is generally safe when taken as directed, but excessive intake can lead to hypercalcemia and other complications. Consult a healthcare provider for personalized advice, especially when on phenytoin.
Typical dosage: Varies by product — follow the label.
- Constipation
- Nausea
- Stomach upset
- Consult a healthcare provider if taking phenytoin; monitor for signs of hypercalcemia.
Phenytoin
From the AI-written analysis.
Phenytoin has a narrow therapeutic index, and its levels can be affected by various factors, including dietary supplements like calcium. Regular monitoring is essential.
Typical dosage: As prescribed or as directed on the label
- Dizziness
- Drowsiness
- Gingival hyperplasia
- Monitor phenytoin levels regularly; consult a healthcare provider for any changes in health status.
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.
Frequently asked questions
Can you take Calcium and Phenytoin together?
Calcium and Phenytoin: 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 Phenytoin combination get?
The Calcium and Phenytoin 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 Phenytoin?
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.
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Not medical advice
AI-written analysis generated August 28, 2026, checked by our interaction rules · How our analysis works