Drug interactions
Cholecalciferol + Phenobarbital
Severity: Moderate
Cholecalciferol and Phenobarbital: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Chronic phenobarbital therapy accelerates vitamin D metabolism and may lead to deficiency, osteomalacia and reduced bone density.
What this interaction means in plain words
Cholecalciferol and Phenobarbital can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Phenobarbital induces hepatic CYP enzymes, increasing the catabolism of vitamin D.
What to do
Monitor 25-hydroxyvitamin D, calcium and bone health in long-term users. Supplement vitamin D at higher doses if deficient.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Cholecalciferol
- Cholecalciferol + Digoxin Major
- Aluminum hydroxide + Cholecalciferol Moderate
- Calcium acetate + Cholecalciferol Moderate
- Calcium Carbonate + Cholecalciferol Moderate
- Calcium chloride + Cholecalciferol Moderate
- Calcium citrate + Cholecalciferol Moderate
Frequently asked questions
Can I take Cholecalciferol with Phenobarbital?
MediHelp rates the interaction as moderate. Cholecalciferol and Phenobarbital can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Chronic phenobarbital therapy accelerates vitamin D metabolism and may lead to deficiency, osteomalacia and reduced bone density.
How serious is the interaction between Cholecalciferol and Phenobarbital?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor 25-hydroxyvitamin D, calcium and bone health in long-term users. Supplement vitamin D at higher doses if deficient.
What other medicines interact with Cholecalciferol?
MediHelp also lists interactions of Cholecalciferol with, for example, Digoxin, Aluminum hydroxide, Calcium acetate. The full list is on the Cholecalciferol page.
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