Can I take Vitamin b12 and Vitamin d3 together?
Drug interaction guide
Originally published 14 Mar 2026
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There is no known negative interaction between Vitamin B12 (cyanocobalamin/methylcobalamin) and Vitamin D3 (cholecalciferol). In fact, these two vitamins are often taken together to support overall health.
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Why this happens
Vitamin B12 and Vitamin D3 use different pathways for absorption and metabolism in the body. Vitamin B12 is a water-soluble vitamin absorbed primarily in the small intestine with the help of a protein called intrinsic factor. Vitamin D3 is a fat-soluble vitamin that requires dietary fat for optimal absorption. Because they do not compete for the same transport systems or metabolic enzymes, they do not interfere with one another.
What you should do
Back to contentsIt is safe to take Vitamin B12 and Vitamin D3 at the same time. To get the most benefit, take Vitamin D3 with a meal containing some fat (like yoghurt, eggs, or avocado) to help your body absorb it. You should always follow the dosage instructions on the label or those provided by your healthcare professional.
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Using other medicines
Back to contentsTaking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.
Disclaimer
This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.
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Taking fluoxetine with Abilify (aripiprazole) can significantly increase the amount of Abilify in your bloodstream. This makes you much more likely to experience side effects such as extreme sleepiness, restlessness (feeling like you cannot sit still), uncontrollable body movements (tremors or twitching), and dizziness. There is also a small but serious risk of a heart rhythm problem called QT prolongation.
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Article history
The information on this page is written and peer reviewed by qualified clinicians.
14 Mar 2026 | Originally published

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