Can I take Promethazine and Vitamin d3 together?
Drug interaction guide
Originally published 25 Jan 2026
Meets Patient’s editorial guidelines
- DownloadDownload
- Share
- Language
- Discussion
There are no known significant interactions between promethazine and vitamin D3 (cholecalciferol). It is generally considered safe to take these two medications together.
In this article:
Continue reading below
Why this happens
Promethazine is an antihistamine processed primarily by the liver's cytochrome P450 enzymes, while vitamin D3 is a fat-soluble vitamin that undergoes a different metabolic pathway (hydroxylation in the liver and kidneys). They do not interfere with each other's absorption, metabolism, or effects in the body.
What you should do
Back to contentsYou can continue to take both medications as prescribed. As with any supplement, it is best to take vitamin D3 with a meal containing some fat to help with absorption. Promethazine can cause drowsiness, so be aware of how it affects you before driving or operating machinery.
Continue reading below
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.
Patient picks for Drug interactions

Treatment and medication
Can I take Alcohol and Citalopram together?
Drinking alcohol while taking citalopram can make you feel much more drowsy, dizzy, or sleepy than usual. It can also impair your coordination, reaction times, and judgement. Additionally, alcohol can worsen the symptoms of depression or anxiety that the citalopram is meant to treat, potentially making the medication less effective over time.

Treatment and medication
Can I take Atorvastatin and Prednisolone together?
Taking atorvastatin and prednisolone together may increase the risk of muscle-related side effects, such as muscle pain, tenderness, or weakness. In rare cases, this can lead to a serious condition called rhabdomyolysis, where muscle tissue breaks down and can cause kidney damage. Additionally, prednisolone can raise blood sugar levels, which may slightly reduce the effectiveness of atorvastatin in managing your cholesterol profile.
Continue reading below
Article history
The information on this page is written and peer reviewed by qualified clinicians.
25 Jan 2026 | Originally published

Ask, share, connect.
Browse discussions, ask questions, and share experiences across hundreds of health topics.

Feeling unwell?
Assess your symptoms online for free
Sign up to the Patient newsletter
Your weekly dose of clear, trustworthy health advice - written to help you feel informed, confident and in control.
By subscribing you accept our Privacy Policy. You can unsubscribe at any time. We never sell your data.