What Should You Not Take With Vitamin D? The NHS List

The NHS names seven groups of medicines to tell your doctor about before taking vitamin D: digoxin, some diuretics (bendroflumethiazide, indapamide), epilepsy medicines, paraffin oil and cholestyramine, steroids, some antifungals and actinomycin, and it says not to take any other supplement containing calcium or vitamin D without asking first.¹ Diltiazem, verapamil, statins, levothyroxine, sertraline and carbimazole are not on the NHS, BNF or NICE lists. Magnesium, calcium, K2, B12 and iron can be taken alongside it. Add up the vitamin D in everything you take against the NHS ceiling of 100 micrograms (4,000 IU) a day, and keep to 10 micrograms unless a doctor has prescribed more.² Part of the vitamin D guide and the vitamins and minerals guide.

Which medicines does the NHS say to tell your doctor about before taking vitamin D?

The NHS colecalciferol page (prescription vitamin D3) says "Tell your doctor if you (or your child) are taking any of these medicines before you start taking colecalciferol". Its seven bullets, verbatim:¹

The page adds: "Do not take any other vitamin or mineral supplements that contain calcium or vitamin D without talking to your doctor first" and "There's not enough information to say whether other complementary medicines, herbal remedies and supplements are safe to take with colecalciferol."¹ NICE adds orlistat: "vitamin D preparations should be taken at least 2 hours after taking orlistat, or at bedtime".^{3, 4} The BNF table for ergocalciferol (vitamin D2) names the same medicines; the NHS says "All types of vitamin D work in this way".^{5, 6}

Can I take vitamin D with diltiazem or verapamil?

Diltiazem and verapamil are not on the NHS lists: the NHS pages for both do not name vitamin D, calcium or magnesium, and the BNF vitamin D tables do not list either drug.^{3, 5, 7, 8} One UK manufacturer's product information for a modified-release diltiazem does say that "high doses of Vitamin D and/or high intake of calcium salts leading to elevated serum calcium levels may reduce the response to diltiazem", the same raised-calcium logic as the NHS digoxin and diuretic lines.⁹ Both NHS pages end: "Tell your doctor or pharmacist if you're taking any other medicines, including herbal remedies, vitamins or supplements."^{7, 8} So ask your pharmacist, mentioning the 10 microgram NHS amount.

Can I take vitamin D with statins, blood pressure tablets, thyroid medicine or antidepressants?

Statins (atorvastatin, simvastatin, rosuvastatin) are on none of the UK lists, and no UK source says they block vitamin D; the NHS atorvastatin page names fibrates and St John's wort.¹⁰ Blood pressure tablets: only the thiazide-type diuretics are named on any UK list; amlodipine is not.^{1, 3, 4} Levothyroxine: the NHS names "calcium and iron supplements", not vitamin D; a calcium-and-vitamin D tablet contains calcium, so it falls under that line.¹¹ Sertraline is on no UK vitamin D list.^{1, 3, 4} Carbimazole (the UK name for methimazole): the NHS page names digoxin, warfarin, steroids, black cohosh and biotin, not vitamin D.¹² Ibuprofen and paracetamol are not on the colecalciferol list.¹ Tell your pharmacist anyway.

What cancels out vitamin D absorption?

Vitamin D is fat-soluble, so what blocks fat blocks it. In 17 adolescents on orlistat, vitamin D levels fell within a month despite a 400 IU multivitamin.^{4, 13} Cholestyramine and liquid paraffin are the NHS's "may not enter your blood as usual" pair.¹ "There are no foods or drinks that you need to avoid while taking colecalciferol".⁶ Take tablets or capsules "with your main meal of the day" (NHS); a meal containing fat raised a single dose's peak by about a third in one study.^{14, 15} No trial has compared morning with evening (the best time to take vitamin D).

Can you take vitamin D and magnesium together?

Yes; neither is on the other's lists. The enzymes that handle vitamin D need magnesium, and one randomised trial of 180 US adults aged 40 to 85 found that magnesium raised 25(OH)D3 when baseline 25(OH)D was close to 30 ng/mL and lowered it when baseline was higher, up to 50 ng/mL; the authors concluded that "optimal magnesium status may be important for optimizing 25(OH)D status".¹⁶ That is an interaction, not a rule: no trial shows vitamin D failing without magnesium, and "magnesium activates vitamin D" is not a wording a GB label may use. See what you should not take with magnesium, zinc and magnesium together and magnesium every day.

Can you take vitamin D and calcium together?

Yes, and the fracture trials paired them: six trials of 49,282 people giving 400 to 800 IU of vitamin D with 1,000 to 1,200 mg of calcium a day found 6% fewer fractures (RR 0.94, 95% CI 0.89 to 0.99) and 16% fewer hip fractures (RR 0.84, 0.72 to 0.97), mostly in older adults; eleven trials of vitamin D alone (34,243 people) did not (RR 1.06 and 1.14, neither significant).¹⁷ Adults need 700 mg of calcium a day and "Taking 1,500mg or less a day is unlikely to cause any harm" (NHS); the colecalciferol page asks you not to add another calcium or vitamin D product without asking.^{1, 18} See do you need a calcium supplement.

Do you need K2 with vitamin D?

The one large trial of the pair is null: 365 men aged about 71 with aortic valve calcification took 720 µg of K2 (MK-7) with 25 µg of vitamin D or placebo for two years; "The mean difference on AVC progression was 17 AU (95% CI, -86 to 53 AU; P=0.64)".¹⁹ No trial shows K2 changing a vitamin D outcome, and none shows harm from taking both; the NHS says "Taking 1mg or less of vitamin K supplements a day is unlikely to cause any harm", and anyone on warfarin asks first.²⁰ More at vitamin D3 and K2.

Which supplements add up with vitamin D?

Multivitamins, calcium-and-vitamin D tablets, D3-and-K2 products and cod liver oil all carry vitamin D, as D3 or as vitamin D2 (ergocalciferol); the NHS ceilings apply to the total: "Do not take more than 100 micrograms (4,000 IU) of vitamin D a day as it could be harmful"; "Children aged 1 to 10 years should not have more than 50 micrograms (2,000 IU) a day. Infants under 12 months should not have more than 25 micrograms (1,000 IU) a day."² Contact 111 (NHS) above 4,000 IU in a day for an adult, 2,000 IU for a child aged 1 to 10 and 1,000 IU for a baby.¹⁴ For children: "do not give them cod liver oil and vitamin drops because cod liver oil also contains vitamins A and D".²¹ See can you take too much vitamin D.

Who should ask a pharmacist or doctor before taking vitamin D?

The NHS says to tell your doctor before starting if you have "hypercalcaemia – high levels of calcium in your blood", "hypercalciuria – high levels of calcium in your pee", "problems with your kidneys, such as kidney failure, or you've ever had kidney stones", "hypervitaminosis D – high levels of vitamin D in your blood", "a rare condition called sarcoidosis", "calcification – high levels of calcium in your body tissues or organs" or "a peanut or soya allergy".²² A heart condition on its own is on neither list; the medicines digoxin and the thiazide-type diuretics are.

Frequently asked questions

What 4 supplements should you not mix with vitamin D?

None is dangerous with it. The four worth counting also contain vitamin D: a multivitamin, a calcium-and-vitamin D tablet, a D3-and-K2 product and cod liver oil, which together can pass 100 µg.²

What should you never mix with vitamin D?

The NHS has no "never" list: seven medicine groups to tell your doctor about, and no extra calcium or vitamin D supplement without asking.¹

Can I take vitamin D with B12, folic acid, iron or magnesium?

Yes. None is on the vitamin D lists and vitamin D is on none of theirs. Iron's own spacing rules are with zinc, calcium and levothyroxine (what you should not take with zinc).^{1, 11, 16}

Are there 8 medications you should avoid with vitamin D?

The NHS has seven groups, and none is "avoid": each is "tell your doctor".^{1, 3, 4}

Sources

1. NHS. Taking colecalciferol with other medicines and herbal supplements (last reviewed 10 January 2023; fetched 10 October 2026, 21:18 UTC). nhs.uk.
2. NHS. Vitamin D. nhs.uk.
3. NICE. BNF: colecalciferol, interactions. bnf.nice.org.uk.
4. NICE CKS. Vitamin D deficiency in adults: vitamin D supplements. cks.nice.org.uk.
5. NICE. BNF: ergocalciferol, interactions. bnf.nice.org.uk.
6. NHS. Common questions about colecalciferol. nhs.uk.
7. NHS. Diltiazem: taking it with other medicines. nhs.uk.
8. NHS. Verapamil: taking it with other medicines. nhs.uk.
9. SmPC, one UK modified-release diltiazem capsule, section 4.5. medicines.org.uk.
10. NHS. Atorvastatin. nhs.uk.
11. NHS. Levothyroxine. nhs.uk.
12. NHS. Carbimazole: taking it with other medicines. nhs.uk.
13. McDuffie JR, et al. Effects of orlistat on fat-soluble vitamins in obese adolescents. Pharmacotherapy, 2002. PubMed 12126214.
14. NHS. How and when to take colecalciferol. nhs.uk.
15. Dawson-Hughes B, et al. Dietary fat increases vitamin D-3 absorption. J Acad Nutr Diet, 2015. PubMed 25441954.
16. Dai Q, et al. Magnesium status and supplementation influence vitamin D status and metabolism. Am J Clin Nutr, 2018. PubMed 30541089.
17. Yao P, et al. Vitamin D and calcium for the prevention of fracture. JAMA Netw Open, 2019. PubMed 31860103.
18. NHS. Calcium. nhs.uk.
19. Diederichsen ACP, et al. Vitamin K2 and D in patients with aortic valve calcification. Circulation, 2022. PubMed 35465686.
20. NHS. Vitamin K. nhs.uk.
21. NHS. Vitamins for children. nhs.uk.
22. NHS. Who can and cannot take colecalciferol. nhs.uk.

General information, not medical advice: ask your pharmacist about any supplement you take alongside a prescribed medicine.