Supplement·Interactions·Reviewed June 9, 2026
Vitamin D3 interactions.
Vitamin D3 has 73 documented interactions in the NutriStack database: 1 to avoid or watch closely, 10 that need timing or caution, and 62 that work synergistically. The full list, with what each pairing does, is below.
In short
Vitamin D3 at a glance.
A quick, data-grounded summary. The full table is below.
Vitamin D3 has 73 documented interactions in the NutriStack database: 1 to avoid or watch closely, 10 that need timing or caution, and 62 that work synergistically. The full list, with what each pairing does, is below.
Interactions
Everything that interacts with vitamin d3.
Every supplement and medication in the NutriStack database with a documented interaction with this substance, highest-severity first. Open any pair for the mechanism and sources.
| Substance | Interaction | What happens |
|---|---|---|
| Calcitriol | Contraindicated | Additional vitamin D can increase the risk of vitamin D toxicity and hypercalcemia during calcitriol therapy. |
| Chlorthalidone | Caution | Chlorthalidone can increase serum calcium by lowering urinary calcium excretion, while Vitamin D3 increases intestinal calcium absorption. Usual... details → |
| Digoxin | Caution | High-dose vitamin D3 can cause hypercalcemia, and hypercalcemia can make digoxin-related rhythm problems more likely. This is not a routine-dose... details → |
| Ezetimibe | Caution | Ezetimibe blocks intestinal absorption of cholesterol via the Niemann-Pick C1-Like 1 (NPC1L1) transporter. Because fat-soluble vitamin D shares a... |
| Hydrochlorothiazide | Caution | Hydrochlorothiazide can raise serum calcium by reducing urinary calcium loss, while Vitamin D3 increases intestinal calcium absorption. Standard... details → |
| Losartan/Hydrochlorothiazide | Caution | Vitamin D3 increases intestinal calcium absorption. Combined with hydrochlorothiazide's calcium-sparing effect on the kidney, high-dose vitamin D... |
| Rifampin | Caution | Rifampin can accelerate vitamin D catabolism during prolonged therapy and may contribute to low vitamin D or bone risk. |
| Vitamin A | Caution | High-dose vitamin A (retinol) can antagonize vitamin D activity by competing for the shared RXR nuclear receptor. details → |
| Beta-Sitosterol | Timing Sensitive | High-dose plant sterols can modestly reduce absorption of some fat-soluble dietary compounds; clinically important vitamin D effects are not well... |
| Cholestyramine | Timing Sensitive | Cholestyramine can reduce absorption of fat-soluble vitamins including vitamin D. |
| Fucoxanthin | Timing Sensitive | Vitamin D3 is fat-soluble and, like fucoxanthin, depends on dietary fat for absorption. Taking them together with a fat-containing meal supports... |
| Alendronate | Synergy | Adequate vitamin D status is essential for alendronate to work properly. In a multi-year cohort, women whose 25(OH)D rose the most during and after... details → |
| Amlodipine | Synergy | In patients with documented vitamin D deficiency and hypertension, vitamin D supplementation produces a small additional reduction in systolic and... details → |
| Black Cohosh | Synergy | Pairing black cohosh for menopausal vasomotor symptoms with vitamin D3 addresses a complementary need, since postmenopausal women face elevated bone... |
| Boron | Synergy | Boron supports vitamin D metabolism and may increase the half-life of 25(OH)D in the body. |
| Calcium | Synergy | Vitamin D3 is essential for calcium absorption from the gut. Without adequate D3, only 10-15% of dietary calcium is absorbed. details → |
| Calcium Alpha-Ketoglutarate | Synergy | Vitamin D3 increases intestinal calcium absorption, complementing the calcium and bone-supportive aims of Ca-AKG. Adequate vitamin D status helps... |
| Carbamazepine | Synergy | Carbamazepine induces CYP enzymes that accelerate vitamin D metabolism, leading to deficiency, reduced calcium absorption, and increased... details → |
| Cinacalcet | Synergy | Vitamin D therapy can help maintain calcium balance but can also change calcium and phosphate response during cinacalcet treatment. |
| Creatine | Synergy | Both support musculoskeletal function. Vitamin D3 enhances muscle protein synthesis, and creatine increases phosphocreatine stores for energy. |
| Dexamethasone | Synergy | Dexamethasone rapidly depletes vitamin D stores through CYP24A1 induction. Supplementation is essential. |
| Ecdysterone | Synergy | Adequate vitamin D supports muscle function when deficient, but direct ecdysterone synergy is unproven. |
| Elderberry Zinc Lozenges | Synergy | The zinc component can help meet zinc intake, but elderberry zinc lozenges are not required for vitamin D receptor function and should not be framed... |
| Evening Primrose Oil | Synergy | Evening Primrose Oil provides a fat-containing carrier that can improve absorption of fat-soluble compounds like Vitamin D3. |
| Fish Oil | Synergy | Vitamin D3 is fat-soluble and absorption improves when taken with omega-3 fatty acids. Both support cardiovascular and immune health. details → |
| Fish Oil Triple Strength | Synergy | Vitamin D3 is fat-soluble and absorption improves when taken with omega-3 fatty acids. Both support cardiovascular and immune health. details → |
| Flaxseed Oil | Synergy | Flaxseed Oil provides a fat-containing carrier that can improve absorption of fat-soluble compounds like Vitamin D3. |
| HMB | Synergy | Vitamin D supports muscle function and the response to HMB, with combined supplementation showing greater gains in muscle strength and quality,... |
| Ibandronate | Synergy | Adequate vitamin D supports safe and effective antiresorptive therapy by reducing hypocalcemia risk and supporting bone mineralization. |
| Inositol | Synergy | Adequate vitamin D status appears to improve the metabolic and reproductive response to myo-inositol in PCOS, and the two are frequently combined to... |
| Insulin Glargine | Synergy | Vitamin D repletion may gradually improve insulin sensitivity when vitamin D status is low. Because insulin glargine provides basal insulin exposure... details → |
| Krill Oil | Synergy | Same synergy as fish oil + D3. Krill oil phospholipid-bound omega-3s provide dietary fat for D3 absorption. details → |
| Lactobacillus Rhamnosus | Synergy | Vitamin D supports the gut immune barrier. Lactobacillus Rhamnosus modulate the microbiome. Together they support gut-immune axis health. |
| Lamotrigine | Synergy | Unlike enzyme-inducing anticonvulsants (carbamazepine, phenytoin), lamotrigine has minimal effects on CYP-mediated vitamin D catabolism and does not... details → |
| Levetiracetam | Synergy | Levetiracetam has minimal enzyme-inducing effects compared to other anticonvulsants, but long-term use may still modestly reduce vitamin D levels.... |
| Lisinopril | Synergy | Vitamin D directly suppresses renin biosynthesis, so vitamin D deficiency leaves the renin-angiotensin system over-activated. Correcting deficiency... details → |
| LL-37 | Synergy | Vitamin D status influences endogenous cathelicidin expression, but this does not validate exogenous LL-37 use. |
| Losartan | Synergy | Vitamin D directly suppresses renin biosynthesis, so vitamin D deficiency leaves the renin-angiotensin system over-activated. Correcting deficiency... details → |
| Magnesium Citrate | Synergy | Magnesium is essential for vitamin D metabolism. It's required for the enzymes that convert D3 to its active form calcitriol. details → |
| Magnesium Glycinate | Synergy | Magnesium is essential for vitamin D metabolism. It's required for the enzymes that convert D3 to its active form calcitriol. details → |
| Magnesium L-Threonate | Synergy | Magnesium is essential for vitamin D metabolism. It's required for the enzymes that convert D3 to its active form calcitriol. details → |
| Magnesium Malate | Synergy | Magnesium is essential for vitamin D metabolism. It's required for the enzymes that convert D3 to its active form calcitriol. details → |
| Magnesium Taurate | Synergy | Magnesium is essential for vitamin D metabolism. It's required for the enzymes that convert D3 to its active form calcitriol. details → |
| MCT Oil | Synergy | MCT Oil provides a fat-containing carrier that can improve absorption of fat-soluble compounds like Vitamin D3. |
| Medroxyprogesterone | Synergy | Vitamin D adequacy is essential for the bone-protective effect of calcium during DMPA use. Without adequate vitamin D, dietary calcium cannot be... details → |
| Metformin | Synergy | Vitamin D deficiency is common in type 2 diabetes and is associated with insulin resistance. Meta-analyses of vitamin D supplementation in type 2... details → |
| Methylprednisolone | Synergy | Methylprednisolone accelerates vitamin D catabolism. Vitamin D supplementation is standard care for glucocorticoid-induced osteoporosis prevention. |
| Oseltamivir | Synergy | Vitamin D supplementation modestly reduces the risk of acute respiratory infections, particularly in deficient individuals, per a large individual... details → |
| Ox Bile | Synergy | Bile is required to absorb fat-soluble vitamin D3, so ox bile can improve uptake of D3 supplements in people with low bile output, such as those... |
| Phenytoin | Synergy | Phenytoin is a potent CYP enzyme inducer that accelerates vitamin D catabolism through increased 24-hydroxylase activity. Long-term phenytoin use... details → |
| Pioglitazone | Synergy | Pioglitazone increases fracture risk; correcting vitamin D deficiency is relevant to bone-health risk reduction. |
| Prednisolone | Synergy | Chronic prednisolone use increases the risk of osteoporosis and fractures. Vitamin D3 helps maintain calcium absorption and is routinely paired with... details → |
| Prednisone | Synergy | Prednisone impairs vitamin D metabolism and reduces its active form (calcitriol) production. This contributes to decreased calcium absorption and... details → |
| Probiotics | Synergy | Vitamin D supports the gut immune barrier. Probiotics modulate the microbiome. Together they support gut-immune axis health. |
| Raloxifene | Synergy | Vitamin D sufficiency improves calcium absorption and supports raloxifene-based osteoporosis care. |
| Red Clover Isoflavones | Synergy | Vitamin D sufficiency supports calcium absorption and bone health. |
| Risedronate | Synergy | Risedronate, like other bisphosphonates, depends on adequate vitamin D status for full bone benefit and for protection against hypocalcemia. Vitamin... details → |
| Saccharomyces Boulardii | Synergy | Vitamin D supports the gut immune barrier. Saccharomyces Boulardii modulate the microbiome. Together they support gut-immune axis health. |
| Silicon | Synergy | Human and mechanistic data support a complementary, bone-building relationship rather than any adverse interaction. In a 12-month randomized,... |
| Soy Isoflavones | Synergy | Vitamin D sufficiency supports calcium absorption and bone remodeling. |
| Strontium | Synergy | Adequate vitamin D3 supports the calcium handling and bone mineralization environment in which strontium exerts its bone-building and antiresorptive... |
| Tenofovir Disoproxil | Synergy | Tenofovir disoproxil can reduce bone mineral density and may contribute to phosphate wasting; correcting vitamin D deficiency is part of bone-risk... |
| Testosterone | Synergy | Vitamin D deficiency is associated with lower testosterone in observational studies, but a high-quality RCT showed that 20,000 IU/week vitamin D3... details → |
| Thymalin | Synergy | Vitamin D status is relevant to immune function, but it does not validate thymalin use. |
| Thymosin Alpha-1 | Synergy | Vitamin D status is relevant to immune regulation but does not replace immunologic diagnosis. |
| Topiramate | Synergy | Topiramate can reduce vitamin D levels and increase kidney stone risk. Vitamin D supplementation helps prevent bone loss but the carbonic anhydrase... details → |
| Valproic Acid | Synergy | Long-term valproic acid use has been associated with lower 25-hydroxyvitamin D and lower bone mineral density, especially in children and patients... details → |
| Vitamin K2 | Synergy | Vitamin D3 increases calcium absorption, while K2 activates osteocalcin and matrix GLA protein to direct calcium into bones and away from arteries. details → |
| Vitamin K2 MK-4 | Synergy | Vitamin D3 increases calcium absorption, while K2 activates osteocalcin and matrix GLA protein to direct calcium into bones and away from arteries. details → |
| Zinc | Synergy | Adequate zinc status supports normal zinc-finger transcription biology, including vitamin D receptor DNA-binding domains. Evidence does not show... |
| Zinc Carnosine | Synergy | Adequate zinc status supports normal zinc-finger transcription biology, including vitamin D receptor DNA-binding domains. Evidence does not show... |
| Zinc Picolinate | Synergy | Adequate zinc status supports normal zinc-finger transcription biology, including vitamin D receptor DNA-binding domains. Evidence does not show... |
| Zoledronic Acid | Synergy | Vitamin D status strongly predicts both the acute-phase reaction risk (fever, myalgia, flu-like symptoms after infusion) and the risk of... details → |
Go deeper
The full vitamin d3 profile.
Benefits, dosing by goal, forms, and the cited evidence for this supplement.
FAQ
Common vitamin d3 questions.
Quick answers drawn from the table above.
What interacts with Vitamin D3?
In the NutriStack database, Vitamin D3 has 73 documented interactions with other supplements and medications. The most notable include Calcitriol, Chlorthalidone, Digoxin, Ezetimibe, and Hydrochlorothiazide.
What should you not take with Vitamin D3?
Vitamin D3 is flagged against 1 substance in the database, including Calcitriol. Review these with a clinician before combining, especially alongside prescription medications.
What works well with Vitamin D3?
Vitamin D3 pairs synergistically with Alendronate, Amlodipine, Black Cohosh, Boron, and Calcium in the NutriStack database. Synergy still depends on dose and timing; open any pair for the detail.
Can you take Vitamin D3 with Calcitriol?
NutriStack classifies the Vitamin D3 and Calcitriol pairing as contraindicated: Additional vitamin D can increase the risk of vitamin D toxicity and hypercalcemia during calcitriol therapy. Do not add vitamin D supplements unless the prescriber specifically orders them and monitors calcium and vitamin D status.
Check your whole stack
See how vitamin d3 fits your routine.
NutriStack screens your full stack for interactions and timing conflicts, and updates the moment you change it.