Major interaction on record — check this product against your medications before combining. Based on 4 of 5 ingredients. Check your meds →
Dietary supplement

Methylated Multi-Vitamin Ingredients & Drug Interactions

by Double Wood Supplements

Methylated Multi-Vitamin label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Methylated Multi-Vitamin against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Major

Methylated Multi-Vitamin is a dietary supplement by Double Wood Supplements with 5 active ingredients. Its ingredients are commonly taken for treating or preventing b12 deficiency, pernicious anemia, low energy and fatigue.Based on those ingredients, 323 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Vitamin B6, Calcium L-5-Methyltetrahydrofolate, Vitamin B12. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Methylated Multi-Vitamin by Double Wood Supplements

Ask about any prescription or over-the-counter medication and we check it for interactions with Methylated Multi-Vitamin by Double Wood Supplements — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Methylated Multi-Vitamin by Double Wood Supplements

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 6 of its 6 active ingredients.
  • “Vitamin B12” is listed as a grouped ingredient — the label gives one combined amount (1,000 mcg) without saying how much of each component you get.
  • “Folate” is listed as a grouped ingredient — the label gives one combined amount (1,666 mcg DFE) without saying how much of each component you get.

This six-ingredient multivitamin centers on B-complex vitamins and folate. You're getting riboflavin, vitamin B6, two forms of B12 (methylcobalamin and dibencozide), and calcium L-5-methyltetrahydrofolate (a form of folate).

You'll also find trimethylglycine. The product contains inactive ingredients—rice flour, cellulose, and magnesium stearate—to hold the capsule together.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Sideroblastic anemia — rated "Effective" (Vitamin B6) (Natural Medicines).
  • On file: Dyspepsia — rated "Effective" (Calcium) (Natural Medicines).
  • On file: Hypocalcemia — rated "Effective" (Calcium) (Natural Medicines).
  • On file: Imerslund-Grasbeck disease — rated "Effective" (Vitamin B12) (Natural Medicines).
  • On file: Kidney failure — rated "Effective" (Calcium) (Natural Medicines).

The evidence varies by ingredient. Vitamin B6 is effective for sideroblastic anemia and B6 deficiency, and it's likely effective for high homocysteine levels; it's possibly effective for pregnancy-related nausea.

The B12 forms (methylcobalamin and dibencozide) are effective for B12 deficiency and a rare genetic condition called Imerslund-Grasbeck disease, likely effective for cyanide poisoning, and possibly effective for canker sores and nerve pain after shingles. Calcium is effective for low blood calcium and high potassium levels, and likely effective for osteoporosis.

We don't have effectiveness data on file for riboflavin, folate, or trimethylglycine in this product.

The evidence, ingredient by ingredient Vitamin B12 Riboflavin Calcium Vitamin B6

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 4 of the 4 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 4 of 4.
  • General safety write-ups exist for 4 of 4.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Riboflavin is very well tolerated; excess washes out in your urine. You might notice nausea or bright yellow urine at higher doses.

Vitamin B6 is safe at normal amounts, but high doses over time can damage nerves (sensory neuropathy). It's often used for morning sickness under a doctor's care, but stick to recommended levels unless a clinician advises otherwise.

Both B12 forms are very safe with no upper limit set, and excess is removed in urine; rare allergic reactions (rash, itching) are possible. Calcium is well tolerated at recommended doses but can cause belching, constipation, or stomach upset.

There's theoretical concern about very high calcium intake and prostate cancer or heart disease, though evidence is mixed. Riboflavin and both B12 forms are considered safe in pregnancy and breastfeeding at normal amounts.

Vitamin B6 has no pregnancy or breastfeeding data on file—talk with your provider about its use during these times. Calcium is likely safe in pregnancy and breastfeeding at recommended amounts, though one entry flags it as possibly unsafe in lactation; discuss dosing with your doctor.

Side effects, ingredient by ingredient Vitamin B12 Riboflavin Calcium Vitamin B6

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 4 of the 4 matched ingredients can interact with medications — Calcium, Vitamin B12, Vitamin B6, Riboflavin.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: heart-rhythm medications; lithium; Parkinson's medications.
  • For scale: 323 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before you take this, double-check HIV integrase inhibitors (dolutegravir, elvitegravir, raltegravir)—calcium can significantly lower their blood levels. Also screen for seizure medications (phenobarbital, phenytoin), blood pressure drugs, thyroid hormone (levothyroxine), heart medications (amiodarone, diltiazem, sotalol), the psoriasis drug calcipotriene, tetracycline antibiotics, and metformin for diabetes.

The calcium-antibiotic interaction with intravenous ceftriaxone is especially serious.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with strong clinical evidence behind its ingredients' uses. Major medication interactions have been identified, and safety information is well characterized.

This is a solid B-complex and folate multi for general support. If you take any prescription—especially blood pressure drugs, seizure medications, diabetes drugs, thyroid hormone, a heart rhythm drug, or any HIV medication—check with your pharmacist first.

The calcium here can interfere with several important medications, and B6 at high doses poses risks with seizure and heart drugs. Pregnant or nursing?

Touch base with your provider about the B6 dosing.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 5 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Mar 25, 2025.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Methylated Multi-Vitamin, straight from the product label.

Brand Double Wood Supplements
Barcode (UPC) 810142230193
Net contents 120 Capsule(s)
Market status On market
Date entered into DSLD Mar 25, 2025
DSLD ID 331350
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating), Gluten Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Methylated Multi-Vitamin by Double Wood Supplements, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
120
UPC/BARCODE
810142230193
IngredientAmount% DV
Vitamin B121000 mcg41667%
Riboflavin12.5 mg962%
Folate1666 mcg DFE417%
Vitamin B612.5 mg735%
Methylcobalamin900 mcg--
Trimethylglycine100 mg--
Dibencozide100 mcg--
Calcium L-5-Methyltetrahydrofolate1000 mcg--

Other ingredients: Rice Flour, Cellulose, Magnesium Stearate

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Formula

Double Wood's Methylated Multivitamin contains active/methylated vitamins only. It contains R5P, P5P, methylfolate, methylcobalamin, dibencozide, and trimethylglycine.

Contains activated / methylated vitamins only

Suggested/Recommended/Usage/Directions

Suggested use: As a dietary supplement take 1 serving per day with or without food.

Can be combined with a normal muti-vitamin

Seals/Symbols

Good Manufacturing Practice Certified GMP Quality Made with Non-GMO Ingredients

Formulation

Made with Non-GMO Ingredients Gluten free

Storage

Storage: Store in a cool, dark place. Do not freeze or expose to moisture or heat above room temperature after opening.

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

FDA Statement of Identity

Dietary Supplement

Precautions

Warning: Consult your physician before use. Discontinue use and consult your doctor immediately if any adverse reactions occur. Do not use this supplement and operate heavy machinery until you know how it affects you. Do not exceed 2 capsules per day.

Do not use a Methylated Multivitamin if you are pregnant, nursing, or are under 18 years of age.

Do not use a Methylated Multivitamin if you are pregnant, nursing, or are under 18 years of age. Keep out of reach of children.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Methylated Multi-Vitamin by Double Wood Supplements label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Methylated Multi-Vitamin label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Methylated Multi-Vitamin by Double Wood Supplements

These are the 5 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container120 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Vitamin B12

Interacts with
20 drugs
1000 mcg per serving

Vitamin B12 (cobalamin) is an essential nutrient your body needs to make red blood cells, keep nerves healthy, and support DNA. Supplements are very h...

Vitamin B12 monograph & interactions

Riboflavin

Interacts with
20 drugs
12.5 mg per serving Form: Riboflavin 5-Phosphate, Vitamin B2

Riboflavin (vitamin B2) is an essential nutrient your body needs to turn food into energy and to keep skin, eyes, and nerves healthy. It is generally...

Riboflavin monograph & interactions

Folate

1666 mcg DFE per serving

Vitamin B6

Interacts with
210 drugs
12.5 mg per serving Form: Pyridoxal 5-Phosphate

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is b...

Vitamin B6 monograph & interactions

Trimethylglycine

100 mg per serving Form: Betaine Anhydrous

Other (inactive) ingredients: Rice Flour, Cellulose, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Methylated Multi-Vitamin by Double Wood Supplements Drug Interactions

Want to check YOUR meds against Methylated Multi-Vitamin?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
323Drugs
7 Major 289 Moderate 27 Minor

Ingredients driving the most interactions

Vitamin B6 210
Calcium L-5-Methyltetrahydrofolate 168
Vitamin B12 20
Riboflavin 20

Individual Drug Interactions

The ingredients in Methylated Multi-Vitamin interact with 323 drugs. Click any drug to see the details.

4 of the 5 ingredients in Methylated Multi-Vitamin interact with drugs. Each result below shows which ingredient is responsible. Vitamin B6 Calcium L-5-Methyltetrahydrofolate Vitamin B12 Riboflavin

Each ingredient & the kinds of drugs it affects

For each ingredient in Methylated Multi-Vitamin with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Vitamin B65 drug types · 210 drugs

Amiodarone (Cordarone)

Theoretically, vitamin B6 might increase the photosensitivity caused by amiodarone.
Despite initial case reports suggesting that pyridoxine may have a protective effect against amiodarone-induced photosensitivity, preliminary clinical research suggests that pyridoxine may actually exacerbate this adverse effect.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, vitamin B6 may have additive effects when used with antihypertensive drugs.
Research in hypertensive rats shows that vitamin B6 can decrease systolic blood pressure. Similarly, clinical research in patients with hypertension shows that taking high doses of vitamin B6 may reduce systolic and diastolic blood pressure, possibly by reducing plasma levels of epinephrine and norepinephrine.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

High doses of vitamin B6 may reduce the levels and clinical effects of phenobarbital.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenobarbital, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenobarbital to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Phenytoin (Dilantin)

High doses of vitamin B6 may reduce the levels and clinical effects of phenytoin.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenytoin, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenytoin to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Levodopa

Vitamin B6 may increase the metabolism of levodopa when taken alone, but not when taken in conjunction with carbidopa.
Vitamin B6 (pyridoxine) enhances the metabolism of levodopa, reducing its clinical effects. However, this interaction does not occur when carbidopa is used concurrently with levodopa (Sinemet). Therefore, it is not likely to be a problem in most people.

Likelihood Unlikely Evidence D
Vitamin B6 full monograph & interactions

Calcium L-5-Methyltetrahydrofolate18 drug types · 168 drugs

Ceftriaxone (Rocephin)

Co-administration of intravenous calcium and ceftriaxone can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys.
Avoid administering intravenous calcium in any form, such as parenteral nutrition or Lactated Ringers, within 48 hours of intravenous ceftriaxone. Case reports in neonates show that administering intravenous ceftriaxone and calcium can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys. In several cases, neonates have died as a result of this interaction. So far there are no reports in adults; however, there is still concern that this interaction might occur in adults.

Likelihood Probable Evidence D
Dolutegravir (Tivicay)

Calcium seems to reduce levels of dolutegravir.
Advise patients to take dolutegravir either 2 hours before or 6 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium carbonate 1200 mg concomitantly with dolutegravir 50 mg reduces plasma levels of dolutegravir by almost 40%. Calcium appears to decrease levels of dolutegravir through chelation.

Likelihood Probable Evidence B
Elvitegravir (Vitekta)

Calcium seems to reduce levels of elvitegravir.
Advise patients to take elvitegravir either 2 hours before or 2 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium along with elvitegravir can reduce blood levels of elvitegravir through chelation.

Likelihood Probable Evidence B
Aluminum

Calcium citrate might increase aluminum absorption and toxicity. Other types of calcium do not increase aluminum absorption.
Calcium citrate can increase the absorption of aluminum when taken with aluminum hydroxide. The increase in aluminum levels may become toxic, particularly in individuals with kidney disease. However, the effect of calcium citrate on aluminum absorption is due to the citrate anion rather than calcium cation. Calcium acetate does not appear to increase aluminum absorption.

Likelihood Possible Evidence B
Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Calcium might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide and calcium can be taken together if taken with food. However, if taken on an empty stomach, bictegravir/emtricitabine/tenofovir alafenamide should not be taken with, or 2 hours after, calcium containing products.

Likelihood Probable Evidence D
Bisphosphonates

Calcium reduces the absorption of bisphosphonates.
Advise patients to take bisphosphonates at least 30 minutes before calcium, but preferably at a different time of day. Calcium supplements decrease absorption of bisphosphonates.

Likelihood Probable Evidence C
Calcipotriene (Dovonex)

Taking calcipotriene with calcium might increase the risk for hypercalcemia.
Calcipotriene is a vitamin D analog used topically for psoriasis. It can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia. Theoretically, combining calcipotriene with calcium supplements might increase the risk of hypercalcemia.

Likelihood Possible Evidence B
Digoxin (Lanoxin)

Using intravenous calcium with digoxin might increase the risk of fatal cardiac arrhythmias.
Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. However, one retrospective analysis of clinical data suggests that intravenous calcium does not increase the risk of dysrhythmias or mortality in patients receiving digoxin.

Likelihood Possible Evidence B
Diltiazem (Cardizem, Others)

Theoretically, calcium may reduce the therapeutic effects of diltiazem.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, calcium might increase this risk of hypercalcemia and reduce the effectiveness of diltiazem.

Likelihood Probable Evidence D
Levothyroxine (Synthroid, Others)

Calcium seems to reduce the absorption and effectiveness of levothyroxine.
Advise patients to take levothyroxine and calcium supplements at least 4 hours apart. Calcium reduces levothyroxine absorption, probably by forming insoluble complexes. Calcium carbonate supplements reduce effectiveness of levothyroxine in patients with hypothyroidism.

Likelihood Probable Evidence B
Lithium

Theoretically, concomitant use of calcium and lithium may increase this risk of hypercalcemia.
Clinical research suggests that long-term use of lithium may cause hypercalcemia in 10% to 60% of patients. Theoretically, concomitant use of lithium and calcium supplements may further increase this risk.

Likelihood Possible Evidence B
Quinolone Antibiotics

Calcium seems to reduce the absorption of quinolone antibiotics.
Advise patients to take oral quinolones at least 2 hours before or 4-6 hours after calcium supplements or calcium-fortified foods. Taking calcium at the same time as oral quinolones can reduce quinolone absorption. Calcium binds to quinolones in the gut.

Likelihood Probable Evidence B
Raltegravir (Isentress)

Calcium may reduce levels of raltegravir.
Pharmacokinetic research shows that taking a single dose of calcium carbonate 3000 mg along with raltegravir 400 mg twice daily modestly decreases the mean area under the curve of raltegravir, but the decrease does not necessitate a dose adjustment of raltegravir. However, a case of elevated HIV-1 RNA levels and documented resistance to raltegravir has been reported for a patient taking calcium carbonate 1 gram three times daily plus vitamin D3 (cholecalciferol) 400 IU three times daily in combination with raltegravir 400 mg twice daily for 11 months. It is thought that calcium reduced raltegravir levels by chelation, leading to treatment failure.

Likelihood Possible Evidence B
Sotalol (Betapace)

Calcium seems to reduce the absorption of sotalol.
Advise patients to separate doses by at least 2 hours before or 4-6 hours after calcium. Calcium appears to reduce the absorption of sotalol, probably by forming insoluble complexes.

Likelihood Possible Evidence B
Tetracycline Antibiotics

Calcium seems to reduce the absorption of tetracycline antibiotics.
Advise patients to take oral tetracyclines at least 2 hours before, or 4-6 hours after calcium supplements. Taking calcium at the same time as oral tetracyclines can reduce tetracycline absorption. Calcium binds to tetracyclines in the gut.

Likelihood Probable Evidence C
Thiazide Diuretics

Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Thiazides reduce calcium excretion by the kidneys. Using thiazides along with moderately large amounts of calcium carbonate increases the risk of milk-alkali syndrome (hypercalcemia, metabolic alkalosis, renal failure). Patients may need to have their serum calcium levels and/or parathyroid function monitored regularly.

Likelihood Probable Evidence C
Verapamil (Calan, Others)

Theoretically, calcium may reduce the therapeutic effects of verapamil.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, use of calcium supplements may increase this risk of hypercalcemia and reduce the effectiveness of verapamil.

Likelihood Probable Evidence D
Calcium Channel Blockers

Intravenous calcium may decrease the effects of calcium channel blockers; oral calcium is unlikely to have this effect.
Intravenous calcium is used to decrease the effects of calcium channel blockers in the management of overdose. Intravenous calcium gluconate has been used before intravenous verapamil (Isoptin) to prevent or reduce the hypotensive effects without affecting the antiarrhythmic effects. But there is no evidence that dietary or supplemental calcium when taken orally interacts with calcium channel blockers.

Likelihood Unlikely Evidence D
Calcium L-5-Methyltetrahydrofolate full monograph & interactions

Vitamin B121 drug type · 20 drugs

Metformin (Glucophage)

Metformin, a common medication used to manage type 2 diabetes, has been associated with lower vitamin B12 levels in some individuals. Prolonged use of metformin can interfere with the absorption of B12 in the digestive system, potentially leading to a deficiency in this essential vitamin.

Likelihood Possible Evidence A
Vitamin B12 full monograph & interactions

Riboflavin1 drug type · 20 drugs

Tetracycline Antibiotics

Theoretically, taking riboflavin with tetracycline antibiotics may decrease the potency of these antibiotics.
In vitro research suggests that riboflavin may inhibit the potency of tetracycline antibiotics. It is not clear if this effect is clinically significant, as this interaction has not been reported in humans.

Likelihood Possible Evidence D
Riboflavin full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Methylated Multi-Vitamin, from the product label.

Double Wood Supplements

See all Double Wood Supplements products
Name
Double Wood LLC
Street Address
205 Elmwood Ave
City
Sharon Hill
State
PA
ZipCode
19079
Web Address
www.doublewoodsupplements.com
Pharmacist Counseling Corner

Methylated Multi-Vitamin by Double Wood Supplements: Common Questions

Does Methylated Multi-Vitamin by Double Wood Supplements interact with any medications?
Yes. Based on its ingredients, Methylated Multi-Vitamin has a known interaction with 323 medications, including 7 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Methylated Multi-Vitamin contains 5 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is this safe to take if I'm pregnant or breastfeeding?
Riboflavin and both B12 forms are safe in pregnancy and breastfeeding at recommended amounts. Calcium is likely safe in pregnancy at normal doses, but one data entry flags it as possibly unsafe during breastfeeding—ask your provider about the right amount for you. Vitamin B6 doesn't have pregnancy or breastfeeding data on file here, so check with your doctor before taking it at higher doses during these times.
Why is my urine bright yellow after taking this?
That's the riboflavin. At higher doses, it can turn your urine bright yellow—it's harmless, and the excess vitamin just washes out in your urine.
What does the methylated part mean?
The product uses methylated forms of B vitamins—mainly methylcobalamin and calcium L-5-methyltetrahydrofolate—which are versions your body can use directly without needing to convert them first. Some people find they absorb or tolerate these forms better.
Can I take this with my levothyroxine (Synthroid)?
The calcium in this multi can reduce how much levothyroxine your body absorbs. Take your levothyroxine at least 4 hours apart from this multivitamin to be safe—talk to your pharmacist about the best timing.
Does this help with energy or fatigue?
B vitamins like B6 and B12 are essential for how your body makes energy, and this product includes active forms of them. However, the evidence we have on file doesn't specifically show this multi prevents or reverses fatigue in healthy people. If you have a B12 or B6 deficiency, correcting it can help, but start with your doctor.
Are there any fillers in here?
Yes—the inactive ingredients are rice flour, cellulose, and magnesium stearate. These are used to bind and fill the capsule so it holds together.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Methylated Multi-Vitamin label
Go deeper

The Full Monographs Behind Methylated Multi-Vitamin’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Vitamin B12

Interacts with 20 drugs

Vitamin B12 (cobalamin) is an essential nutrient your body needs to make red blood cells, keep nerves healthy, and support DNA. Supplements are very helpful for people who are deficient — su...

Read the full Vitamin B12 monograph → Herb & supplement monograph

Riboflavin

Interacts with 20 drugs

Riboflavin (vitamin B2) is an essential nutrient your body needs to turn food into energy and to keep skin, eyes, and nerves healthy. It is generally very safe at typical doses, and the stro...

Read the full Riboflavin monograph → Herb & supplement monograph

Calcium

Interacts with 168 drugs

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet falls short. Most people do best getting...

Read the full Calcium monograph → Herb & supplement monograph

Vitamin B6

Interacts with 210 drugs

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is best known for helping with pregnancy-rel...

Read the full Vitamin B6 monograph →
Sources

Sources & How We Checked

Methylated Multi-Vitamin's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 129 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Vitamin B12 30 references
  1. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (2000). Washington, DC: National Academy Press, 2000. Available at: http://b
  2. Hartman TJ, Woodson K, Stolzenberg-Solomon R, et al. Association of the B-vitamins pyridoxal 5'-phosphate (B6), B12, and folate with lung cancer risk in older men. Am J Epidemiol 2001;153:688-94.. DOI
  3. Jansen T, Romiti R, Kreuter A, Altmeyer P. Rosacea fulminans triggered by high-dose vitamins B6 and B12. J Eur Acad Dermatol Venereol 2001;15:484-5..
  4. Lange H, Suryapranata H, De Luca G, et al. Folate therapy and in-stent restenosis after coronary stenting. N Engl J Med 2004;350:2673-81. PubMed
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See these in context on the Vitamin B12 monograph →

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See these in context on the Riboflavin monograph →

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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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