Major interaction on record — check this product against your medications before combining. Based on 5 of 6 ingredients. Check your meds →
Dietary supplement

Methyl Shield Ingredients & Drug Interactions

by NHC Natural Healthy Concepts

Methyl Shield 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 Methyl Shield 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

Methyl Shield is a dietary supplement by NHC Natural Healthy Concepts with 6 active ingredients. Its ingredients are commonly taken for riboflavin deficiency, migraine prevention, general energy and metabolism support.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 Folinate, Riboflavin. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Methyl Shield by NHC Natural Healthy Concepts

Ask about any prescription or over-the-counter medication and we check it for interactions with Methyl Shield by NHC Natural Healthy Concepts — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Methyl Shield by NHC Natural Healthy Concepts

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 Aug 20, 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.
  • “Folate” is listed as a grouped ingredient — the label gives one combined amount (2,000 mcg DFE) without saying how much of each component you get.

Methyl Shield contains 6 active ingredients: riboflavin (vitamin B2), folate, vitamin B12, vitamin B6, calcium folinate, and betaine anhydrous. These are B vitamins and related compounds that support cellular energy production, nerve function, and the breakdown of homocysteine—a protein byproduct linked to cardiovascular and bone health.

The product also contains inactive ingredients including capsule material (HPMC), thickeners, and flow agents.

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
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: support optimal methylation and healthy homocysteine.
  • We looked for evidence on: Homocystinuria, Hyperhomocysteinemia, Cardiovascular disease (CVD), Atherosclerosis, Cognitive function, Cognitive impairment — and 4 related terms.
  • The strongest evidence on file: Betaine Anhydrous is rated "Effective" for Homocystinuria (Natural Medicines).
  • Also on file: Vitamin B6 is rated "Likely Effective" for Hyperhomocysteinemia.
  • Also on file: Vitamin B12 is rated "Possibly Effective" for Hyperhomocysteinemia.

Vitamin B12 in this product is effective for treating B12 deficiency, Imerslund-Grasbeck disease (a rare absorption disorder), and cyanide poisoning, and possibly effective for canker sores and nerve pain after shingles. Vitamin B6 is effective for sideroblastic anemia (an inherited blood disorder) and B6 deficiency itself, and likely effective for elevated homocysteine.

Betaine anhydrous is effective for homocystinuria (a rare metabolic disorder) and possibly effective for elevated homocysteine, but evidence is insufficient for its use in fatty liver disease, colon polyps, depression, or acid reflux. We don't hold effectiveness data for riboflavin or calcium folinate's primary uses in this product.

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

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 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Riboflavin is very well tolerated; any excess leaves in your urine. The main side effects are dose-related nausea and bright yellow urine at high doses—rare.

It's needed during pregnancy and breastfeeding at normal amounts; check with your provider before high-dose supplements. Vitamin B12 is very safe with no upper limit and is generally well tolerated; it's needed in pregnancy and during breastfeeding.

Rare allergic reactions (rash, itching) are possible, and very rarely, correcting severe anemia with B12 can cause a dangerous drop in potassium. Vitamin B6 is well tolerated below 100 mg daily, but high doses over time can damage nerves (sensory neuropathy).

Use only recommended amounts unless a doctor advises otherwise, especially in pregnancy—safety data is mixed at higher doses. Betaine anhydrous is generally well tolerated at studied doses but may cause body odor, nausea, stomach upset, diarrhea, or elevated cholesterol; safety in pregnancy is not well established, and data during breastfeeding are limited.

Calcium folinate is generally safe at recommended amounts but high doses can cause problems; rare serious side effects include kidney stones.

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

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 5 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 taking Methyl Shield, check with your doctor or pharmacist if you take HIV integrase inhibitors (dolutegravir, elvitegravir, raltegravir)—calcium in this product can significantly reduce their blood levels. Also double-check if you use blood pressure medications, seizure drugs (phenobarbital, phenytoin), heart medications (amiodarone, diltiazem, sotalol), thyroid replacement (levothyroxine), levodopa for Parkinson's disease, metformin for diabetes, tetracycline antibiotics, the antibiotic ceftriaxone, or calcipotriene for psoriasis.

No interactions are documented in our data for the ingredient quatrefolic.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

Methyl Shield is a B-vitamin and methylation-support formula that may help if you have B12 deficiency, elevated homocysteine, or certain rare metabolic disorders. If you take any prescription medication—especially HIV drugs, seizure medications, blood pressure drugs, thyroid replacement, heart drugs, or antibiotics—check your exact medications with the tool on this page before starting.

Talk with your own doctor or pharmacist about whether this product is right for your health and medications.

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 Jul 23, 2020.

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 Methyl Shield, straight from the product label.

Brand NHC Natural Healthy Concepts
Barcode (UPC) 647732924749
Net contents 120 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Jul 23, 2020
DSLD ID 230789
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy 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 Methyl Shield by NHC Natural Healthy Concepts, 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
647732924749
IngredientAmount% DV
Riboflavin25 mg1923%
Folate2000 mcg DFE500%
Vitamin B121000 mcg41667%
Vitamin B610 mg588%
Calcium Folinate1000 mcg DFE--
Betaine Anhydrous500 mg--
Quatrefolic1000 mcg DFE--

Other ingredients: HPMC, Stearic Acid, Silica, Microcrystalline Cellulose, Magnesium Stearate, Medium-Chain Triglyceride Oil

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.
General Statements

Professional use only

This package is completely recyclable

Suggested/Recommended/Usage/Directions

Directions: Take one capsule one to two times daily, or as directed by your healthcare practitioner.

Precautions

Consult your healthcare practitioner prior to use.

Individuals taking medication should discuss potential interactions with their healthcare practitioner.

Do not use if tamper seal is damaged.

Storage: Keep closed in a cool, dry place out of reach of children.

Formulation

Methyl Shield is a comprehensive formula designed to support optimal methylation and help maintain healthy homocysteine levels already within normal range.

Does not contain: Wheat, gluten, corn, yeast, soy, animal or dairy products, fish, shellfish, peanuts, tree nuts, egg, ingredients derived from genetically modified organisms (GMOs), artificial colors, artificial sweeteners, or artificial preservatives.

Optimal Methylation support formula

Gluten free Dairy free Soy free Nut free

Manufactured in a GMP compliant facility.

Formula

It features five key nutrients that are involved in homocysteine metabolism: folate as calcium folinate and Quatrefolic for increased bioactivity; trimethylglycine; and vitamins B12, B6, and B2. These five nutrients, provided in activated forms, support enhanced methylation and overall cardiovascular health.

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.

Storage

Storage: Keep closed in a cool, dry place out of reach of children.

FDA Statement of Identity

Dietary Supplement

Brand IP Statement(s)

Quatrefolic is a registered trademark of Gnosis S.p.A. Produced under US patent 7,947,662.

Seals/Symbols

Vegetarian Caps

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

See for yourself

Methyl Shield by NHC Natural Healthy Concepts label

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

Methyl Shield 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 Methyl Shield by NHC Natural Healthy Concepts

These are the 6 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.

Riboflavin

Interacts with
20 drugs
25 mg per serving Form: Riboflavin 5'-Phosphate Sodium

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

2000 mcg DFE per serving

Vitamin B12

Interacts with
20 drugs
1000 mcg per serving Form: Methylcobalamin

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

Vitamin B6

Interacts with
210 drugs
10 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

Betaine Anhydrous

No known
interactions
500 mg per serving

Betaine anhydrous (also called trimethylglycine) is a compound found in foods like beets, spinach, and whole grains, and is sold as a supplement and a...

Betaine Anhydrous monograph & interactions

Other (inactive) ingredients: HPMC, Stearic Acid, Silica, Microcrystalline Cellulose, Magnesium Stearate, Medium-Chain Triglyceride Oil. These complete the product’s ingredient list but are not active constituents.

Interaction report

Methyl Shield by NHC Natural Healthy Concepts Drug Interactions

Want to check YOUR meds against Methyl Shield?

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 Folinate 168
Riboflavin 20
Vitamin B12 20

Individual Drug Interactions

The ingredients in Methyl Shield interact with 323 drugs. Click any drug to see the details.

4 of the 6 ingredients in Methyl Shield interact with drugs. Each result below shows which ingredient is responsible. Vitamin B6 Calcium Folinate Riboflavin Vitamin B12

Each ingredient & the kinds of drugs it affects

For each ingredient in Methyl Shield 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 Folinate18 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 Folinate 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

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
The maker

Brand information

Manufacturer and brand details for Methyl Shield, from the product label.

NHC Natural Healthy Concepts

See all NHC Natural Healthy Concepts products
Name
NHC
Street Address
310 N Westhill Blvd.
City
Appleton
State
WI
ZipCode
54914
Pharmacist Counseling Corner

Methyl Shield by NHC Natural Healthy Concepts: Common Questions

Does Methyl Shield by NHC Natural Healthy Concepts interact with any medications?
Yes. Based on its ingredients, Methyl Shield 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?
Methyl Shield contains 6 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.
Can I take Methyl Shield if I'm pregnant?
The B vitamins in this product—riboflavin, B12, and B6—are needed during pregnancy and rated likely safe or possibly safe at recommended amounts. However, vitamin B6 safety data are mixed at higher doses, and betaine anhydrous safety hasn't been well established in pregnancy. Talk with your doctor before starting, especially if you're considering high doses.
Is it safe while breastfeeding?
Riboflavin and vitamin B12 are needed during breastfeeding and are safe at recommended amounts. Vitamin B6 is rated likely safe while breastfeeding. Betaine anhydrous, however, has limited safety data during breastfeeding—ask your provider about it before use.
What side effects might I notice?
Most common are nausea and bright yellow urine from riboflavin (especially at high doses), stomach upset or diarrhea from betaine, and rarely, headache or body odor. At very high doses of vitamin B6, nerve damage (numbness and tingling) is possible with long-term use. If you notice new symptoms, contact your doctor.
Does this product actually work?
Vitamin B12 is proven effective for B12 deficiency and certain rare disorders. Vitamin B6 is proven for B6 deficiency and certain anemias. Betaine is effective for homocystinuria and may help lower homocysteine. Evidence for betaine in fatty liver, depression, or acid reflux is not yet established. We don't have effectiveness data on file for riboflavin or calcium folinate in this context.
What is betaine anhydrous and why is it in here?
Betaine is an amino acid that helps break down homocysteine, a protein in your blood linked to heart and bone health. It's effective for a rare disorder called homocystinuria and possibly helpful for lowering elevated homocysteine levels.
Why do I need to separate this from my levothyroxine?
Calcium in this product can bind to levothyroxine and prevent your body from absorbing it, making the thyroid medication less effective. Take them at least 4 hours apart—your pharmacist can help you figure out a schedule that works.

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.

Methyl Shield label
Go deeper

The Full Monographs Behind Methyl Shield’s Ingredients

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

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 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

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 → Herb & supplement monograph

Betaine Anhydrous

Betaine anhydrous (also called trimethylglycine) is a compound found in foods like beets, spinach, and whole grains, and is sold as a supplement and as a prescription medicine for a rare gen...

Read the full Betaine Anhydrous monograph →
Sources

Sources & How We Checked

Methyl Shield'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 140 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.

Riboflavin 5 references
  1. Schoenen J, Jacquy J, Lenaerts M. Effectiveness of high-dose riboflavin in migraine prophylaxis. A randomized controlled trial. Neurology 1998;50:466-70. PubMed
  2. Yates AA, Schlicker SA, Suitor CW. Dietary reference intakes: The new basis for recommendations for calcium and related nutrients, B vitamins, and choline. J Am Diet Assoc 1998;98:699-706. PubMed
  3. Leeson LJ, Weidenheimer JF. Stability of tetracycline and riboflavin. J Pharm Sci. 1969;58(3):355-7. PubMed
  4. MacLennan, S. C., Wade, F. M., Forrest, K. M., Ratanayake, P. D., Fagan, E., and Antony, J. High-dose riboflavin for migraine prophylaxis in children: a double-blind, randomized, placebo-controlled trial. J Child Neurol. 2008;23(11):1300-1304.
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Vitamin B12 30 references
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Vitamin B6 32 references
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Betaine Anhydrous 11 references
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