Vitamin B-1 100 mg Ingredients & Drug Interactions
by Major
What is this page for?
First and foremost: checking Vitamin B-1 100 mg 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
Vitamin B-1 100 mg is a dietary supplement by Major with 2 active ingredients. Its ingredients are commonly taken for bone health and osteoporosis prevention, dietary calcium deficiency, heartburn relief (calcium carbonate antacids).Based on those ingredients, 168 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Calcium. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Vitamin B-1 100 mg by Major
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AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Vitamin B-1 100 mg by Major
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.
What’s inside
Full disclosure
This product contains 2 active ingredients: calcium and vitamin B1. Calcium is a mineral essential for bone health, muscle function, and kidney regulation; the facts show it's effective for weak bones (osteoporosis), low blood calcium (hypocalcemia), and several other conditions.
Vitamin B1 is a water-soluble vitamin, though the product facts don't specify its roles or effectiveness. The tablet also contains several inactive ingredients — silica, croscarmellose sodium, magnesium stearate, and stearic acid — which help hold the tablet together and aid in swallowing.
Does it work?
Not established
Calcium in this product is backed by evidence for several uses. It's rated Effective for kidney failure, indigestion (dyspepsia), low blood calcium (hypocalcemia), and high potassium (hyperkalemia).
It's Likely Effective for weak bones (osteoporosis). We hold no effectiveness data for the vitamin B1 ingredient in this product.
How safe is it?
Well-documented data
Calcium is generally well tolerated at recommended doses, though high amounts can cause problems. The most common side effects from oral calcium are belching, constipation, diarrhea, bloating, and stomach upset.
Rare serious concerns include kidney stones and a serious skin condition called calciphylaxis. There's also some concern that very high calcium intake — over 1500 to 2000 mg daily — might be linked to increased prostate cancer risk and possibly cardiovascular problems, though research remains mixed and sometimes criticized.
During pregnancy, adequate calcium is important; stick to recommended amounts unless your doctor advises otherwise. During breastfeeding, calcium needs can be met through this supplement, but use recommended amounts and check with your provider.
We hold no safety data for vitamin B1 in pregnancy or breastfeeding.
Meds to double-check
Major interaction found
Before taking this product, double-check with your pharmacist if you use HIV integrase inhibitors (dolutegravir or elvitegravir), the antibiotic ceftriaxone by IV, the thyroid medication levothyroxine, the blood pressure drugs diltiazem or sotalol, the HIV drug raltegravir, or the psoriasis medicine calcipotriene. These are Major or Moderate interactions where timing or monitoring may matter.
We could not check vitamin B1 for medication interactions.
The bottom line
Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Major medication interactions have been identified, and safety information is well characterized.
This product is useful if you need to boost calcium intake for bone health or certain medical conditions, and it's generally well tolerated at normal doses. However, if you take HIV medications, thyroid drugs, heart medications, or the antibiotic ceftriaxone, you'll need to talk with your pharmacist about timing — calcium can interfere with how these work.
Anyone with a personal or family history of kidney stones or prostate cancer should discuss high-dose calcium with their doctor.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 1 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 22, 2022.
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
General information
Key facts about Vitamin B-1 100 mg, straight from the product label.
| Brand | Major |
|---|---|
| Barcode (UPC) | 309040544605 |
| Net contents | 100 Tablet(s) |
| Market status | On market |
| Date entered into DSLD | Sep 22, 2022 |
| DSLD ID | 276918 |
| Product type | Single Vitamin And Mineral |
| Supplement form | Tablet Or Pill |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Dairy Free, Sugar Free |
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 Vitamin B-1 100 mg by Major, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Calcium | 35 mg | 3.5% |
| Vitamin B1 | 100 mg | 6666% |
Other ingredients: Colloidal Silica, Croscarmellose Sodium, Magnesium Stearate, Stearic Acid
Tap any ingredient to jump to its full detail below.
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.
Formulation
Potency guaranteed
Contributes to the health of the nervous system
Free of: Sugar, sodium, starch, wheat, corn, dairy, yeast, soy, egg, fragrance, artificial colors or flavors and preservatives.
Made in the U.S.A.
General Statements
New formula & appearance
FDA Statement of Identity
Dietary Supplement
Suggested/Recommended/Usage/Directions
Directions: One tablet daily as a dietary supplement.
Precautions
Warning: If you are pregnant, nursing, taking any medications or planning any medical procedure, consult your doctor before use.
Discontinue use and consult your doctor if any adverse reactions occur.
Keep out of reach of children.
Tamper Resistant: Do not use if seal under cap is broken or missing.
Formula
As a B vitamin, Thiamine plays a unique role in maintaining proper metabolic function, and is essential for well-being. It promotes energy metabolism, and is also important for carbohydrate and sugar metabolism. In addition, Thiamine promotes nervous system 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
Store at room temperature in a dry place and avoid excessive heat.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Vitamin B-1 100 mg by Major label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Vitamin B-1 100 mg by Major
These are the 2 active ingredients this product is made of. Select any to open its full monograph.
Serving size1 Tablet(s) Dosage formTablet Or Pill Servings per container100 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.
Calcium
Interacts with168 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 f...
Calcium monograph & interactionsVitamin B1
Other (inactive) ingredients: Colloidal Silica, Croscarmellose Sodium, Magnesium Stearate, Stearic Acid. These complete the product’s ingredient list but are not active constituents.
Vitamin B-1 100 mg by Major Drug Interactions
HelloPharmacist Interaction Report
Vitamin B-1 100 mg by Major contains calcium, which does interact with a number of medications.
The most serious concern is with HIV integrase inhibitors — dolutegravir and elvitegravir — where calcium can cut drug levels substantially (by up to 40% in some cases), potentially reducing their effectiveness. You'd need to separate doses by hours: at least 2 hours before or 6 hours after for dolutegravir, and 2 hours before or after for elvitegravir.
Read the full breakdown — every affected drug type, severity by severity
Calcium also poses Major risks with ceftriaxone (an antibiotic given by IV), where it can form dangerous precipitates in the lungs and kidneys — avoid IV calcium within 48 hours of this antibiotic. For moderate interactions, calcium can reduce levels of the HIV drug raltegravir and the thyroid medication levothyroxine, as well as the heart drug diltiazem and the blood pressure medicine sotalol.
It may also raise the risk of high blood calcium (hypercalcemia) if you're using calcipotriene for psoriasis.
We could not check the vitamin B1 ingredient for interactions — we hold no data for it. Altogether, these interactions span 167 individual medications.
Check your exact medications with the search tool on this page before you start.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Vitamin B-1 100 mg?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Vitamin B-1 100 mg interact with 168 drugs. Click any drug to see the details.
1 of the 2 ingredients in Vitamin B-1 100 mg interact with drugs. Each result below shows which ingredient is responsible. Calcium
CeftriaxoneRocephin
How Ceftriaxone interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumCeftriaxone (rocephin) Major
Interaction Summary
Co-administration of intravenous calcium and ceftriaxone can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys.
Read the full Calcium + Ceftriaxone interactionCobicistat, Elvitegravir, Emtricitabine, Tenofovir Alafenamide FumarateGenvoya
How Cobicistat, Elvitegravir, Emtricitabine, Tenofovir Alafenamide Fumarate interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumElvitegravir (vitekta), Bictegravir/emtricitabine/tenofovir Alafenamide (biktarvy) Major
Interaction Summary
Calcium seems to reduce levels of elvitegravir.
Read the full Calcium + Cobicistat, Elvitegravir, Emtricitabine, Tenofovir Alafenamide Fumarate interactionDolutegravirTivicay
How Dolutegravir interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumDolutegravir (tivicay) Major
Interaction Summary
Calcium seems to reduce levels of dolutegravir.
Read the full Calcium + Dolutegravir interactionDolutegravir, Emtricitabine, Tenofovir AlafenamideDolutegravir, Emtricitabine, Tenofovir Alafenamide
How Dolutegravir, Emtricitabine, Tenofovir Alafenamide interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumDolutegravir (tivicay), Bictegravir/emtricitabine/tenofovir Alafenamide (biktarvy) Major
Interaction Summary
Calcium seems to reduce levels of dolutegravir.
Read the full Calcium + Dolutegravir, Emtricitabine, Tenofovir Alafenamide interactionDolutegravir, RilpivirineJuluca
How Dolutegravir, Rilpivirine interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumDolutegravir (tivicay) Major
Interaction Summary
Calcium seems to reduce levels of dolutegravir.
Read the full Calcium + Dolutegravir, Rilpivirine interactionElvitegravirVitekta
How Elvitegravir interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumElvitegravir (vitekta) Major
Interaction Summary
Calcium seems to reduce levels of elvitegravir.
Read the full Calcium + Elvitegravir interactionElvitegravir, Cobicistat, Emtricitabine, Tenofovir Disoproxil FumarateStribild
How Elvitegravir, Cobicistat, Emtricitabine, Tenofovir Disoproxil Fumarate interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumElvitegravir (vitekta), Bictegravir/emtricitabine/tenofovir Alafenamide (biktarvy) Major
Interaction Summary
Calcium seems to reduce levels of elvitegravir.
Read the full Calcium + Elvitegravir, Cobicistat, Emtricitabine, Tenofovir Disoproxil Fumarate interactionAlendronateBinosto, Fosamax
How Alendronate interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumBisphosphonates Moderate
Interaction Summary
Calcium reduces the absorption of bisphosphonates.
Read the full Calcium + Alendronate interactionAlendronate Sodium
How Alendronate Sodium interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumBisphosphonates Moderate
Interaction Summary
Calcium reduces the absorption of bisphosphonates.
Read the full Calcium + Alendronate Sodium interactionAlendronate Sodium, CholecalciferolFosamax Plus D
How Alendronate Sodium, Cholecalciferol interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumBisphosphonates Moderate
Interaction Summary
Calcium reduces the absorption of bisphosphonates.
Read the full Calcium + Alendronate Sodium, Cholecalciferol interactionAlginic Acid, Aluminum HydroxideRafton
How Alginic Acid, Aluminum Hydroxide interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumAluminum Moderate
Interaction Summary
Calcium citrate might increase aluminum absorption and toxicity.
Read the full Calcium + Alginic Acid, Aluminum Hydroxide interactionAluminum Acetate, Benzethonium ChlorideBuro-Sol Otic Solution
How Aluminum Acetate, Benzethonium Chloride interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumAluminum Moderate
Interaction Summary
Calcium citrate might increase aluminum absorption and toxicity.
Read the full Calcium + Aluminum Acetate, Benzethonium Chloride interactionAluminum ChlorideAluminum Chloride, Anhydrol Forte, Driclor, Drysol
How Aluminum Chloride interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumAluminum Moderate
Interaction Summary
Calcium citrate might increase aluminum absorption and toxicity.
Read the full Calcium + Aluminum Chloride interactionAluminum HydroxideAlu-Cap, Amphojel, Gaviscon
How Aluminum Hydroxide interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumAluminum Moderate
Interaction Summary
Calcium citrate might increase aluminum absorption and toxicity.
Read the full Calcium + Aluminum Hydroxide interactionAluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium HydroxideAscriptin Codeine #2
How Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumAluminum Moderate
Interaction Summary
Calcium citrate might increase aluminum absorption and toxicity.
Read the full Calcium + Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interactionAluminum Hydroxide, Aspirin, Magnesium HydroxideAscriptin
How Aluminum Hydroxide, Aspirin, Magnesium Hydroxide interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumAluminum Moderate
Interaction Summary
Calcium citrate might increase aluminum absorption and toxicity.
Read the full Calcium + Aluminum Hydroxide, Aspirin, Magnesium Hydroxide interactionAluminum Hydroxide, Magnesium Hydroxide (otc Drug)Maalox, Mucogel
How Aluminum Hydroxide, Magnesium Hydroxide (otc Drug) interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumAluminum Moderate
Interaction Summary
Calcium citrate might increase aluminum absorption and toxicity.
Read the full Calcium + Aluminum Hydroxide, Magnesium Hydroxide (otc Drug) interactionAluminum Hydroxide, Magnesium Hydroxide, Simethicone (otc Drug)Mylanta
How Aluminum Hydroxide, Magnesium Hydroxide, Simethicone (otc Drug) interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumAluminum Moderate
Interaction Summary
Calcium citrate might increase aluminum absorption and toxicity.
Read the full Calcium + Aluminum Hydroxide, Magnesium Hydroxide, Simethicone (otc Drug) interactionAluminum, CalciumDomeboro
How Aluminum, Calcium interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumAluminum Moderate
Interaction Summary
Calcium citrate might increase aluminum absorption and toxicity.
Read the full Calcium + Aluminum, Calcium interactionAluminum, Magnesium (otc Drug)Almagel
How Aluminum, Magnesium (otc Drug) interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumAluminum Moderate
Interaction Summary
Calcium citrate might increase aluminum absorption and toxicity.
Read the full Calcium + Aluminum, Magnesium (otc Drug) interactionAluminum, Magnesium Hydroxide (otc Drug)Wingel
How Aluminum, Magnesium Hydroxide (otc Drug) interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumAluminum Moderate
Interaction Summary
Calcium citrate might increase aluminum absorption and toxicity.
Read the full Calcium + Aluminum, Magnesium Hydroxide (otc Drug) interactionAmiloride, HydrochlorothiazideAmil-Co, Amilzide, Moduret 25, Moduretic
How Amiloride, Hydrochlorothiazide interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumThiazide Diuretics Moderate
Interaction Summary
Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Read the full Calcium + Amiloride, Hydrochlorothiazide interactionAmphotericin, TetracyclineMysteclin-F
How Amphotericin, Tetracycline interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumTetracycline Antibiotics Moderate
Interaction Summary
Calcium seems to reduce the absorption of tetracycline antibiotics.
Read the full Calcium + Amphotericin, Tetracycline interactionAspirin, Aluminum Hydroxide, Codeine Phosphate, Magnesium HydroxideAscriptin Codeine #3
How Aspirin, Aluminum Hydroxide, Codeine Phosphate, Magnesium Hydroxide interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumAluminum Moderate
Interaction Summary
Calcium citrate might increase aluminum absorption and toxicity.
Read the full Calcium + Aspirin, Aluminum Hydroxide, Codeine Phosphate, Magnesium Hydroxide interactionAtenolol, ChlortalidoneAtenixCo, Tenoret 50, Totaretic
How Atenolol, Chlortalidone interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumThiazide Diuretics Moderate
Interaction Summary
Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Read the full Calcium + Atenolol, Chlortalidone interactionAtenolol, ChlorthalidoneTenoretic
How Atenolol, Chlorthalidone interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumThiazide Diuretics Moderate
Interaction Summary
Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Read the full Calcium + Atenolol, Chlorthalidone interactionAzilsartan, ChlorthalidoneEdarbyclor
How Azilsartan, Chlorthalidone interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumThiazide Diuretics Moderate
Interaction Summary
Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Read the full Calcium + Azilsartan, Chlorthalidone interactionBenazepril, HydrochlorothiazideLotensin HCT
How Benazepril, Hydrochlorothiazide interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumThiazide Diuretics Moderate
Interaction Summary
Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Read the full Calcium + Benazepril, Hydrochlorothiazide interactionBendroflumethiazideAprinox, Naturetin, Neo-NaClex
How Bendroflumethiazide interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumThiazide Diuretics Moderate
Interaction Summary
Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Read the full Calcium + Bendroflumethiazide interactionBendroflumethiazide, NadololCorzide
How Bendroflumethiazide, Nadolol interacts with Vitamin B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
CalciumThiazide Diuretics Moderate
Interaction Summary
Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Read the full Calcium + Bendroflumethiazide, Nadolol interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Vitamin B-1 100 mg with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.
Calcium
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Brand information
Manufacturer and brand details for Vitamin B-1 100 mg, from the product label.
Major
See all Major products- Name
- Major Pharmaceuticals
- Street Address
- 31778 Enterprise Drive
- City
- Livonia
- State
- MI
- ZipCode
- 48150
- Phone Number
- 1-888-860-5376
Vitamin B-1 100 mg by Major: Common Questions
Does Vitamin B-1 100 mg by Major interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Does calcium cause constipation?
Can I take this if I'm taking levothyroxine for my thyroid?
Is calcium safe during pregnancy?
What is calcium actually used for in this product?
Can very high doses of calcium be harmful?
What's the difference between the active ingredients and the other stuff in this tablet?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Vitamin B-1 100 mg is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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.
The Full Monographs Behind Vitamin B-1 100 mg’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Vitamin B-1 100 mg'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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 62 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.
Calcium 62 references
- Shils M, Olson A, Shike M. Modern Nutrition in Health and Disease. 8th ed. Philadelphia, PA: Lea and Febiger, 1994.
- Hernandez-Avila M, Gonzalez-Cossio T, Hernandez-Avila JE, et al. Dietary calcium supplements to lower blood lead levels in lactating women: a randomized placebo-controlled trial. Epidemiology 2003;14:206-12.. PubMed
- Thys-Jacobs S, Ceccarelli S, Bierman A, et al. Calcium supplementation in premenstrual syndrome: a randomized crossover trial. J Gen Intern Med 1989;4:183-9. PubMed
- Maton PN, Burton ME. Antacids revisited: a review of their clinical pharmacology and recommended therapeutic use. Drugs 1999;57:855-70.
- Clemens JD, Feinstein AR. Calcium carbonate and constipation: a historical review of medical mythopoeia. Gastroenterology 1977;72:957-61. DOI
- Saunders D, Sillery J, Chapman R. Effect of calcium carbonate and aluminum hydroxide on human intestinal function. Dig Dis Sci 1988;33:409-13. PubMed
- Friedman PA, Bushinsky DA. Diuretic effects on calcium metabolism. Semin Nephrol 1999;19:551-6.
- Koo WK, Walters JC, Esterlitz J, et al. Maternal calcium supplementation and fetal bone mineralization. Obstet Gynecol 1999;94:577-82. DOI
- Raman L, Rajalakshmi K, Krishnamachari KAVR, et al. Effect of calcium supplementation to undernourished mothers during pregnancy on the bone density of the neonates. Am J Clin Nutr 1978; 31:466-9. DOI
- Murry JJ, Healy MD. Drug-mineral interactions: a new responsibility for the hospital dietician. J Am Diet Assoc 1991;91:66-73.
- Chan JM, Giovannucci E, Andersson SO, et al. Dairy products, calcium, phosphorous, vitamin D, and risk of prostate cancer. Cancer Causes Control 1998;9:559-66.
- Butner LE, Fulco PP, Feldman G, et al. Calcium carbonate-induced hypothyroidism. Ann Intern Med 2000:132:595. PubMed
- Schneyer CR. Calcium carbonate and reduction of levothyroxine efficacy. JAMA 1998;279:750. PubMed
- Moser LR, Smythe MA, Tisdale JE. The use of calcium salts in the prevention and management of verapamil-induced hypotension. Ann Pharmacother 2000;34:622-9. PubMed
- Singh N, Singh PN, Hershman JM. Effect of calcium carbonate on the absorption of levothyroxine. JAMA 2000;283:2822-5. PubMed
- Kahela P, Anttila M, Tikkanen R, Sundquist H. Effect of food, food constituents and fluid volume on the bioavailability of sotalol. Acta Pharmacol Toxicol (Copenh) 1979;44:7-12.. PubMed
- Pletz MW, Petzold P, Allen A, et al. Effect of calcium carbonate on bioavailability of orally administered gemifloxacin. Antimicrob Agents Chemother 2003;47:2158-60.. PubMed
- Bar-Or D, Yoel G. Calcium and calciferol antagonize effect of verapamil in atrial fibrillation. Br Med J 1981;282:1585-6.
- Decktor DL, Robinson M, Maton PN, et al. Effects of aluminum/magnesium hydroxide and calcium carbonate on esophageal and gastric pH in subjects with heartburn. Am J Ther 1995;2:546-52. PubMed
- Simoneau G. Absence of rebound effect with calcium carbonate. Eur J Drug Metab Pharmacokinet 1996;21:351-7. PubMed
- Peters ML, Leonard M, Licata AA. Role of alendronate and risedronate in preventing and treating osteoporosis. Cleve Clin J Med 2001;68:945-51. PubMed
- Bourke JF, Mumford R, Whittaker P, et al. The effects of topical calcipotriol on systemic calcium homeostasis in patients with chronic plaque psoriasis. J Am Acad Dermatol 1997;37:929-34.
- Gueguen L, Pointillart A. The bioavailability of dietary calcium. J Am Coll Nutr 2000;19:119s-136s. PubMed
- Vella A, Gerber TC, Hayes DL, Reeder GS. Digoxin, hypercalcaemia, and cardiac conduction. Postgrad Med J 1999;75:554-6. PubMed
- Bania TC, Blaufeux B, Hughes S, et al. Calcium and digoxin vs. calcium alone for severe verapamil toxicity. Acad Emerg Med 2000;7:1089-96. PubMed
- Tseng M, Breslow RA, Graubard BI, Ziegler RG. Dairy, calcium, and vitamin D intakes and prostate cancer risk in the National Health and Nutrition Examination Epidemiologic Follow-up Study cohort. Am J Clin Nutr 2005;81:1147-54. PubMed
- Weingarten MA, Zalmanovici A, Yaphe J. Dietary calcium supplementation for preventing colorectal cancer and adenomatous polyps. Cochrane Database Syst Rev 2004;(1):CD003548. PubMed
- Tavani A, Bertuccio P, Bosetti C, et al. Dietary intake of calcium, vitamin D, phosphorus and the risk of prostate cancer. Eur Urol 2005;48:27-33. PubMed
- Giovannucci E, Liu Y, Stampfer MJ, Willett WC. A prospective study of calcium intake and incident and fatal prostate cancer. Cancer Epidemiol Biomarkers Prev 2006;15:203-10. PubMed
- Rocephin (ceftriaxone) and calcium interaction. Pharmacist's Letter / Prescriber's Letter 2007;23(10):231005.
- Bolland MJ, Barber PA, Doughty RN, et al. Vascular events in healthy older women receiving calcium supplementation: randomised control trial. BMJ 2008;336:262-6.
- Bolland MJ, Avenell A, Baron JA, et al. Effect of calcium supplements on risk of myocardial infarction and cardiovascular events: meta-analysis. BMJ 2010;341:c3691. PubMed
- Calcium supplementation and vascular events. Pharmacist's Letter / Prescriber's Letter 2008;24(3):240306.
- Dietary reference intakes for calcium and vitamin D. Institute of Medicine, November 30, 2010. Available at: http://www.iom.edu/~/media/Files/Report%20Files/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D/Vitamin%20D%20and%20Calcium%202010%20Repo
- Coburn JW, Mischel MG, Goodman WG, et al. Calcium citrate markedly enhances aluminum absorption from aluminum hydroxide. Am J Kidney Dis. 1991;17(6):708-11. PubMed
- Bradley JS, Wassel RT, Lee L, et al. Intravenous ceftriaxone and calcium in the neonate: assessing the risk for cardiopulmonary adverse events. Pediatrics. 2009;123(4):e609-13. PubMed
- Kays MB, Overholser BR, Mueller BA, et al. Effects of sevelamer hydrochloride and calcium acetate on the oral bioavailability of ciprofloxacin. Am J Kidney Dis. 2003;42(6):1253-9. PubMed
- Neuhofel, A. L., Wilton, J. H., Victory, J. M., Hejmanowsk, L. G., and Amsden, G. W. Lack of bioequivalence of ciprofloxacin when administered with calcium-fortified orange juice: a new twist on an old interaction. J Clin Pharmacol. 2002;42(4):461-466. DOI
- Dickinson, H. O., Nicolson, D. J., Cook, J. V., Campbell, F., Beyer, F. R., Ford, G. A., and Mason, J. Calcium supplementation for the management of primary hypertension in adults. Cochrane.Database.Syst.Rev. 2006;(2):CD004639. PubMed
- Jones, B. J. and Twomey, P. J. Requesting patterns for serum calcium concentration in patients on long-term lithium therapy. Int J Clin Pract. 2009;63(1):170-172. PubMed
- Levine, M., Nikkanen, H., and Pallin, D. J. The effects of intravenous calcium in patients with digoxin toxicity. J Emerg.Med. 2011;40(1):41-46. PubMed
- Castelo-Branco, C., Ciria-Recasens, M., Cancelo-Hidalgo, M. J., Palacios, S., Haya-Palazuelos, J., Carbonell-Abello, J., Blanch-Rubio, J., Martinez-Zapata, M. J., Manasanch, J., and Perez-Edo, L. Efficacy of ossein-hydroxyapatite complex compared with ca
- Li K, Kaaks R, Linseisen J, Rohrmann S. Associations of dietary calcium intake and calcium supplementation with myocardial infarction and stroke risk and overall cardiovascular mortality in the Heidelberg cohort of the European Prospective Investigation i
- Chung M, Tang AM, Fu Z. Calcium Intake and Cardiovascular Disease Risk: An Updated Systematic Review and Meta-analysis. Ann Intern Med. 2016 Oct 25. PubMed
- Nolan CR, Califano JR, Butzin CA. Influence of calcium acetate or calcium citrate on intestinal aluminum absorption. Kidney Int. 1990;38(5):937-41. PubMed
- Lewis JR, Radavelli-Bagatini S, Rejnmark L, et al. The effects of calcium supplementation on verified coronary heart disease hospitalization and death in postmenopausal women: a collaborative meta-analysis of randomized controlled trials. J Bone Miner Res PubMed
- Jalloh MA, Gregory PJ, Hein D, et al. Dietary supplement interactions with antiretrovirals: a systematic review. Int J STD AIDS. 2017 Jan;28(1):4-15. PubMed
- Lappe J, Watson P, Travers-Gustafson D, Recker R, Garland C, Gorham E, Baggerly K, McDonnell SL. Effect of Vitamin D and Calcium Supplementation on Cancer Incidence in Older Women: A Randomized Clinical Trial. JAMA. 2017 Mar 28;317(12):1234-1243. PubMed
- Grove ML, Cook D. Calcium and heart attacks. Doesn't apply to most calcium prescriptions. BMJ. 2010;341:c5003. PubMed
- Insentress [package insert]. Whitehouse Station, NJ: Merck Sharp & Dohme Corp.; 2014.
- Roberts JL, Kiser JJ, Hindman JT, Meditz AL. Virologic failure with a raltegravir-containing antiretroviral regimen and concomitant calcium administration. Pharmacotherapy 2011;31(10):298e-302e. DOI
- Vitekta [package insert]. Foster City, CA: Gilead Sciences, Inc.; 2014.
- Storan ER, O'Gorman SM, Murphy A, Laing M. Case Report of Calciphylaxis Secondary to Calcium and Vitamin D<sub>3</sub> Supplementation. J Cutan Med Surg. 2017;21(2):162-163. DOI
- Jenkins DJA, Spence JD, Giovannucci EL, et al. Supplemental vitamins and minerals for CVD prevention and treatment. J Am Coll Cardiol 2018;71(22):2570-84. PubMed
- Borkenhagen JF, Connor EL, Stafstrom CE. Neonatal hypocalcemic seizures due to excessive maternal calcium ingestion. Pediatr Neurol 2013;48(6):469-71. PubMed
- WHO recommendations on antenatal care for a positive pregnancy experience. Geneva: World Health Organization; 2016 (http://www.who.int/reproductivehealth/publications/maternal_perinatal_health/ anc-positive-pregnancy-experience/en/).
- Aune D, Navarro Rosenblatt DA, Chan DS, et al. Dairy products, calcium, and prostate cancer risk: a systematic review and meta-analysis of cohort studies. Am J Clin Nutr. 2015;101(1):87-117. PubMed
- Lan T, Park Y, Colditz GA, et al. Adolescent dairy product and calcium intake in relation to later prostate cancer risk and mortality in the NIH-AARP Diet and Health Study. Cancer Causes Control. 2020;31(10):891-904. PubMed
- Zhang Y, Li Y, Liu J, et al. Association of Vitamin D or Calcium Supplementation with Cardiovascular Outcomes and Mortality: A Meta-Analysis with Trial Sequential Analysis. J Nutr Health Aging 2021;25(2):263-270. PubMed
- Myung SK, Kim HB, Lee YJ, Choi YJ, Oh SW. Calcium Supplements and Risk of Cardiovascular Disease: A Meta-Analysis of Clinical Trials. Nutrients 2021;13(2):368. PubMed
- Hetaimish B. Neonatal Calcinosis Cutis After Treatment of Hypocalcemia with Calcium Gluconate: A Report of 2 Cases. Am J Case Rep 2024;25:e943397. PubMed
- US Food and Drug Administration (FDA). Biktarvy Prescribing Information. October 2024. Available at: https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/210251Orig1s020lbl.pdf. Accessed July 16, 2025.
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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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