Major interaction on record — check this product against your medications before combining. Based on 2 of 6 ingredients. Check your meds →
Dietary supplement

MOAB Unflavored Ingredients & Drug Interactions

by Redcon1

MOAB Unflavored label
See full label image
Powder Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking MOAB Unflavored 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

MOAB Unflavored is a dietary supplement by Redcon1 with 6 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, 778 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Vitamin D3, Calcium. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against MOAB Unflavored by Redcon1

Ask about any prescription or over-the-counter medication and we check it for interactions with MOAB Unflavored by Redcon1 — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of MOAB Unflavored by Redcon1

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.
  • No proprietary blends here — you can verify the dose of every single component.

MOAB Unflavored contains 6 active ingredients. The main ones are calcium and vitamin D3, both essential nutrients for bone and muscle health.

The product also contains HICA (a metabolite linked to muscle breakdown), calcium B-hydroxy B-methylbutyrate monohydrate (a compound studied for lean muscle support), epicatechin (a plant compound), and AstraGin (a proprietary absorption enhancer). Three inactive ingredients—maltodextrin, calcium silicate, and silicon dioxide—are added as fillers and flow agents.

Does it work?

Insufficient 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
Insufficient

There isn't enough reliable clinical evidence to rate this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: muscle building and strength for athletes.
  • We looked for evidence on: Athletic performance, Exercise-induced muscle damage, Muscle strength, Hypertrophy, Lean mass gain, Anabolic support.
  • The closest evidence on file: Calcium is rated "Insufficient Reliable Evidence To Rate" for Exercise-induced muscle damage (Natural Medicines).
  • Also on file: Vitamin D is rated "Insufficient Reliable Evidence To Rate" for Athletic performance, Muscle strength, Exercise-induced muscle damage.

Calcium in this product is effective for kidney failure, upset stomach (dyspepsia), low blood calcium (hypocalcemia), high potassium (hyperkalemia), and likely effective for osteoporosis. Vitamin D3 is effective for familial hypophosphatemia, soft-bone disease in kidneys (renal osteodystrophy), rickets, and low parathyroid hormone (hypoparathyroidism), and it's effective for soft-bone disease without kidney failure (osteomalacia).

For the other ingredients—HICA, epicatechin, and AstraGin—the effectiveness data we hold doesn't establish their benefits, so you'd want to check the product's own research or ask your doctor or pharmacist whether they align with your goals.

The evidence, ingredient by ingredient Calcium Vitamin D

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 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Calcium and vitamin D3 are generally well tolerated at recommended doses, though high doses can cause problems over time. Calcium's most common side effects are belching, constipation, diarrhea, bloating, and stomach upset.

Rare serious concerns include kidney stones and a condition called calciphylaxis. Some research suggests very high calcium intake (over 1,500–2,000 mg daily) may be linked to higher prostate cancer risk and possibly increased heart disease risk, though other studies dispute this.

Vitamin D toxicity from excessive doses can cause high blood calcium with symptoms like weakness and kidney problems. In pregnancy, adequate calcium is important but stay within recommended amounts unless your doctor advises otherwise.

For breastfeeding, calcium and vitamin D at recommended levels are fine, though check with your provider if you're taking higher amounts.

Side effects, ingredient by ingredient Calcium Vitamin D

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?
  • 2 of the 2 matched ingredients can interact with medications — Calcium, Vitamin D.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: heart-rhythm medications; lithium.
  • For scale: 779 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.

Double-check the following medication types before taking this product, worst first: HIV integrase inhibitors (dolutegravir, elvitegravir) and cephalosporin antibiotics given by IV (ceftriaxone)—these have Major interactions. Then check the other HIV drug raltegravir (Isentress), thyroid hormone (levothyroxine/Synthroid), the heart drugs diltiazem and verapamil, the rhythm drug digoxin, the beta-blocker sotalol, the statin atorvastatin, thiazide diuretics, calcipotriene, and CYP3A4-metabolized drugs.

If you take any of these, talk with your doctor or pharmacist about spacing or alternatives.

Check your own medication Run your meds through the checker above

The bottom line

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

This product is geared toward people interested in muscle and bone support through calcium and vitamin D3. If you take any HIV medications (especially integrase inhibitors), thyroid hormone, heart-rhythm drugs, or antibiotics like ceftriaxone, you'll need to space doses carefully or avoid this product—talk with your doctor or pharmacist first.

Even at recommended doses, it's generally well tolerated, but high intakes over time carry rare serious risks. Run your full medication list through the interaction checker on this page before starting.

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

Assessment coverage: 3 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 16, 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

At a glance

General information

Key facts about MOAB Unflavored, straight from the product label.

Brand Redcon1
Barcode (UPC) 810044570397
Net contents 5.29 Ounce(s); 150 Gram(s)
Market status On market
Date entered into DSLD Jun 16, 2022
DSLD ID 269183
Product type Other Combinations
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
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 MOAB Unflavored by Redcon1, 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:
5 Gram(s)
Maximum serving Sizes:
5 Gram(s)
Servings per container
30
UPC/BARCODE
810044570397
IngredientAmount% DV
Calcium390 mg30%
Vitamin D325 mcg125%
HICA1000 mg--
Calcium B-Hydroxy B-Methylbutyrate Monohydrate3000 mg--
Epicatechin300 mg--
AstraGin50 mg--

Other ingredients: Maltodextrin, Calcium Silicate, Silicon Dioxide

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

The objective: When you're looking for size and strength, it's hard to beat the power of leucine. Unleash the power of some of the strongest leucine metabolites with moab. This potent, natural anabolic mass builder and nitric oxide boosting amplifier will set the stage for the best possible growth environment.

Suggested/Recommended/Usage/Directions

Moab Suggested Use: For best use, mix (1) scoop with 8-12 ounces of water or your favorite beverage, 30 minutes prior to training. For added intensity, stack Moab with total war and big noise for the ultimate pre-workout stack.

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.

Seals/Symbols

Nutravigilance Verified Supplement Safety Solutions

Formulation

Preworkout Mother of all builders Muscle builder

Muscle volume Recovery Lean muscle

FDA Statement of Identity

Dietary Supplement

Precautions

Warning: This product is intended to be consumed by healthy adults 18 years of age or older.

Do not use if you are pregnant, nursing, taking any prescription or over-the-counter medications or supplements, or if you have or suspect you may have a medical condition, including but not limited to: high or low blood pressure, cardiac arrhythmia, stroke, heart, liver or kidney disease, seizure disorder, thyroid disease, psychiatric disease, diabetes, prostate enlargement or if you are taking a MAO Inhibitor.

Do not use if you are prone to dehydration or exposed to excessive heat. As with any dietary supplement, consult a healthcare professional before using this product. Discontinue 2 weeks prior to surgery. Immediately discontinue use and consult a healthcare professional if you experience any adverse reactions.

Keep out of reach of children.

Brand IP Statement(s)

myHMB Nutritional uses of Calcium B-Hydroxy B-Methylbutyrate Monohydrate (HMB) and Vitamin D are licensed to Redcon1, LLC under U.S. Patent #8,815,280, #9,259,430, #9,539,224 and #9,707,241.

Storage

Store at 59-86 degrees F (15-30 degrees C). Protect from light and moisture.

General Statements

Product does not completely fill container. Settling occurs in shipping.

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

See for yourself

MOAB Unflavored by Redcon1 label

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

MOAB Unflavored 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 MOAB Unflavored by Redcon1

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size5 Gram(s) Dosage formPowder Servings per container30 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 with
168 drugs
390 mg per serving

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 & interactions

Vitamin D3

Interacts with
715 drugs
25 mcg per serving Form: Cholecalciferol

Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people,...

Vitamin D3 monograph & interactions

HICA

1000 mg per serving

Calcium B-Hydroxy B-Methylbutyrate Monohydrate

Interacts with
168 drugs
3000 mg per serving Form: myHMB

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 B-Hydroxy B-Methylbutyrate Monohydrate monograph & interactions

Epicatechin

300 mg per serving Form: Green Tea extract

AstraGin

50 mg per serving Form: Astragalus extract, Panax notoginseng extract

Other (inactive) ingredients: Maltodextrin, Calcium Silicate, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

MOAB Unflavored by Redcon1 Drug Interactions

Want to check YOUR meds against MOAB Unflavored?

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
778Drugs
7 Major 146 Moderate 625 Minor

Ingredients driving the most interactions

Vitamin D3 715
Calcium 168

Individual Drug Interactions

The ingredients in MOAB Unflavored interact with 778 drugs. Click any drug to see the details.

2 of the 6 ingredients in MOAB Unflavored interact with drugs. Each result below shows which ingredient is responsible. Vitamin D3 Calcium

Each ingredient & the kinds of drugs it affects

For each ingredient in MOAB Unflavored 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 D38 drug types · 715 drugs

Aluminum

Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
The protein that transports calcium across the intestinal wall can also bind and transport aluminum. This protein is stimulated by vitamin D, which may therefore increase aluminum absorption. This mechanism may contribute to increased aluminum levels and toxicity in people with renal failure, when they take vitamin D and aluminum-containing phosphate binders chronically.

Likelihood Probable Evidence B
Atorvastatin (Lipitor)

Vitamin D might reduce absorption of atorvastatin.
A small, low-quality clinical study shows that taking vitamin D reduces levels of atorvastatin and its active metabolites by up to 55%. However, while atorvastatin levels decreased, total cholesterol, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol levels did not substantially change. Atorvastatin is metabolized in the gut by CYP3A4 enzymes, and researchers theorized that vitamin D might induce CYP3A4, causing reduced levels of atorvastatin. However, this proposed mechanism was not specifically studied.

Likelihood Probable Evidence B
Calcipotriene (Dovonex)

Taking calcipotriene with vitamin D increases 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 vitamin D supplements might increase the risk of hypercalcemia.

Likelihood Probable Evidence D
Digoxin (Lanoxin)

Theoretically, hypercalcemia induced by high-dose vitamin D can increase the risk of arrhythmia from digoxin.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and digoxin concurrently.

Likelihood Possible Evidence D
Diltiazem (Cardizem, Others)

Theoretically, hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of diltiazem for arrhythmia.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically this could also occur with diltiazem. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and diltiazem concurrently.

Likelihood Probable Evidence B
Thiazide Diuretics

Theoretically, taking thiazide diuretics and high-dose vitamin D can increase the risk of hypercalcemia.
Thiazide diuretics decrease urinary calcium excretion, which could lead to hypercalcemia if vitamin D supplements are taken concurrently. This has been reported in people being treated with vitamin D for hypoparathyroidism, and also in elderly people with normal parathyroid function who were taking a thiazide, vitamin D, and calcium-containing antacids daily.

Likelihood Probable Evidence D
Verapamil (Calan, Others)

Hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of verapamil for arrhythmia.
Hypercalcemia due to high doses of vitamin D can reduce the effectiveness of verapamil in atrial fibrillation. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and verapamil concurrently.

Likelihood Probable Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
There is some concern that vitamin D might induce CYP3A4. In vitro research suggests that vitamin D induces CYP3A4 transcription. Additionally, observational research has found that increased UV light exposure and serum vitamin D levels are associated with decreased serum levels of CYP3A4 substrates such as tacrolimus and sirolimus, while no association between UV light exposure or vitamin D levels and levels of mycophenolic acid, a non-CYP3A4 substrate, was found. A small, low-quality clinical study shows that taking vitamin D reduces levels of the CYP3A4 substrate atorvastatin and its active metabolites by up to 55%; however, the clinical effects of atorvastatin were not reduced. While researchers theorized that vitamin D might induce CYP3A4, this proposed mechanism was not specifically studied.

Likelihood Possible Evidence D
Vitamin D3 full monograph & interactions

Calcium18 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 full monograph & interactions
The maker

Brand information

Manufacturer and brand details for MOAB Unflavored, from the product label.

Redcon1

See all Redcon1 products
Name
Redcon1, LLC
Street Address
701 Park of Commerce Blvd., Suite 101
City
Boca Raton
State
FL
ZipCode
33487
Phone Number
1(855)733-2661
Web Address
www.Redcon1.com
Pharmacist Counseling Corner

MOAB Unflavored by Redcon1: Common Questions

Does MOAB Unflavored by Redcon1 interact with any medications?
Yes. Based on its ingredients, MOAB Unflavored has a known interaction with 778 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?
MOAB Unflavored 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.
What is calcium B-hydroxy B-methylbutyrate monohydrate?
It's a compound that combines calcium with a metabolite called HMB (beta-hydroxy beta-methylbutyrate), which is studied for its role in supporting lean muscle. It acts like the calcium in the product—so it carries the same drug interactions.
Can I take this if I'm on levothyroxine for my thyroid?
Calcium in this product reduces how much levothyroxine your body absorbs, which can make it less effective. You'd need to space the two at least 4 hours apart. Check with your doctor or pharmacist to see if that works with your routine, or whether you should skip this product.
Does this product have fillers?
Yes. It contains maltodextrin, calcium silicate, and silicon dioxide as inactive ingredients—these help with texture and flow of the powder. The active ingredients are the calcium, vitamin D3, and the others listed.
Is it safe to take this while pregnant?
Calcium at recommended amounts is likely safe and important in pregnancy, but very high doses can cause problems. Vitamin D at recommended doses is likely safe in pregnancy, though it may carry some risk at high doses. Stay within recommended amounts and talk with your doctor to make sure it fits your pregnancy plan.
Can this product interact with my medications?
Yes, calcium and vitamin D3 interact with quite a few medications—HIV drugs, antibiotics, thyroid hormone, heart drugs, statins, and others. Search your exact medications using the tool on this page to see if any need adjustment, and talk with your doctor or pharmacist before starting.
What are the most common side effects?
Belching, constipation, diarrhea, bloating, and stomach upset are the most common, especially if you take more than recommended. Serious side effects like kidney stones are rare.

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.

MOAB Unflavored label
Go deeper

The Full Monographs Behind MOAB Unflavored’s Ingredients

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

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 D

Interacts with 715 drugs

Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people, especially those with low sun exposure,...

Read the full Vitamin D monograph →
Sources

Sources & How We Checked

MOAB Unflavored'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 88 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
  1. Shils M, Olson A, Shike M. Modern Nutrition in Health and Disease. 8th ed. Philadelphia, PA: Lea and Febiger, 1994.
  2. 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
  3. 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
  4. Maton PN, Burton ME. Antacids revisited: a review of their clinical pharmacology and recommended therapeutic use. Drugs 1999;57:855-70.
  5. Clemens JD, Feinstein AR. Calcium carbonate and constipation: a historical review of medical mythopoeia. Gastroenterology 1977;72:957-61. DOI
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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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