Major interaction on record — check this product against your medications before combining. Based on 7 of 9 ingredients. Check your meds →
Dietary supplement

Healthy Cholesterol Formula Ingredients & Drug Interactions

by GNC Preventive Nutrition

Healthy Cholesterol Formula label
See full label image
Other (e.g. Tea Bag) 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 Healthy Cholesterol Formula 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

Healthy Cholesterol Formula is a dietary supplement by GNC Preventive Nutrition with 9 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, 1,279 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Chinese Skullcap root extract, Black Tea leaf extract, Cutch Tree wood & bark extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Healthy Cholesterol Formula by GNC Preventive Nutrition

Ask about any prescription or over-the-counter medication and we check it for interactions with Healthy Cholesterol Formula by GNC Preventive Nutrition — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Healthy Cholesterol Formula by GNC Preventive Nutrition

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

From our pharmacy team — supplement deep dive

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

What’s inside

Partial disclosure
Ingredient Transparency · database check
Partial

Most active ingredients list an amount, but at least one is hidden in a blend or missing.

Why this rating?
  • The label discloses an exact amount for 7 of its 9 active ingredients.
  • “Cholesterol Support Blend” is a proprietary blend — the label doesn't break down how much of each component you get.
  • “Antioxidant Support Complex” is a proprietary blend — the label doesn't break down how much of each component you get.
  • “Inflammatory Response Support Blend” is a proprietary blend — the label gives one combined amount (62.50 mg) without saying how much of each component you get.

Healthy Cholesterol Formula contains 9 ingredients. The active ones are zeaxanthin and lutein (both yellow pigments that concentrate in the eye), calcium (for bone and metabolic health), coenzyme Q10 (an antioxidant), betaine (which we could not check), black tea leaf extract (containing caffeine), Chinese skullcap root extract, and cutch tree wood and bark extract.

Two blends — CardioAid Phytosterols and a Cholesterol Support Blend — are listed as ingredient groups. The product also contains inactive ingredients (dicalcium phosphate and cellulose) as binders and fillers.

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: manage cholesterol levels and support heart health.
  • We looked for evidence on: Dyslipidemia, Cardiovascular disease (CVD), Coronary heart disease (CHD), Atherosclerosis, Angina, Congestive heart failure (CHF) — and 4 related terms.
  • The strongest evidence on file: Coenzyme Q10 is rated "Likely Effective" for Coenzyme Q10 deficiency (Natural Medicines).
  • Also on file: Coenzyme Q10 is rated "Possibly Effective" for Congestive heart failure (CHF).
  • Also on file: Calcium is rated "Ineffective" for Cardiovascular disease (CVD).

The evidence for these ingredients is mixed. Calcium and lutein are both backed by solid research — calcium for bone health and lutein for age-related macular degeneration (the eye disease AMD).

Coenzyme Q10 appears possibly effective for heart failure, migraines, and fibromyalgia. Black tea has possibly effective evidence for heart attack prevention.

For zeaxanthin and AMD, the evidence is also possibly effective, though for age-related cognitive decline and several other uses, the data we hold is insufficient to rate. Chinese skullcap and cutch tree extract lack established evidence in our data — we have no rating for their claimed cholesterol or other benefits in this formula.

The evidence, ingredient by ingredient Calcium Black Tea Zeaxanthin Lutein Coenzyme Q10 Baikal Skullcap Catechu

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 6 of the 7 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 7 of 7.
  • General safety write-ups exist for 7 of 7.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most ingredients here are generally well tolerated at typical doses. Calcium, coenzyme Q10, and lutein are generally safe orally when used as directed.

Black tea is safe in moderate amounts, though its caffeine can cause jitteriness, insomnia, and stomach upset in sensitive people. Chinese skullcap and cutch tree extract have limited human safety data; digestive upset (nausea, diarrhea, abdominal pain) has been reported with skullcap.

A specific product combining Baikal skullcap and catechu extracts was recalled in 2017 due to reports of liver and lung injury — though this product's formulation differs, it's a caution flag for the category. Very high calcium doses (over 1500 mg daily) have been weakly associated with increased prostate cancer and heart disease risk in some studies, though this remains debated.

Zeaxanthin and lutein in pregnancy are likely safe, but supplement data in pregnancy are limited for zeaxanthin — use caution. Black tea caffeine should be limited in pregnancy.

Calcium is safe in pregnancy at recommended amounts. Coenzyme Q10 has insufficient pregnancy data.

Chinese skullcap and cutch tree extract lack safety data and should be avoided in pregnancy and while breastfeeding.

Side effects, ingredient by ingredient Calcium Black Tea Zeaxanthin Lutein Coenzyme Q10 Baikal Skullcap Catechu

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?
  • 6 of the 7 matched ingredients can interact with medications — Catechu, Calcium, Baikal Skullcap, Coenzyme Q10, Black Tea, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications; lithium.
  • For scale: 1,279 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 this product, double-check any of these with your pharmacist: HIV antivirals (dolutegravir and elvitegravir — the calcium here blocks their absorption significantly); blood thinners like warfarin (both calcium and black tea may reduce effectiveness); thyroid medication levothyroxine (calcium blocks it); diabetes drugs (zeaxanthin and skullcap may lower blood sugar); blood pressure medications (coenzyme Q10, black tea, skullcap, and catechu may lower it further); heart rhythm drugs like sotalol; the antibiotic ceftriaxone if given intravenously; epilepsy medication valproate (caffeine in black tea may interfere); and antipsychotic clozapine (caffeine may worsen symptoms).

Check your own medication Run your meds through the checker above

The bottom line

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

This formula's ingredients — particularly the lutein and zeaxanthin for eye health — are standard cholesterol and cardiovascular support tools. But the calcium and black tea interact significantly with common medications.

If you take any prescription drugs, especially blood thinners (warfarin), thyroid medication, HIV antivirals, diabetes drugs, or heart medications, check your exact medications with the tool on this page before starting. Pregnant or nursing?

Talk to your pharmacist first, especially about the skullcap and cutch extracts.

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

Assessment coverage: 7 of 9 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 25, 2013.

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 Healthy Cholesterol Formula, straight from the product label.

Brand GNC Preventive Nutrition
Net contents 90 Caplet(s)
Market status Off market
Date entered into DSLD Feb 25, 2013
DSLD ID 18451
Product type Other Combinations
Supplement form Other (e.g. Tea Bag)
Dietary claims / uses All Other, Approved Health, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar 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 Healthy Cholesterol Formula by GNC Preventive Nutrition, 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:
3 Caplet(s)
Maximum serving Sizes:
3 Caplet(s)
Servings per container
30
IngredientAmount% DV
Zeaxanthin200 mcg--
Calcium222 mg22%
Lutemax 2020 Lutein1000 mg--
Coenzyme Q-10100 mg--
Betaine200 mg--
Black Tea leaf extract1000 mg--
CardioAid Phytosterols1200 mg--
Cholesterol Support Blend0 NP--
Chinese Skullcap root extract0 NP--
Cutch Tree wood & bark extract0 NP--
Antioxidant Support Complex0 NP--
Inflammatory Response Support Blend62.5 mg--

Other ingredients: Dicalcium Phosphate, Cellulose

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.
Precautions

Discontinue use two weeks prior to surgery.

WARNING: Consult your physician prior to using this product if you are pregnant, nursing, taking medication, or have a medical condition.

KEEP OUT OF REACH OF CHILDREN.

Brand IP Statement(s)

GNC Preventative Nutrition(R) products have been scientifically developed utilizing the expertise of the GNC Medical Advisory Board.

CardioAid(TM) and the CardioAid(TM) logo are trademarks of Archer Daniels Midland Company. Lutemax 2020(TM) is a trademark of OmniActive Health Technologies.

Preventative Nutrition(R) Healthy Cholesterol Formula contains potent blend of clinically studied ingredients, additional key nutrients and a lifestyle program to help manage cholesterol levels and support hearth health.*

General Statements

Each premium formula is designed to be used in conjunction with your physician recommended healthcare regimen. This line of products is precisely formulated to provide clinical strength ingredients and additional nutrients that address key health concerns.

DEVELOPED WITH AND ENDORSED BY GNC MEDICAL ADVISORY BOARD ADVANCED KNOWLEDGE FOR BETTER HEALTH The GNC Medical Advisory Board utilizes their in-depth medical knowledge and experience to aid in the creation and ongoing development of GNC products, helping GNC stay on the forefront of product innovation and delivering on our commitment to helping you LIVE WELL.

GNC QUALITY COMMITMENT For more than 75 years, GNC has been the leader in the development and manufacture of dietary supplements and is committed to producing the most superior products. We use only the highest quality ingredients manufactured under the strictest quality controls. Every raw material used is tested to ensure its purity and potency. Each product is dated and then shipped immediately to our stores to ensure that you are purchasing the freshest supplements available.

This multi-action formula supplies key nutrients that can help block the absorption of cholesterol, promote cellular health, and help support heart health.*

^Foods containing at least 0.5 g per serving of phytosterols eaten with meals or snacks for a daily total intake of 2 g as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease. Preventative Nutrition(R) Healthy Cholesterol Formula supplies 1.2 g of phytosterols. The proprietary blend of flavonoids from Acacia catechu and Scutellaria baicalensis extracts has been shown to act upon metabolic processes in the body related to supporting a healthy inflammatory response.

PHYSICIAN FORMULATED NUTRITION SOLUTIONS Supports normal, healthy cholesterol & triglyceride levels with clinically studied black tea extract* Features potent phytosterols, which may reduce the risk of heart disease^ Provides CoQ-10 for powerful cardiovascular antioxidant support*

Meets USP <2040> disintegration. Conforms to USP <2091> for weight.

Formulation

No Sugar, No Artificial Colors, No Artificial Flavors, No Preservatives, Sodium Free, No Wheat, No Gluten, No Dairy, Yeast Free.

Formula

Cholesterol Support-Features a powerful blend of black tea extract that is clinically shown to support normal, healthy cholesterol and triglyceride levels and heart health.* Phytosterols work by blocking cholesterol absorption from foods and may reduce the risk of heart disease.*^ Antioxidant Support-Provides trimethylglycine and CoQ-10 to help protect cells from oxidative damage.* CoQ-10 is a powerful cardiovascular antioxidant and an essential component of the heart's energy producing system.* Inflammatory Response Support-Contains Acacia catechu and Scutellaria baicalensis, powerful antioxidant herbs that support a healthy response to inflammation.*

Total Caffeine=60 mg

FDA Disclaimer Statement

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

FDA Statement of Identity

DIETARY SUPPLEMENT

Seals/Symbols

PHYSICIAN ENDORSED

CardioAid(TM) plant sterols

Lutemax 2020(TM) LUTEIN & ZEAXANTHIN

General

CODE 714412 GNG

Suggested/Recommended/Usage/Directions

Directions: As a dietary supplement, take three caplets daily with food.

Storage

Store in a cool, dry place.

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

See for yourself

Healthy Cholesterol Formula by GNC Preventive Nutrition label

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

Healthy Cholesterol Formula 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 Healthy Cholesterol Formula by GNC Preventive Nutrition

These are the 9 active ingredients this product is made of. Select any to open its full monograph.

Serving size3 Caplet(s) Dosage formOther (e.g. Tea Bag) 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
222 mg per serving Form: Dicalcium Phosphate

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

Cholesterol Support Blend

0 NP per serving

Antioxidant Support Complex

0 NP per serving

Inflammatory Response Support Blend

62.5 mg per serving

Other (inactive) ingredients: Dicalcium Phosphate, Cellulose. These complete the product’s ingredient list but are not active constituents.

Interaction report

Healthy Cholesterol Formula by GNC Preventive Nutrition Drug Interactions

Want to check YOUR meds against Healthy Cholesterol Formula?

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
1,279Drugs
15 Major 1,037 Moderate 227 Minor

Ingredients driving the most interactions

Chinese Skullcap root extract 946
Black Tea leaf extract 694
Cutch Tree wood & bark extract 475
Coenzyme Q-10 198
Calcium 168

Individual Drug Interactions

The ingredients in Healthy Cholesterol Formula interact with 1,279 drugs. Click any drug to see the details.

6 of the 9 ingredients in Healthy Cholesterol Formula interact with drugs. Each result below shows which ingredient is responsible. Chinese Skullcap root extract Black Tea leaf extract Cutch Tree wood & bark extract Coenzyme Q-10 Calcium Zeaxanthin

Each ingredient & the kinds of drugs it affects

For each ingredient in Healthy Cholesterol Formula 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.

Chinese Skullcap root extract12 drug types · 946 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, Baikal skullcap might increase the risk of bleeding when used concomitantly with anticoagulant and antiplatelet drugs.
Preliminary clinical research suggests that taking capsules containing a combination of astragalus, goldthread, and Baikal skullcap daily for 4 weeks inhibits platelet aggregation; the effect seems to be similar to that of aspirin 50 mg daily. It is unclear if this effect is due to Baikal skullcap, other ingredients, or the combination.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, concomitant use of Baikal skullcap with antidiabetes drugs might enhance blood glucose lowering effects.
Baicalein, a constituent of Baikal skullcap, has alpha-glucosidase inhibitory activity in vitro. Animal research also suggests that Baikal skullcap enhances the antidiabetic effects of metformin. However, in a small human study, taking Baikal skullcap extract did not enhance the antidiabetic effects of metformin, although it did modestly lower glucose levels during an oral glucose tolerance test (OGTT). Until more is known, use cautiously.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, concomitant use of Baikal skullcap with antihypertensive drugs might have additive effects and increase the risk of hypotension.
Animal research suggests that baicalein, a constituent of Baikal skullcap, might lower blood pressure.

Likelihood Possible Evidence D
Antithyroid Drugs

Theoretically, concomitant use of Baikal skullcap and antithyroid drugs may result in additive activity and increase the risk of hypothyroidism.
In an animal hyperthyroid model, Baikal skullcap improved levels of triiodothyronine (T3), thyroxine (T4), and thyroid stimulating hormone (TSH). The clinical significance of this effect is unclear.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, Baikal skullcap may increase levels of drugs metabolized by CYP1A2 enzymes.
In vitro evidence suggests that constituents of Baikal skullcap inhibit the activity of CYP1A2. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, Baikal skullcap might increase levels of drugs metabolized by CYP2C19 enzymes.
In vitro evidence suggest that wogonin, a constituent of Baikal skullcap, modestly inhibits the activity of CYP2C19 enzymes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, concomitant use of large amounts of Baikal skullcap might interfere with hormone replacement therapy, due to competition for estrogen receptors.
In vitro evidence suggests that Baikal skullcap has estrogenic activity.

Likelihood Possible Evidence D
Lithium

Theoretically, Baikal skullcap might reduce lithium excretion and increase serum levels of lithium.
Baikal skullcap is thought to have diuretic properties, which may reduce lithium excretion. The dose of lithium might need to be decreased.

Likelihood Possible Evidence D
Alcohol (Ethanol)

Theoretically, Baikal skullcap might potentiate the sedative effects of alcohol.
In vitro and animal research suggests that Baikal skullcap binds to GABA-A receptors and causes sedation. Theoretically, Baikal skullcap might potentiate the sedative effects of alcohol. Preliminary clinical research has not identified clinically relevant sedation after use of Baikal skullcap; however, a thorough evaluation of safety outcomes has not been conducted.

Likelihood Unlikely Evidence D
Cns Depressants

Theoretically, Baikal skullcap might cause additive therapeutic and adverse effects when used concomitantly with drugs with sedative properties.
In vitro and animal research suggests that Baikal skullcap binds to GABA-A receptors and causes sedation. Theoretically, Baikal skullcap might cause additive therapeutic and adverse effects when used concomitantly with drugs with sedative properties. Preliminary clinical research has not identified clinically relevant sedation after use of Baikal skullcap; however, a thorough evaluation of safety outcomes has not been conducted.

Likelihood Unlikely Evidence D
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Theoretically, Baikal skullcap might alter the levels and clinical effects of OATP substrates.
Some pharmacokinetic research shows that baicalin, a constituent of Baikal skullcap, can decrease plasma levels of rosuvastatin. The mechanism is thought to involve stimulation of the activity of the organic anion-transporting polypeptide 1B1 (OATP1B1), which transports rosuvastatin into the liver. This decreases plasma levels of the drug, but increases levels at the site of action in the liver. The degree to which rosuvastatin levels are affected depends on the OATP1B1 haplotype of the individual. Baikal skullcap might also affect other OATP1B1 substrates.

Likelihood Possible Evidence B
P-Glycoprotein Substrates

Theoretically, Baikal skullcap might increase levels of drugs transported by P-glycoprotein.
In vitro and animal research suggests that baicalein, oroxylin A, and wogonin, constituents of Baikal skullcap, can inhibit P-glycoprotein. This effect has not been reported in humans.

Likelihood Possible Evidence D
Chinese Skullcap root extract full monograph & interactions

Black Tea leaf extract46 drug types · 694 drugs

Ephedrine

Theoretically, concomitant use might increase the risk for simulant adverse effects.
Black tea contains caffeine. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death. Tell patients to avoid taking caffeine with ephedrine and other stimulants.

Likelihood Probable Evidence D
Adenosine (Adenocard)

Theoretically, black tea might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Black tea contains caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level. However, caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine. It is recommended that methylxanthines such as caffeine, as well as methylxanthine-containing products, be stopped 24 hours prior to pharmacological stress tests. However, methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Possible Evidence B
Anticoagulant/Antiplatelet Drugs

Theoretically, black tea may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Black tea contains caffeine. Caffeine is reported to have antiplatelet activity. Theoretically, the caffeine in black tea might increase the risk of bleeding when used concomitantly with antiplatelet drugs. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Beta-Adrenergic Agonists

Theoretically, concomitant use of large amounts of black tea might increase cardiac inotropic effects of beta-agonists.
Black tea contains caffeine. Caffeine can increase cardiac inotropic effects of beta-agonists.

Likelihood Probable Evidence D
Carbamazepine (Tegretol)

Theoretically, black tea might reduce the effects of carbamazepine and increase the risk for convulsion.
Black tea contains caffeine. Animal research suggests that caffeine can lower the anticonvulsant effects of carbamazepine and can induce seizures when taken in doses above 400 mg/kg. Human research has shown that taking caffeine 300 mg in three divided doses along with carbamazepine 200 mg reduces the bioavailability of carbamazepine by 32% and prolongs the plasma half-life of carbamazepine 2-fold in healthy individuals.

Likelihood Possible Evidence B
Cimetidine (Tagamet)

Theoretically, concomitant use might increase the effects and adverse effects of caffeine in black tea.
Black tea contains caffeine. Cimetidine can reduces caffeine clearance by 31% to 42%.

Likelihood Likely Evidence B
Clozapine (Clozaril)

Theoretically, black tea might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Concomitant administration of black tea and clozapine might theoretically cause acute exacerbation of psychotic symptoms due to the caffeine in black tea. Caffeine can increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg daily inhibit clozapine metabolism. Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Researchers speculate that caffeine might inhibit CYP1A2. However, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients be more sensitive to the interaction between clozapine and caffeine.

Likelihood Possible Evidence B
Contraceptive Drugs

Theoretically, concomitant use might increase the effects and adverse effects of caffeine found in black tea.
Black tea contains caffeine. Oral contraceptive drugs can decrease caffeine clearance by 40% to 65%.

Likelihood Probable Evidence B
Cytochrome P450 1A2 (Cyp1A2) Inhibitors

Theoretically, concomitant use might increase the levels and adverse effects of caffeine.
Black tea contains caffeine. Caffeine is metabolized by CYP1A2,. Theoretically, drugs that inhibit CYP1A2 may decrease the clearance rate of caffeine from black tea and increase caffeine levels.

Likelihood Possible Evidence D
Dipyridamole (Persantine)

Theoretically, black tea might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Black tea contains caffeine. Caffeine is a methylxanthine that may inhibit dipyridamole-induced vasodilation. It is recommended that methylxanthines such as caffeine, as well as methylxanthine-containing products such as black tea, be stopped 24 hours prior to pharmacological stress tests. Methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram might increase the risk of adverse effects from caffeine.
Black tea contains caffeine. In human research, disulfiram decreases the clearance and increases the half-life of caffeine.

Likelihood Probable Evidence B
Diuretic Drugs

Theoretically, using black tea with diuretic drugs might increase the risk of hypokalemia.
Black tea contains caffeine. Caffeine, especially in excessive amounts, can reduce potassium levels due to stimulation of the sodium-potassium pump. Diuretics can also cause lower potassium levels.

Likelihood Possible Evidence D
Estrogens

Theoretically, estrogens might increase the levels and adverse effects of caffeine.
Black tea contains caffeine. Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Ethosuximide (Zarontin)

Theoretically, black tea might reduce the effects of ethosuximide and increase the risk for convulsions.
Black tea contains caffeine. Animal research suggests that caffeine 92.4 mg/kg can decrease the anticonvulsant activity of ethosuximide. However, this effect has not been observed in humans.

Likelihood Possible Evidence D
Felbamate (Felbatol)

Theoretically, black tea might reduce the effects of felbamate and increase the risk for convulsions.
Black tea contains caffeine. Animal research suggests that a high dose of caffeine 161.7 mg/kg can decrease the anticonvulsant activity of felbamate. However, this effect has not been observed in humans.

Likelihood Possible Evidence D
Flutamide (Eulexin)

Theoretically, black tea might increase the levels and adverse effects of flutamide.
Black tea contains caffeine. In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide. Theoretically, concomitant use of caffeine and flutamide might increase serum concentrations of flutamide and increase the risk of adverse effects.

Likelihood Possible Evidence D
Fluvoxamine (Luvox)

Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.
Black tea contains caffeine. Fluvoxamine reduces caffeine metabolism.

Likelihood Probable Evidence B
Lithium

Theoretically, abrupt black tea withdrawal might increase the levels and adverse effects of lithium.
Black tea contains caffeine. Abrupt caffeine withdrawal can increase serum lithium levels. Two cases of lithium tremor that worsened with abrupt coffee withdrawal have been reported.

Likelihood Probable Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use might increase the risk of a hypertensive crisis.
Black tea contains caffeine. Caffeine has been shown to inhibit monoamine oxidase (MAO) A and B in laboratory studies. Concomitant intake of large amounts of caffeine with MAOIs might precipitate a hypertensive crisis. In a case report, a patient that consumed 10-12 cups of caffeinate coffee and took the MAOI tranylcypromine presented with severe hypertension. Hypertension was resolved after the patients switched to drinking decaffeinated coffee.

Likelihood Possible Evidence D
Nicotine

Theoretically, concomitant use might increase the risk of hypertension.
Black tea contains caffeine. Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly.

Likelihood Probable Evidence B
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Theoretically, black tea might reduce the absorption of organic anion-transporting polypeptide (OATP) substrates.
In vitro, black tea extract inhibits organic anion-transporting polypeptide (OATP)2B1. OATP2B1 is expressed in the small intestine and liver and is responsible for the uptake of drugs and other compounds. In an animal model, black tea extract was found to inhibit the absorption of rosuvastatin, a substrate of OATP2B1. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Pentobarbital (Nembutal)

Theoretically, black tea might decrease the effects of pentobarbital.
Black tea contains caffeine. Theoretically, caffeine might negate the hypnotic effects of pentobarbital.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

Theoretically, black tea might reduce the effects of phenobarbital and increase the risk for convulsions.
Black tea contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenobarbital. The exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Phenylpropanolamine

Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.
Black tea contains caffeine. Concomitant use of phenylpropanolamine and caffeine might cause an additive increase in blood pressure. Phenylpropanolamine also seems to increase caffeine serum levels.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Theoretically, black tea might reduce the effects of phenytoin and increase the risk for convulsions.
Black tea contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenytoin. The effect does not seem to be related to the seizure threshold-lowering effects of caffeine. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Black Tea leaf extract full monograph & all 46 interactions

Cutch Tree wood & bark extract4 drug types · 475 drugs

Antihypertensive Drugs

Theoretically, concomitant use with antihypertensive drugs might increase the risk of hypotension.
Catechu might lower blood pressure.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, black catechu may increase the levels and clinical effects of CYP1A2 substrates.
Animal research shows that black catechu can increase theophylline concentrations in the blood, possibly by inhibiting CYP1A2. Theophylline is a CYP1A2 substrate.

Likelihood Possible Evidence D
Immunosuppressants

Theoretically, catechu might interfere with immunosuppressant therapy.
Animal and in vitro studies suggest that catechu has immunomodulating effects.

Likelihood Possible Evidence D
Theophylline

Theoretically, black catechu may increase the levels and clinical effects of theophylline.
Animal research shows that black catechu can increase theophylline concentrations in the blood, possibly by inhibiting cytochrome P450 1A2.

Likelihood Possible Evidence D
Cutch Tree wood & bark extract full monograph & interactions

Coenzyme Q-103 drug types · 198 drugs

Alkylating Agents

Coenzyme Q10 has antioxidant effects. Theoretically, this may reduce the activity of chemotherapy drugs that generate free radicals.
Theoretically, antioxidants such as coenzyme Q10 might protect tumor cells from chemotherapeutic agents that work by inducing oxidative stress, such as alkylating agents (e.g., cyclophosphamide) and radiation therapy. The clinical importance of this interaction is unknown.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Coenzyme Q10 is chemically similar to menaquinone and might have vitamin K-like procoagulant effects, which could decrease the effects of warfarin.
Concomitant use of coenzyme Q10 and warfarin might reduce the anticoagulant effects of warfarin. Four cases of decreased warfarin efficacy thought to be due to coenzyme Q10 have been reported. However, there is some preliminary clinical research that suggests coenzyme Q10 might not significantly decrease the effects of warfarin in patients who have a stable INR.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, coenzyme Q10 might have additive effects with antihypertensive drugs.
Some clinical research shows that coenzyme Q10 can significantly lower blood pressure, although other studies have shown conflicting results.

Likelihood Possible Evidence B
Coenzyme Q-10 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

Zeaxanthin1 drug type · 86 drugs

Antidiabetes Drugs

Theoretically, taking zeaxanthin with antidiabetes drugs might increase the risk of hypoglycemia.
In an animal diabetic model, zeaxanthin has hypoglycemic effects. However, population research has found that increasing intake of dietary zeaxanthin plus lutein does not decrease the risk of developing type 2 diabetes.

Likelihood Possible Evidence D
Zeaxanthin full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Healthy Cholesterol Formula, from the product label.

GNC Preventive Nutrition

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Phone Number
1-888-462-2548
Pharmacist Counseling Corner

Healthy Cholesterol Formula by GNC Preventive Nutrition: Common Questions

Does Healthy Cholesterol Formula by GNC Preventive Nutrition interact with any medications?
Yes. Based on its ingredients, Healthy Cholesterol Formula has a known interaction with 1,279 medications, including 15 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Healthy Cholesterol Formula contains 9 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 this while pregnant?
Calcium and lutein are likely safe in pregnancy at normal amounts, but zeaxanthin safety data are limited. Coenzyme Q10 has insufficient data. The biggest concern is Chinese skullcap and cutch tree extract — not enough safety information exists, so the facts advise against them in pregnancy. Talk to your doctor or pharmacist before starting.
Is this safe while breastfeeding?
Calcium and lutein are generally okay at recommended amounts. Black tea caffeine does pass into milk, so keep intake moderate. Coenzyme Q10 safety while breastfeeding hasn't been well studied. Chinese skullcap and cutch tree extract should be avoided — the data advise against them while nursing.
What does zeaxanthin do in this product?
Zeaxanthin is a yellow pigment that concentrates in the eye and has possibly effective evidence for age-related macular degeneration (AMD), the age-related eye disease. For other uses like cognitive decline and asthma, the evidence we hold is insufficient to rate.
Does black tea really have caffeine in this formula?
Yes — black tea leaf extract contains caffeine. That's why it interacts with stimulants, blood thinners, antithyroid drugs, and several psychiatric medications. If you're caffeine-sensitive or taking any of those drug types, this formula may not be right for you.
What are the common side effects?
Calcium can cause belching, constipation, or stomach upset. Coenzyme Q10 may cause mild digestive issues like nausea or diarrhea, usually in doses above 100 mg daily. Black tea's caffeine can trigger jitteriness, insomnia, nervousness, and nausea. Chinese skullcap may cause abdominal pain, nausea, or diarrhea. Most people tolerate these amounts fine.
Why can't this product be checked for all ingredients?
We hold no interaction data for betaine or the CardioAid Phytosterols blend — those ingredients haven't been checked through our monograph system. The other ingredients we've screened. If you want to know whether those specific ones interact with your medications, ask your pharmacist to look them up.

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.

Healthy Cholesterol Formula label
Go deeper

The Full Monographs Behind Healthy Cholesterol Formula’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

Black Tea

Interacts with 694 drugs

Black tea is a popular caffeinated drink made from the fully oxidized leaves of the Camellia sinensis plant, and it contains caffeine and antioxidant plant compounds. Moderate tea drinking i...

Read the full Black Tea monograph → Herb & supplement monograph

Zeaxanthin

Interacts with 86 drugs

Zeaxanthin is a carotenoid pigment that, along with lutein, concentrates in the macula of the eye and may help support long-term eye health. The strongest evidence relates to slowing progres...

Read the full Zeaxanthin monograph → Herb & supplement monograph

Lutein

Lutein is a plant-based antioxidant pigment that concentrates in the eye, and the best evidence suggests it (often combined with zeaxanthin) may help slow progression of age-related macular...

Read the full Lutein monograph → Herb & supplement monograph

Coenzyme Q10

Interacts with 198 drugs

CoQ10 is a vitamin-like substance your body makes naturally that helps cells produce energy and acts as an antioxidant. It is generally well tolerated and is most studied for heart condition...

Read the full Coenzyme Q10 monograph → Herb & supplement monograph

Baikal Skullcap

Interacts with 946 drugs

Baikal skullcap is a traditional Chinese herb (Huang Qin) used for inflammation, allergies, and infections, with active compounds like baicalin and baicalein studied mostly in the lab. Human...

Read the full Baikal Skullcap monograph → Herb & supplement monograph

Catechu

Interacts with 475 drugs

Catechu is an astringent extract made from the heartwood of the Acacia (Senegalia) catechu tree, used traditionally for mouth sores, sore throat, diarrhea, and minor skin problems. Strong hu...

Read the full Catechu monograph →
Sources

Sources & How We Checked

Healthy Cholesterol Formula'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 301 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.

Zeaxanthin 4 references
  1. Montonen J, Knekt P, Jarvinen R, Reunanen A. Dietary antioxidant intake and risk of type 2 diabetes. Diabetes Care 2004;27:362-6. PubMed
  2. Leermakers ET, Darweesh SK, Baena CP, et al. The effects of lutein on cardiometabolic health across the life course: a systematic review and meta-analysis. Am J Clin Nutr 2016;103(2):481-94. PubMed
  3. Kou L, Du M, Zhang C, Dai Z, Li X, Zhang B. The Hypoglycemic, Hypolipidemic, and Anti-Diabetic Nephritic Activities of Zeaxanthin in Diet-Streptozotocin-Induced Diabetic Sprague Dawley Rats. Appl Biochem Biotechnol 2017;182(3):944-955. PubMed
  4. Xu X, Zhao X, Berde Y, Low YL, Kuchan MJ. Milk and Plasma Lutein and Zeaxanthin Concentrations in Chinese Breast-Feeding Mother-Infant Dyads With Healthy Maternal Fruit and Vegetable Intake. J Am Coll Nutr 2019;38(2):179-184. PubMed

See these in context on the Zeaxanthin monograph →

Calcium 62 references
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  4. Maton PN, Burton ME. Antacids revisited: a review of their clinical pharmacology and recommended therapeutic use. Drugs 1999;57:855-70.
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  48. 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
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See these in context on the Calcium monograph →

Lutein 2 references
  1. Brown L, Rimm EB, Seddon JM, et al. A prospective study of carotenoid intake and risk of cataract extraction in US men. Am J Clin Nutr 1999;70:517-24. PubMed
  2. Chasan-Taber L, Willett WC, Seddon JM, et al. A prospective study of carotenoid and vitamin A intakes and risk of cataract extraction in US women. Am J Clin Nutr 1999;70:509-16. PubMed

See these in context on the Lutein monograph →

Coenzyme Q10 40 references
  1. Kamikawa T, Kobayashi A, Yamashita T, et al. Effects of coenzyme Q10 on exercise tolerance in chronic stable angina pectoris. Am J Cardiol 1985;56:247-51. PubMed
  2. Langsjoen P, Willis R, Folkers K. Treatment of essential hypertension with coenzyme Q10. Mol Aspects Med 1994;S265-72. PubMed
  3. Spigset O. Reduced effect of warfarin caused by ubidecarenone. Lancet 1994;334:1372-3. PubMed
  4. Singh RB, Niaz MA, Rastogi SS, et al. Effect of hydrosoluble coenzyme Q10 on blood pressures and insulin resistance in hypertensive patients with coronary artery disease. J Hum Hypertens 1999;13:203-8. PubMed
  5. Portakal O, Ozkaya O, Erden Inal M, et al. Coenzyme Q10 concentrations and antioxidant status in tissues of breast cancer patients. Clin Biochem 2000;33:279-84. PubMed
  6. Lund EL, Quistorff B, Spang-Thomsen M, Kristjansen PE. Effect of radiation therapy on small-cell lung cancer is reduced by ubiquinone intake. Folia Microbiol (Praha) 1998;43:505-6. PubMed
  7. Langsjoen PH, Langsjoen PH, Folkers K. Long-term efficacy and safety of coenzyme Q10 therapy for idiopathic dilated cardiomyopathy. Am J Cardiol 1990;65:521-3. PubMed
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See these in context on the Coenzyme Q10 monograph →

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Baikal Skullcap 34 references
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Catechu 9 references
  1. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
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See these in context on the Catechu monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

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.

© 2021 Therapeutic Research Center, LLC

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