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Dietary supplement

Focus Factor Macular Health Ingredients & Drug Interactions

by Focus Factor

Focus Factor Macular Health label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Focus Factor Macular Health 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: Moderate

Focus Factor Macular Health is a dietary supplement by Focus Factor with 7 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 1,060 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Grape Seed Extract, Vitamin E, Vitamin C. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Focus Factor Macular Health by Focus Factor

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HelloPharmacist Scorecard of Focus Factor Macular Health by Focus Factor

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

From our pharmacy team — supplement deep dive

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

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 7 of its 7 active ingredients.
  • “Folate” is listed as a grouped ingredient — the label gives one combined amount (400 mcg DFE) without saying how much of each component you get.

Focus Factor Macular Health contains 7 active ingredients. Folic acid and vitamin B12 support red blood cell formation and nervous system function.

Vitamins C and E are antioxidants that protect cells from damage. Zeaxanthin and lutein are carotenoids (plant pigments) that concentrate in the eye, particularly the macula, the part responsible for sharp vision.

Grape seed extract provides polyphenols, compounds with antioxidant properties. The product also contains inactive ingredients like microcrystalline cellulose, gelatin capsule, and other fillers.

Does it work?

Moderate 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
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: promotes healthy vision and macular retinal health.
  • We looked for evidence on: Age-related macular degeneration (AMD), Cataracts, Asthenopia (eye strain), blue light protection, retinal health, visual acuity.
  • The strongest evidence on file: Lutein is rated "Possibly Effective" for Age-related macular degeneration (AMD) (Natural Medicines).
  • Also on file: Lutein is rated "Possibly Effective" for Cataracts.
  • Also on file: Vitamin C is rated "Possibly Effective" for Cataracts.

Lutein is possibly effective for age-related macular degeneration (AMD) and cataracts. Zeaxanthin is possibly effective for AMD as well.

Folic acid is effective for folate deficiency and likely effective for preventing neural tube birth defects and reducing methotrexate toxicity; it's possibly effective for depression and cognitive problems. Vitamin C is effective for vitamin C deficiency and possibly effective for cataracts and exercise-related respiratory infections.

Vitamin E is effective for vitamin E deficiency and the rare condition ataxia with vitamin E deficiency (AVED); it's possibly effective for Alzheimer's disease. Vitamin B12 is effective for B12 deficiency and the rare condition Imerslund-Grasbeck disease.

Grape seed extract is possibly effective for chronic venous insufficiency but possibly ineffective for allergies and weight loss. For zeaxanthin and lutein with regard to cognitive decline and Alzheimer's disease, the evidence isn't established in our data.

The evidence, ingredient by ingredient Vitamin C Vitamin E Folic Acid Vitamin B12 Grape Zeaxanthin Lutein

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.

Folic acid, vitamin C, vitamin E, vitamin B12, grape seed extract, zeaxanthin, and lutein are generally well tolerated at standard doses. Folic acid is recommended during pregnancy at standard prenatal doses and considered safe while breastfeeding.

Vitamin B12 is needed in pregnancy and is safe at recommended amounts, and important during breastfeeding. Lutein is generally safe from food and typical supplement doses.

However, vitamin C in high doses above 2 grams daily can cause stomach upset, headache, kidney stones (especially in those prone to them), and other side effects. Vitamin E at high doses long-term may raise bleeding risk.

Grape seed extract is fine from food, but concentrated supplements should be avoided in pregnancy. Folic acid at very high doses (15 mg daily or more) can cause confusion, sleep problems, and irritability.

At high doses, folic acid can also worsen nerve damage in people with untreated vitamin B12 deficiency.

Side effects, ingredient by ingredient Vitamin C Vitamin E Folic Acid Vitamin B12 Grape Zeaxanthin Lutein

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 6 of the 7 matched ingredients can interact with medications — Grape, Vitamin B12, Vitamin E, Vitamin C, Folic Acid, among others.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; cancer treatments; diabetes medications.
  • For scale: 1,061 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 this product with your pharmacist if you take seizure medications like phenobarbital, primidone, or phenytoin; cancer drugs like capecitabine, methotrexate, or 5-fluorouracil; blood thinners or antiplatelet drugs like warfarin; estrogen-based birth control or hormone therapy; chemotherapy or immunosuppressants like cyclosporine; or diabetes medications. The folic acid, vitamins C and E, and grape seed extract all carry documented Moderate interactions with one or more of these drug types.

Check your own medication Run your meds through the checker above

The bottom line

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

This product may help support eye health and macular function, especially for those with AMD or at risk for it. If you take seizure medications, blood thinners, chemotherapy drugs, methotrexate, or diabetes medications, talk to your pharmacist before starting—several ingredients carry documented interactions.

Pregnant or breastfeeding? Check with your doctor, especially about folic acid and vitamin C at higher doses.

Your pharmacist can review your specific medicines against this product.

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

Assessment coverage: 7 of 7 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jan 23, 2025.

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

At a glance

General information

Key facts about Focus Factor Macular Health, straight from the product label.

Brand Focus Factor
Barcode (UPC) 811909034191
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Jan 23, 2025
DSLD ID 321668
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
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 Focus Factor Macular Health by Focus Factor, 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:
2 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
30
UPC/BARCODE
811909034191
IngredientAmount% DV
Folic Acid240 mcg--
Vitamin C250 mg278%
Vitamin E120 mg800%
Folate400 mcg DFE100%
Vitamin B1220 mcg833%
Grape Seed Extract50 mg--
Zeaxanthin2 mg--
Lutein10 mg--

Other ingredients: White Rice Flour, Microcrystalline Cellulose, Gelatin, Titanium Dioxide, Silicon Dioxide, Calcium Stearate

Tap any ingredient to jump to its full detail below.

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

As we get older, it is essential to take care of our eyes. Like other parts of your body, your eyes need proper nutrition to perform at their best.

For over 20 years, millions of people have trusted FOCUSfactor for their brain health products. FOCUSfactor has expanded the brand featuring a complete range of eye care products.

Synergy A consumer healthcare company

Formula

Our FOCUSfactor Macular Health Formula promotes healthy vision, macular & retinal health and supports the eye's ability to filter blue light with specific nutrients like lutein and zeaxanthin (in the clinically tested 5:1 ratio as Lutemax 2020).

Lutemax 2020 Lutein and Zeaxanthin Clinically Tested Ingredient

Formulation

Promotes healthy vision Helps maintain macular & retinal health Supports the eye's ability to filter blue light

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Suggested Use: As a dietary supplement, take 2 capsules once daily with food.

Brand IP Statement(s)

Lutemax 2020 is a trademark of OmniActive Health Technologies Ltd.

Precautions

Keep out of the reach of children.

This product is not a substitute for any medication. If you are pregnant, nursing, or suffer from a medical condition, consult a physician before taking this product.

Do not purchase if seal is missing or broken.

Storage

Store at 15-25 Degrees C (59-77 Degrees F). Protect from heat, light, and moisture.

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.

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

See for yourself

Focus Factor Macular Health by Focus Factor label

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

Focus Factor Macular Health 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 Focus Factor Macular Health by Focus Factor

These are the 7 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule 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.

Vitamin C

Interacts with
207 drugs
250 mg per serving Form: Ascorbic Acid

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...

Vitamin C monograph & interactions

Vitamin E

Interacts with
764 drugs
120 mg per serving Form: D-Alpha-Tocopheryl Succinate

Vitamin E is an essential fat-soluble vitamin and antioxidant that most people get in adequate amounts from a normal diet. Supplements can help correc...

Vitamin E monograph & interactions

Folate

400 mcg DFE per serving

Vitamin B12

Interacts with
20 drugs
20 mcg per serving Form: Methylcobalamin

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

Vitamin B12 monograph & interactions

Grape Seed Extract

Interacts with
910 drugs
50 mg per serving

Grapes and grape products like grape seed extract contain antioxidant compounds such as resveratrol and proanthocyanidins that may support heart and b...

Grape Seed Extract monograph & interactions

Zeaxanthin

Interacts with
86 drugs
2 mg per serving Form: Lutemax 2020

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 stron...

Zeaxanthin monograph & interactions

Lutein

No known
interactions
10 mg per serving Form: Lutemax 2020

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

Lutein monograph & interactions

Other (inactive) ingredients: White Rice Flour, Microcrystalline Cellulose, Gelatin, Titanium Dioxide, Silicon Dioxide, Calcium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Focus Factor Macular Health by Focus Factor Drug Interactions

Want to check YOUR meds against Focus Factor Macular Health?

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
1,060Drugs
1,028 Moderate 32 Minor

Ingredients driving the most interactions

Grape Seed Extract 910
Vitamin E 764
Vitamin C 207
Zeaxanthin 86
Folic Acid 40

Individual Drug Interactions

The ingredients in Focus Factor Macular Health interact with 1,060 drugs. Click any drug to see the details.

6 of the 7 ingredients in Focus Factor Macular Health interact with drugs. Each result below shows which ingredient is responsible. Grape Seed Extract Vitamin E Vitamin C Zeaxanthin Folic Acid Vitamin B12

Each ingredient & the kinds of drugs it affects

For each ingredient in Focus Factor Macular Health 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.

Grape Seed Extract9 drug types · 910 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, grape extracts may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
In vitro evidence suggests that grape extracts might decrease platelet aggregation.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

Ingesting grape juice with cyclosporine can reduce cyclosporine absorption.
A small pharmacokinetic study in healthy young adults shows that intake of purple grape juice 200 mL along with cyclosporine can decrease the absorption of cyclosporine by up to 30% when compared with water. Separate doses of grape juice and cyclosporine by at least 2 hours to avoid this interaction.

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

Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
A small pharmacokinetic study in healthy adults shows that ingestion of 200 mL of grape juice decreases phenacetin plasma levels. This is thought to be due to induction of CYP1A2.

Likelihood Possible Evidence B
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, grape seed extract may increase the levels of CYP2D6 substrates.
In vitro evidence suggests that grape seed extract might inhibit CYP2D6 enzymes. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2E1 (Cyp2E1) Substrates

Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
In vitro and animal research suggests that grape seed proanthocyanidin extract inhibits CYP2E1 enzymes. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
In vitro evidence suggests that grape seed extract might inhibit CYP3A4 enzymes. However, evidence from animal research shows that grape seed extract may induce CYP3A4 in the liver. So far, these interactions have not been reported in humans.

Likelihood Possible Evidence D
Midazolam (Versed)

Theoretically, long-term intake of grape seed extract might decrease the effects of midazolam.
Animal research shows that subchronic ingestions of grape seed extract can increase the elimination of intravenous midazolam by increasing hepatic CYP3A4 activity. Single doses of grape seed extract do not appear to affect midazolam elimination.

Likelihood Possible Evidence D
Phenacetin

Grape juice might decrease phenacetin absorption.
A small pharmacokinetic study in healthy adults shows that ingestion of 200 mL of grape juice decreases phenacetin plasma levels. This is thought to be due to induction of cytochrome P450 1A2 (CYP1A2).

Likelihood Possible Evidence B
Cytochrome P450 2C9 (Cyp2C9) Substrates

It is unclear if grape juice or grape seed extract inhibits CYP2C9; research is conflicting.
In vitro evidence shows that grape seed extract or grape juice might inhibit CYP2C9 enzymes. However, a small pharmacokinetic study in healthy adults shows that drinking 8 ounces of grape juice once does not affect the clearance of flurbiprofen, a probe-drug for CYP2C9 metabolism. The effects of continued grape juice consumption are unclear.

Likelihood Unlikely Evidence D
Grape Seed Extract full monograph & interactions

Vitamin E8 drug types · 764 drugs

Alkylating Agents

Theoretically, antioxidant effects of vitamin E might reduce the effectiveness of alkylating agents.
There's concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. However, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that might interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin E have on chemotherapy. Advise patients to consult their oncologist before using vitamin E supplements, especially in high doses.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Concomitant use of vitamin E and anticoagulant or antiplatelet agents might increase the risk of bleeding.
Vitamin E seems to inhibit of platelet aggregation and antagonize the effects of vitamin K-dependent clotting factors. These effects appear to be dose-dependent, and are probably only likely to be clinically significant with doses of at least 800 units daily. Mixed tocopherols, such as those found in food, might have a greater antiplatelet effect than alpha-tocopherol. RRR alpha-tocopherol (natural vitamin E) 1000 IU daily antagonizes vitamin K-dependent clotting factors. Advise patients to avoid high doses of vitamin E, especially in people with low vitamin K intake or other risk factors for bleeding.

Likelihood Possible Evidence B
Antitumor Antibiotics

Theoretically, antioxidant effects of vitamin E might reduce the effectiveness of antitumor antibiotics.
There's concern that antioxidants could reduce the activity of antitumor antibiotic drugs such as doxorubicin, which generate free radicals. However, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that might interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin E have on chemotherapy involving antitumor antibiotics. Advise patients to consult their oncologist before using vitamin E supplements, especially in high doses.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

A specific form of vitamin E might increase absorption and levels of cyclosporine.
There is some evidence that one specific formulation of vitamin E (D-alpha-tocopheryl-polyethylene glycol-1000 succinate, TPGS, tocophersolan, Liqui-E) might increase absorption of cyclosporine. This vitamin E formulation forms micelles which seems to increase absorption of cyclosporine by 40% to 72% in some patients. However, this interaction is unlikely to occur with the usual forms of vitamin E.

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

Theoretically, vitamin E might induce metabolism of CYP3A4, possibly reducing the levels CYP3A4 substrates.
Vitamin E appears to bind with the nuclear receptor, pregnane X receptor (PXR), which results in increased expression of CYP3A4. Although the clinical significance of this is not known, use caution when considering concomitant use of vitamin E and other drugs affected by these enzymes.

Likelihood Possible Evidence D
Selumetinib (Koselugo)

Taking selumetinib with vitamin E can result in a total daily dose of vitamin E that exceeds safe limits and therefore might increase the risk of bleeding.
Selumetinib contains 48-54 IU vitamin E per capsule. The increased risk of bleeding with vitamin E appears to be dose-dependent. Be cautious when using selumetinib in combination with supplemental vitamin E, especially in patients at higher risk of bleed, such as those with chronic conditions and those taking antiplatelet drugs.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Using vitamin E with warfarin might increase the risk of bleeding.
Due to interference with production of vitamin K-dependent clotting factors, use of more than 400 IU of vitamin E daily with warfarin might increase prothrombin time (PT), INR, and the risk of bleeding,. At a dose of 1000 IU per day, vitamin E can antagonize vitamin K-dependent clotting factors even in people not taking warfarin. Limited clinical evidence suggests that doses up to 1200 IU daily may be used safely by patients taking warfarin, but this may not be applicable in all patient populations.

Likelihood Possible Evidence B
Niacin

Vitamin E might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises high-density lipoprotein (HDL) cholesterol levels in people with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50%. Vitamin E alone combined with a statin does not seem to decrease HDL levels. It is not known whether the adverse effect on HDL is due to one of the other antioxidants or to the combination. It also is not known whether it will occur in other patient populations.

Likelihood Possible Evidence A
Vitamin E full monograph & interactions

Vitamin C13 drug types · 207 drugs

Alkylating Agents

Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Aluminum

Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.

Likelihood Probable Evidence B
Antitumor Antibiotics

Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Estrogens

Vitamin C might increase blood levels of estrogens.
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products. It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall. When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements. Monitor these patients for estrogen-related side effects.

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

Theoretically, vitamin C might decrease levels of fluphenazine.
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started. The mechanism is not known, and there is no further data to confirm this interaction.

Likelihood Possible Evidence D
Indinavir (Crixivan)

Vitamin C can modestly reduce indinavir levels.
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Vitamin C can increase levothyroxine absorption.
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH.

Likelihood Probable Evidence B
Warfarin (Coumadin)

High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

High-dose vitamin C might slightly prolong the clearance of acetaminophen.
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases. This effect is not likely to be clinically significant.

Likelihood Probable Evidence B
Aspirin

Acidification of the urine by vitamin C might increase aspirin levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Niacin

Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease. It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.

Likelihood Possible Evidence A
Salsalate (Disalcid)

Acidification of the urine by vitamin C might increase salsalate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Vitamin C 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

Folic Acid7 drug types · 40 drugs

5-Fluorouracil

Theoretically, high doses of folic acid might increase the toxicity of 5-fluorouracil.
Increases in gastrointestinal side effects of 5-fluorouracil, such as stomatitis and diarrhea, have been described in two clinical studies when leucovorin, a form of folic acid, was administered with 5-fluorouracil.

Likelihood Possible Evidence D
Capecitabine (Xeloda)

Use of high-dose folic acid might contribute to capecitabine toxicity.
Clinical research suggests that higher serum folate levels are associated with an increased risk for moderate or severe toxicity during capecitabine-based treatment for colorectal cancer. Additionally, in one case report, taking folic acid 15 mg daily might have contributed to increased toxicity, including severe diarrhea, vomiting, edema, hand-foot syndrome, and eventually death, in a patient prescribed capecitabine.

Likelihood Possible Evidence D
Methotrexate (Trexall, Others)

Folic acid might reduce the efficacy of methotrexate as a cancer treatment when given concurrently.
Methotrexate exerts its cytotoxic effects by preventing conversion of folic acid to the active form needed by cells. There is some evidence that folic acid supplements reduce the efficacy of methotrexate in the treatment of acute lymphoblastic leukemia, and theoretically they could reduce its efficacy in the treatment of other cancers. Advise cancer patients to consult their oncologist before using folic acid supplements. In patients treated with long-term, low-dose methotrexate for rheumatoid arthritis (RA) or psoriasis, folic acid supplements can reduce the incidence of side effects, without reducing efficacy.

Likelihood Probable Evidence B
Phenobarbital (Luminal)

Folic acid might have antagonistic effects on phenobarbital and increase the risk for seizures.
Folic acid can have direct convulsant activity in some people, reversing the effects of phenobarbital and worsening seizure control. Monitor closely for increased seizure activity.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Folic acid might reduce serum levels of phenytoin in some patients.
Folic acid may be a cofactor in phenytoin metabolism. Folic acid, in doses of 1 mg daily or more, can reduce serum levels of phenytoin in some patients. Increases in seizure frequency have been reported. If folic acid supplements are added to established phenytoin therapy, monitor serum phenytoin levels closely. If phenytoin and folic acid are started at the same time and continued together, adverse changes in phenytoin pharmacokinetics are avoided. Note that phenytoin also reduces serum folate levels.

Likelihood Probable Evidence B
Primidone (Mysoline)

Folic acid might have antagonistic effects on primidone and increase the risk for seizures.
Folic acid can have direct convulsant activity in some people, reversing the effects of primidone and worsening seizure control. Monitor closely for increased seizure activity. Note that primidone also reduces serum folate levels.

Likelihood Probable Evidence B
Pyrimethamine (Daraprim)

Folic acid might antagonize the effects of pyrimethamine.
Folic acid can antagonize the antiparasitic effects of pyrimethamine against toxoplasmosis and Pneumocystis carinii pneumonia. Folic acid doesn't antagonize the effects of pyrimethamine in the treatment of malaria, because malarial parasites cannot use exogenous folic acid. Use folinic acid as an alternative to folic acid when indicated.

Likelihood Probable Evidence D
Folic Acid full monograph & interactions

Vitamin B121 drug type · 20 drugs

Metformin (Glucophage)

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

Likelihood Possible Evidence A
Vitamin B12 full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Focus Factor Macular Health, from the product label.

Focus Factor

See all Focus Factor products
Name
Synergy CHC Corp.
Street Address
865 Spring Street
City
Westbrook
State
ME
ZipCode
04092
Pharmacist Counseling Corner

Focus Factor Macular Health by Focus Factor: Common Questions

Does Focus Factor Macular Health by Focus Factor interact with any medications?
Yes. Based on its ingredients, Focus Factor Macular Health has a known interaction with 1,060 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Focus Factor Macular Health contains 7 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is this safe to take if I'm pregnant?
Folic acid is recommended during pregnancy at standard prenatal doses and is considered safe—it actually helps prevent birth defects. Vitamin B12 is needed in pregnancy and is safe at recommended amounts. However, there isn't enough safety data on the higher supplement doses of vitamin C and vitamin E in pregnancy, and concentrated grape seed extract should be avoided. Talk with your doctor or pharmacist about whether this product is right for your pregnancy specifically.
Can I take this while breastfeeding?
Folic acid and vitamin B12 are considered safe at recommended doses while breastfeeding. Normal dietary amounts of lutein are fine. However, there isn't enough data on high-dose vitamin C or E supplements, or concentrated grape seed extract, while breastfeeding. Check with your doctor or pharmacist about what's appropriate for your situation.
What does this product actually do?
The lutein and zeaxanthin are included to support your macula—the part of your eye that gives you sharp, clear vision—and may help prevent or slow age-related macular degeneration. The B vitamins, vitamin C, and vitamin E provide additional antioxidant support. The grape seed extract adds more antioxidant compounds. Together, they're meant to protect eye and overall cell health.
Does it really work for my eyes?
Lutein and zeaxanthin are possibly effective for age-related macular degeneration and cataracts based on available evidence. That said, no supplement replaces a healthy diet, regular eye exams, or prescribed eye medications. If you have vision problems or AMD, your eye doctor is the best person to advise whether this product fits your care plan.
What are the side effects?
At standard doses, this product is generally well tolerated. The most common potential side effects are mild—stomach upset, headache, or dry mouth from the grape seed extract. At very high doses of vitamin C (above 2 grams daily), you could get diarrhea or kidney stones if you're prone to them. Folic acid at high doses can cause confusion and sleep problems. If you notice anything unusual after starting, let your pharmacist know.
Can I take this with my other supplements or vitamins?
Check with your pharmacist. If you're taking other multivitamins or supplements containing folic acid, vitamin C, vitamin E, lutein, zeaxanthin, or grape seed extract, you could get too much of these ingredients. Your pharmacist can review everything you're taking to make sure there's no overlap or interaction.

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

Not sure if Focus Factor Macular Health is safe with your meds?

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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.

Focus Factor Macular Health label
Go deeper

The Full Monographs Behind Focus Factor Macular Health’s Ingredients

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

Herb & supplement monograph

Vitamin C

Interacts with 207 drugs

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for immune function, collagen, and acts as an...

Read the full Vitamin C monograph → Herb & supplement monograph

Vitamin E

Interacts with 764 drugs

Vitamin E is an essential fat-soluble vitamin and antioxidant that most people get in adequate amounts from a normal diet. Supplements can help correct a true deficiency, but high-dose vitam...

Read the full Vitamin E monograph → Herb & supplement monograph

Folic Acid

Interacts with 40 drugs

Folic acid is the man-made form of vitamin B9 and is one of the most well-studied supplements, especially for preventing serious birth defects when taken before and during early pregnancy. I...

Read the full Folic Acid monograph → Herb & supplement monograph

Vitamin B12

Interacts with 20 drugs

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

Read the full Vitamin B12 monograph → Herb & supplement monograph

Grape

Interacts with 910 drugs

Grapes and grape products like grape seed extract contain antioxidant compounds such as resveratrol and proanthocyanidins that may support heart and blood vessel health. While the food is he...

Read the full Grape 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 →
Sources

Sources & How We Checked

Focus Factor Macular Health'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 241 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.

Folic Acid 56 references
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  32. Haberg, S. E., London, S. J., Stigum, H., Nafstad, P., and Nystad, W. Folic acid supplements in pregnancy and early childhood respiratory health. Arch Dis.Child 2009;94(3):180-184. PubMed
  33. Whitrow, M. J., Moore, V. M., Rumbold, A. R., and Davies, M. J. Effect of supplemental folic acid in pregnancy on childhood asthma: a prospective birth cohort study. Am J Epidemiol. 12-15-2009;170(12):1486-1493. PubMed
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  38. Taneja S, Strand TA, Kumar T, et al. Folic acid and vitamin B-12 supplementation and common infections in 6-30-mo-old children in India: a randomized placebo-controlled trial. Am J Clin Nutr 2013;98(3):731-7. PubMed
  39. van Wijngaarden JP, Swart KM, Enneman AW, et al. Effect of daily vitamin B-12 and folic acid supplementation on fracture incidence in elderly individuals with an elevated plasma homocysteine concentration: B-PROOF, a randomized controlled trial. Am J Clin
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  41. Crider KS, Cordero AM, Qi YP, Mulinare J, Dowling NF, Berry RJ. Prenatal folic acid and risk of asthma in children: a systematic review and meta-analysis. Am J Clin Nutr. 2013;98(5):1272-81. PubMed
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  43. Qin X, Cui Y, Shen L, Sun N, Zhang Y, Li J, Xu X, Wang B, Xu X, Huo Y, Wang X. Folic acid supplementation and cancer risk: a meta-analysis of randomized controlled trials. Int J Cancer. 2013 1;133(5):1033-41. PubMed
  44. Tio M, Andrici J, Cox MR, Eslick GD. Folate intake and the risk of prostate cancer: a systematic review and meta-analysis. Prostate Cancer Prostatic Dis. 2014;17(3):213-9. PubMed
  45. Tomaszewski JJ, Richman EL, Sadetsky N, O'Keefe DS, Carroll PR, Davies BJ, Chan JM. Impact of folate intake on prostate cancer recurrence following definitive therapy: data from CaPSURE. J Urol. 2014;191(4):971-6. PubMed
  46. Valera-Gran D, García de la Hera M, Navarrete-Muñoz EM, Fernandez-Somoano A, Tardón A, Julvez J, Forns J, Lertxundi N, Ibarluzea JM, Murcia M, Rebagliato M, Vioque J; Infancia y Medio Ambiente (INMA) Project. Folic acid supplements during pregnancy and ch
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  49. Vollset SE, Clarke R, Lewington S, Ebbing M, Halsey J, Lonn E, Armitage J, Manson JE, Hankey GJ, Spence JD, Galan P, Bønaa KH, Jamison R, Gaziano JM, Guarino P, Baron JA, Logan RF, Giovannucci EL, den Heijer M, Ueland PM, Bennett D, Collins R, Peto R; B-V
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See these in context on the Folic Acid monograph →

Vitamin C 51 references
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  36. Li, G., Li, L., Yu, C., and Chen, L. Effect of vitamins C and E supplementation on Helicobacter pylori eradication: a meta-analysis. Br.J Nutr 2011;106(11):1632-1637.
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  39. Yaich S, Chaabouni Y, Charfeddine K, et al. Secondary oxalosis due to excess vitamin C intake: a cause of graft loss in a renal transplant recipient. Saudi J Kidney Dis Transpl. 2014;25(1):113-6. PubMed
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  32. Berry AC, Nakshabendi R, Abidali H, et al. Adverse effects of grape seed extract supplement: A clinical case and long-term follow-up. J Diet Suppl. 2016;13(2):232-5. PubMed
  33. Martínez-Maqueda D, Zapatera B, Gallego-Narbón A, Vaquero MP, Saura-Calixto F, Pérez-Jiménez J. A 6-week supplementation with grape pomace to subjects at cardiometabolic risk ameliorates insulin sensitivity, without affecting other metabolic syndrome mark
  34. Moon SW, Shin YU, Cho H, Bae SH, Kim HK; and for the Mogen Study Group. Effect of grape seed proanthocyanidin extract on hard exudates in patients with non-proliferative diabetic retinopathy. Medicine (Baltimore) 2019;98(21):e15515. PubMed

See these in context on the Grape monograph →

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 →

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 →

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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