Interactions on record — worth a quick check against your medications. Based on 1 of 3 ingredients. Check your meds →
Dietary supplement

Fortify Optima Immune Probiotic 50 Billion Ingredients & Drug Interactions

by Nature's Way

Fortify Optima Immune Probiotic 50 Billion label
See full label image
Capsule Category: Non-nutrient/non-botanical
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 Fortify Optima Immune Probiotic 50 Billion 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

Fortify Optima Immune Probiotic 50 Billion is a dietary supplement by Nature's Way with 3 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 386 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Vitamin C. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Fortify Optima Immune Probiotic 50 Billion by Nature's Way

Ask about any prescription or over-the-counter medication and we check it for interactions with Fortify Optima Immune Probiotic 50 Billion by Nature's Way — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Fortify Optima Immune Probiotic 50 Billion by Nature's Way

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

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 1 of its 8 active ingredients.
  • “Fortify Optima” is listed as a grouped ingredient — the label gives one combined amount (256 mg) without saying how much of each component you get.
  • “Lactobacilli HDS Probiotics” is listed as a grouped ingredient — the label doesn't break down how much of each component you get.
  • “Bifidobacteria HDS Probiotics” is listed as a grouped ingredient — the label doesn't break down how much of each component you get.

This product contains 8 ingredients, including vitamin C and live probiotic organisms. The active ingredients are vitamin C for immune support and antioxidant function, plus a blend of Lactobacilli and Bifidobacteria probiotics — the specific strains include L. acidophilus (La-14 and NCFM), L. gasseri (Lg-36), and several Bifidobacterium strains.

These are meant to support gut health and digestion. The rest of the formula is made up of inactive ingredients like the capsule shell, cellulose, magnesium stearate, and silica.

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: digestive support and immune health.
  • We looked for evidence on: Antibiotic-associated diarrhea, Diarrhea, Clostridioides difficile infection, Common cold, Constipation, Dyspepsia — and 4 related terms.
  • The strongest evidence on file: Lactobacillus Acidophilus is rated "Possibly Effective" for Antibiotic-associated diarrhea (Natural Medicines).
  • Also on file: Lactobacillus Acidophilus is rated "Possibly Effective" for Helicobacter pylori.
  • Also on file: Vitamin C is rated "Possibly Ineffective" for Helicobacter pylori.

Vitamin C is established as effective for treating vitamin C deficiency and is possibly effective for anemia, heart rhythm issues, cataracts, and respiratory infections from heavy exercise. L. acidophilus is possibly effective for irritable bowel syndrome, H. pylori infection, antibiotic-associated diarrhea, and bacterial vaginosis.

L. gasseri and the other probiotic strains in this formula don't have enough evidence in our data to rate how well they work for their intended uses — the evidence just isn't established yet.

The evidence, ingredient by ingredient Vitamin C

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 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Vitamin C is generally well tolerated at normal supplement doses, but very high doses can cause side effects like stomach cramps, heartburn, diarrhea, nausea, and kidney stones (especially in people prone to them). Side effects are more likely above 2 grams daily.

The Lactobacillus and Bifidobacterium strains are also generally well tolerated in healthy adults; rare gastrointestinal side effects like bloating, flatulence, and diarrhea can occur when taking probiotics together, but these are uncommon. Because these probiotics contain live organisms, there's a theoretical concern they could cause serious infection in people with compromised immune systems, though this is rare.

For pregnancy and breastfeeding, normal amounts of vitamin C from food and prenatal vitamins are fine, but avoid high-dose supplements unless your doctor says otherwise. We don't have safety data on file for the individual probiotic strains — talk with your doctor or pharmacist for personalized advice if you're pregnant or nursing.

Side effects, ingredient by ingredient Vitamin C

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?
  • 3 of the 3 matched ingredients can interact with medications — Lactobacillus Acidophilus, Vitamin C, Lactobacillus Gasseri.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; cancer treatments.
  • For scale: 386 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, check your exact medications against the list on this page if you take birth control or hormone replacement therapy (estrogens), chemotherapy drugs, warfarin or other blood thinners, levothyroxine (thyroid medication), the HIV drug indinavir, the antipsychotic fluphenazine, or any antibiotic. The antibiotic interaction is Moderate in severity — spacing out the doses helps, but confirm the timing with your pharmacist.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This probiotic-plus-vitamin-C formula might appeal to you if you're looking to support gut health and immunity, but you'll need to check it carefully against any medications you take — especially birth control, hormone therapy, antibiotics, blood thinners, thyroid medication, or chemotherapy. If you take antibiotics, space them several hours away from this supplement so the live probiotics don't get killed off.

Talk to your pharmacist before you start.

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

Assessment coverage: 4 of 8 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 24, 2020.

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

At a glance

General information

Key facts about Fortify Optima Immune Probiotic 50 Billion, straight from the product label.

Brand Nature's Way
Barcode (UPC) 033674107638
Net contents 30 Delayed-Release Veg. Capsule(s)
Market status On market
Date entered into DSLD Jun 24, 2020
DSLD ID 228024
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Fortify Optima Immune Probiotic 50 Billion by Nature's Way, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
UPC/BARCODE
033674107638
IngredientAmount% DV
Vitamin C60 mg67%
Fortify Optima256 mg--
Lactobacilli HDS Probiotics0 NP--
Bifidobacteria HDS Probiotics0 NP--
B. lactis Bi-070 NP--
B. lactis/bifidum HDS (Bb-02)0 NP--
B. lactis (Bl-04)0 NP--
B. infantis (Bi-26)0 NP--
L. acidophilus (La-14)0 NP--
L. gasseri (Lg-36)0 NP--
L. acidophilus (NCFM)0 NP--

Other ingredients: plant-derived Capsule, Cellulose, Magnesium Stearate, Silica

Tap any ingredient to jump to its full detail below.

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

50 billion active cultures, guaranteed!

50 Billion Live probiotic cultures per capsule 7 probiotic strains

Specifically formulated with a proprietary blend of probiotics, Fortify Optima is a powerful ally with BI-04 and BI-07 researched probiotic strains to support healthy immune function. Lactobacilli cultures to work in your small intestines Bifidobacteria cultures to support your colon Formulated with 7 probiotic strains + vitamin C Fortify Optima 50 billion CFU formula contains 7 probiotic strains designed to support gut diversity + vitamin C to support immune health. 100% unique human digestive strain probiotics

Formulation

Guaranteed to deliver 50 billion live probiotic cultures until the date of expiration without refrigeration to provide digestive support and promote immune health. Targeted delivery Each capsule is resistant to the harmful effects of stomach acid and distributes live cultures to the proper are of the small intense and colon, right where they needed most! One capsule, multiple benefits Taking Fortify Optima every day helps support: Healthy immune function Gut diversity Colon health

Guaranteed potency

Digestive support Colon health Immune health

Gluten and dairy free. No artificial colors.

Powerful probiotics for daily digestion support & immune health

Originated from human microflora Compatible with your digestive system

Not from plant, soil, animal, or dairy sources

Researched probiotic strains

Gluten-free Dairy-free No artificial flavors

Brand IP Statement(s)

2020 Distributed by Nature's Way Brands, LLC

BI-04 and BI-07 are trademarks of DuPont. In the USA, NCFM is a trademark of the North Carolina Agriculture Foundation, Inc. NCFM, BI-04, and BI-07, are used under license.

FDA Disclaimer Statement

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

General Statements

Since 1969

Potency of live cultures measured in Colony Forming Units (CFU).

FDA Statement of Identity

Probiotic Supplement

Suggested/Recommended/Usage/Directions

Recommendation: Take 1 capsule daily. May be taken at any time, with or without food.

Precautions

If you are pregnant, nursing, or taking any medications, consult a healthcare professional before use.

Keep out of reach of children.

Safety sealed in individual blister units. Do not use if individual blisters are open or torn.

Storage

May be refrigerated.

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

See for yourself

Fortify Optima Immune Probiotic 50 Billion by Nature's Way label

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

Fortify Optima Immune Probiotic 50 Billion 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 Fortify Optima Immune Probiotic 50 Billion by Nature's Way

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule 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
60 mg per serving Form: Potassium Ascorbate

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

Fortify Optima

256 mg per serving
  • › Lactobacilli HDS Probiotics
  • › Bifidobacteria HDS Probiotics

Other (inactive) ingredients: Plant-derived Capsule, Cellulose, Magnesium Stearate, Silica. These complete the product’s ingredient list but are not active constituents.

Interaction report

Fortify Optima Immune Probiotic 50 Billion by Nature's Way Drug Interactions

Want to check YOUR meds against Fortify Optima Immune Probiotic 50 Billion?

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
386Drugs
280 Moderate 106 Minor

Ingredients driving the most interactions

Vitamin C 207

Individual Drug Interactions

The ingredients in Fortify Optima Immune Probiotic 50 Billion interact with 386 drugs. Click any drug to see the details.

1 of the 3 ingredients in Fortify Optima Immune Probiotic 50 Billion interact with drugs. Each result below shows which ingredient is responsible. Vitamin C

Each ingredient & the kinds of drugs it affects

For each ingredient in Fortify Optima Immune Probiotic 50 Billion with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

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
The maker

Brand information

Manufacturer and brand details for Fortify Optima Immune Probiotic 50 Billion, from the product label.

Nature's Way

See all Nature's Way products
Name
Nature's Way Brands, LLC
City
Green Bay
State
WI
ZipCode
54311
Phone Number
1-800-962-8873
Web Address
fortifyprobiotics.com
Pharmacist Counseling Corner

Fortify Optima Immune Probiotic 50 Billion by Nature's Way: Common Questions

Does Fortify Optima Immune Probiotic 50 Billion by Nature's Way interact with any medications?
Yes. Based on its ingredients, Fortify Optima Immune Probiotic 50 Billion has a known interaction with 386 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Fortify Optima Immune Probiotic 50 Billion contains 3 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
What's the actual dose of vitamin C in this product, and will it cause side effects?
The facts don't specify how much vitamin C is in each dose of this product. Most side effects from vitamin C happen above 2 grams daily — at lower doses, it's generally well tolerated. If you want to know the exact amount in your bottle, check the label or ask us.
Does this help with IBS or digestion?
L. acidophilus in this product is possibly effective for irritable bowel syndrome, but the evidence isn't ironclad. The other probiotic strains don't have enough research data to rate how well they work. If you're hoping for help with a digestive issue, talk with your doctor or pharmacist about whether this is a good fit for you.
Can I take this while I'm on antibiotics?
Not at the same time. The live probiotics in this supplement (L. acidophilus and L. gasseri) can be killed by antibiotics, which defeats the purpose. Space them out several hours apart — ask your pharmacist or doctor for the exact timing that works best with your specific antibiotic.
Is it safe to take this if I'm pregnant or breastfeeding?
Vitamin C at normal amounts from food and prenatal vitamins is fine during pregnancy, but avoid high-dose supplements unless your doctor tells you to. We don't have specific safety data on the individual probiotic strains in this formula for pregnancy and breastfeeding — talk with your doctor or pharmacist for personalized advice.
Are there any fillers or 'junk' in here?
This product contains the probiotic blend and vitamin C plus inactive ingredients: the capsule shell, cellulose, magnesium stearate, and silica. These are standard excipients, not fillers in the sense of bulking agents with no function.
What if I take a supplement that isn't on your interaction list — does that mean it's safe?
Not necessarily. We only have data for vitamin C and two of the Lactobacillus strains; we couldn't check the other probiotic strains. The absence of documented interaction data isn't the same as proof there's no interaction. Use the checker on this page with your exact medications, and ask your pharmacist if anything isn't clear.

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.

Fortify Optima Immune Probiotic 50 Billion label
Go deeper

The Full Monographs Behind Fortify Optima Immune Probiotic 50 Billion’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 →
Sources

Sources & How We Checked

Fortify Optima Immune Probiotic 50 Billion'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 78 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.

Vitamin C 51 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Back DJ, Breckenridge AM, MacIver M, et al. Interaction of ethinyloestradiol with ascorbic acid in man. Br Med J (Clin Res Ed) 1981;282:1516.
  3. Morris JC, Beeley L, Ballantine N. Interaction of ethinyloestradiol with ascorbic acid in man [letter]. Br Med J (Clin Res Ed) 1981;283:503.
  4. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  5. Dwyer JH, Merz NB, Shirocre AM, et al. Progression of early atherosclerosis and intake of vitamin C and vitamin E from supplements and food. The Los Angeles Atherosclerosis Study. 41st Annual Conference on Cardiovascular Disease Epidemiology and Prevent
  6. Levine M, Rumsey SC, Daruwala R, et al. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415-23. PubMed
  7. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  8. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  9. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Press, 2000. Available at: http://www.nap.edu/books/0309069351/html/.
  10. Houston JB, Levy G. Drug biotransformation interactions in man VI: Acetaminophen and ascorbic acid. J Pharm Sci 1976;65:1218-21. PubMed
  11. Brown BG, Zhao XQ, Chait A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med 2001;345:1583-93. DOI
  12. Rosenthal G. Interaction of ascorbic acid and warfarin. JAMA 1971;215:1671. DOI
  13. Hume R, Johnstone JM, Weyers E. Interaction of ascorbic acid and warfarin. JAMA 1972;219:1479. DOI
  14. Smith EC, Skalski RJ, Johnson GC, Rossi GV. Interaction of ascorbic acid and warfarin. JAMA 1972;221:1166. DOI
  15. Traxer O, Huet B, Poindexter J, et al. Effect of ascorbic acid consumption on urinary stone risk factors. J Urol 2003;170:397-401.. PubMed
  16. Domingo JL, Gomez M, Llobet JM, Richart C. Effect of ascorbic acid on gastrointestinal aluminum absorption (letter). Lancet 1991;338:1467.
  17. Domingo JL, Gomez M, Llobet JM, Corbella J. Influence of some dietary constituents on aluminum absorption and retention in rats. Kidney Int 1991;39:598-601. PubMed
  18. Partridge NA, Regnier FE, White JL, Hem SL. Influence of dietary constituents on intestinal absorption of aluminum. Kidney Int 1989;35:1413-7. PubMed
  19. Mc Leod DC, Nahata MC. Inefficacy of ascorbic acid as a urinary acidifier (letter). N Engl J Med 1977;296:1413. DOI
  20. Hansten PD, Hayton WL. Effect of antacid and ascorbic acid on serum salicylate concentration. J Clin Pharmacol 1980;20:326-31. PubMed
  21. Dysken MW, Cumming RJ, Channon RA, Davis JM. Drug interaction between ascorbic acid and fluphenazine. JAMA 1979;241:2008. DOI
  22. Vihtamaki T, Parantainen J, Koivisto AM, et al. Oral ascorbic acid increases plasma oestradiol during postmenopausal hormone replacement therapy. Maturitas 2002;42:129-35. PubMed
  23. Slain D, Amsden JR, Khakoo RA, et al. Effect of high-dose vitamin C on the steady-state pharmacokinetics of the protease inhibitor indinavir in healthy volunteers. Pharmacotherapy 2005;25:165-70. PubMed
  24. Cheung MC, Zhao XQ, Chait A, et al. Antioxidant supplements block the response of HDL to simvastatin-niacin therapy in patients with coronary artery disease and low HDL. Arterioscler Thromb Vasc Biol 2001;21:1320-6. PubMed
  25. Feetam CL, Leach RH, Meynell MJ. Lack of a clinically important interaction between warfarin and ascorbic acid. Toxicol Appl Pharmacol 1975;31:544-7. PubMed
  26. Weintraub M, Griner PF. Warfarin and ascorbic acid: lack of evidence for a drug interaction. Toxicol Appl Pharmacol 1974;28:53-6. PubMed
  27. Lee DH, Folsom AR, Harnack L, et al. Does supplemental vitamin C increase cardiovascular disease risk in women with diabetes? Am J Clin Nutr 2004;80:1194-200. PubMed
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Lactobacillus Acidophilus 15 references
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  2. Begtrup LM, de Muckadell OB, Kjeldsen J, Christensen RD, Jarbøl DE. Long-term treatment with probiotics in primary care patients with irritable bowel syndrome--a randomised, double-blind, placebo controlled trial. Scand J Gastroenterol 2013;48(10):1127-35 PubMed
  3. Chatterjee S, Kar P, Das T, Ray S, Gangulyt S, Rajendiran C, Mitra M. Randomised placebo-controlled double blind multicentric trial on efficacy and safety of Lactobacillus acidophilus LA-5 and Bifidobacterium BB-12 for prevention of antibiotic-associated
  4. Shavakhi A, Tabesh E, Yaghoutkar A, Hashemi H, Tabesh F, Khodadoostan M,Minakari M, Shavakhi S, Gholamrezaei A. The effects of multistrain probiotic compound on bismuth-containing quadruple therapy for Helicobacter pylori infection: a randomized placebo-c
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  7. Kumar S, Kumar R, Rohilla L, Jacob N, Yadav J, Sachdeva N. A high potency multi-strain probiotic improves glycemic control in children with new-onset type 1 diabetes mellitus: A randomized, double-blind, and placebo-controlled pilot study. Pediatr Diabete
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See these in context on the Lactobacillus Acidophilus monograph →

Lactobacillus Gasseri 12 references
  1. Pierce A. The American Pharmaceutical Association Practical Guide to Natural Medicines. New York: The Stonesong Press, 1999:19.
  2. Ramachandran L, Dontaraju VS, Patel K. Lactobacillus-associated spontaneous bacterial peritonitis in a liver cirrhosis patient on probiotics. Cureus. 2020;12(12):e11896. PubMed
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See these in context on the Lactobacillus Gasseri monograph →

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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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