Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

Life Start 2 Ingredients & Drug Interactions

by Natren

Life Start 2 label
See full label image
Powder Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Life Start 2 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

Life Start 2 is a dietary supplement by Natren with 2 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, Bifidobacterium longum infantis NLS. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Life Start 2 by Natren

Ask about any prescription or over-the-counter medication and we check it for interactions with Life Start 2 by Natren — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
Prefer a human? Send your question to our licensed pharmacists — free, answered by email within 24 hours.

HelloPharmacist Scorecard of Life Start 2 by Natren

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

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 13, 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 1 of its 2 active ingredients.

Life Start 2 is a 2-ingredient powder combining vitamin C and a probiotic strain called Bifidobacterium longum infantis. The inactive ingredients are goat milk, brown rice milk concentrate, and organic brown rice syrup solids.

Vitamin C is an antioxidant vitamin that helps with immune function and tissue repair. Bifidobacterium longum infantis is a live beneficial bacteria intended to support digestive and immune health, especially in infants and young children.

Does it work?

Not established
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
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: infant digestive health and beneficial bacteria support.
  • We looked for evidence on: Antibiotic-associated diarrhea, Colic, Constipation, Diarrhea, Irritable bowel syndrome (IBS), infant microbiome — and 1 related terms.
  • The closest evidence on file: Bifidobacterium Longum is rated "Insufficient Reliable Evidence To Rate" for Antibiotic-associated diarrhea (Natural Medicines).
  • Also on file: Bifidobacterium Longum is rated "Insufficient Reliable Evidence To Rate" for Constipation, Diarrhea, Irritable bowel syndrome (IBS), Rotaviral diarrhea, and more.

Vitamin C is effective for treating vitamin C deficiency and possibly effective for anemia of chronic disease, atrial fibrillation, cataracts, and reducing respiratory infections after heavy exercise. For Bifidobacterium longum infantis, the evidence we hold does not establish effectiveness for the conditions listed in the data—these include age-related cognitive decline, hay fever, antibiotic-associated diarrhea, anxiety, asthma, and athletic performance.

That doesn't mean it has no benefit; it means reliable evidence for these specific uses isn't established in our data.

The evidence, ingredient by ingredient Vitamin C Bifidobacterium Longum

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Vitamin C is generally well tolerated at normal dietary doses. However, high doses above 2 grams daily can cause abdominal cramps, diarrhea, nausea, heartburn, and headache.

Kidney stones have been reported in people prone to them. Very high intravenous doses have rarely caused kidney problems and other serious effects.

Bifidobacterium longum infantis is generally well tolerated in healthy people, though it's not recommended for those who are seriously ill or have weakened immune systems. Rare side effects include abdominal discomfort, gas, constipation, and one reported case of dry cough.

There have been very rare reports of this bacteria entering the bloodstream in critically ill infants. For pregnancy, there isn't enough data to know whether this probiotic is safe; talk with your doctor or pharmacist before using it while pregnant or breastfeeding.

Side effects, ingredient by ingredient Vitamin C Bifidobacterium Longum

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?
  • 2 of the 2 matched ingredients can interact with medications — Vitamin C, Bifidobacterium Longum.
  • 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 Life Start 2, check with your doctor or pharmacist if you take blood thinners like warfarin, hormonal birth control or hormone replacement therapy, chemotherapy drugs, antipsychotics like fluphenazine, HIV medications like indinavir, antibiotics, or thyroid medication like levothyroxine. Antibiotics are particularly important—they can kill off the beneficial bacteria in this product, so you'd need to time them separately.

No interactions are documented for the Bifidobacterium beyond antibiotics; for vitamin C, the list above covers the main medication types affected.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glancePartially disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

Life Start 2 may be worth considering if you're looking for vitamin C and probiotic support, but it's not the right choice if you take blood thinners, hormonal birth control, hormone replacement therapy, antibiotics, or chemotherapy without checking with your doctor first. Don't take high-dose vitamin C supplements—this product is a powder you'll mix, so measure carefully and follow the label.

Talk with your doctor or pharmacist before starting it, especially if you're pregnant, breastfeeding, or have a weakened immune system.

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

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Mar 22, 2024.

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 Life Start 2, straight from the product label.

Brand Natren
Net contents 2.5 Ounce(s); 70.9 Gram(s)
Market status On market
Date entered into DSLD Mar 22, 2024
DSLD ID 307089
Product type Other Combinations
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Children (All), Infants/Baby (0 - 1 Year), Gluten 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 Life Start 2 by Natren, 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 Gram(s)
Maximum serving Sizes:
1 Gram(s)
Servings per container
70
IngredientAmount% DV
Vitamin C21 mg23%
Bifidobacterium longum infantis NLS0 NP--

Other ingredients: Goat Milk, Whole, Brown Rice Milk Concentrate, organic whole grain Brown Rice Syrup solids

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

Potency Guarantee: minimum of 2 billion cfu of live, active B. infantis beneficial probiotic bacteria NLS super strain per gram (approx. 1/2 level teaspoon) guaranteed through expiration date, if kept dry and refrigerated.

A gentle probiotic formula designed for a sensitive stomach Pharmaceutical grade quality probiotics Goat milk formula Viable super strain beneficial probiotic bacteria B. infantis NLS, to optimize digestion, support absorption and regularity

Probiotic powder for all ages

Suggested/Recommended/Usage/Directions

Suggested Use: take one gram (approx. 1/2 level teaspoon) daily mixed with 6 oz. unchilled, filtered (chlorine-free) water for about 2 minutes. For additional support you can increase the amount slowly until you are taking one gram (approx. 1/2 level teaspoon) five times per day or until you achieve desired results. For babies or toddlers you can use a portion of the formula or non-acidic juice to dissolve Life Start 2, then add mixture to remaining liquid and shake bottle to thoroughly mix. Take Life Start 2 preferably before meals and at least 2 hours apart from herbs, garlic and prescription drugs for optimal results. May be taken along with other Natren products.

Precautions

Take Life Start 2 preferably before meals and at least 2 hours apart from herbs, garlic and prescription drugs for optimal results.

Do not accept if seal is broken.

Formulation

The Trenev Process, a unique proprietary process, substantially increases the probiotic benefits by keeping the bacteria in their natural environment (supernatant) to ensure potency and efficacy, eliminating the need for additives.

Researched, formulated and manufactured by Natren Guaranteed 100% Potency through expiration date

Contains no preservatives or artificial colors and flavors. Natren does not use ingredients produced using biotechnology. Gluten free Soy free No GMO's No FOS

Made in USA

General Statements

For more information, please call for a complimentary brochure.

Healthy Friends

Storage

Do not freeze or expose to moisture, heat or direct sunlight. Keep refrigerated and dry to maintain potency guarantee.

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.

Brand IP Statement(s)

Natren The Probiotic Specialist Recognized Worldwide since 1982

Copyright 2021

FDA Statement of Identity

Probiotic Dietary Supplement

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

See for yourself

Life Start 2 by Natren label

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

Life Start 2 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 Life Start 2 by Natren

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Gram(s) Dosage formPowder Servings per container70 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
21 mg per serving

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

Bifidobacterium longum infantis NLS

Interacts with
182 drugs
0 NP per serving

Bifidobacterium longum is a 'friendly' bacterium found naturally in the human gut and used as a probiotic. It is generally well tolerated and is most...

Bifidobacterium longum infantis NLS monograph & interactions

Other (inactive) ingredients: Goat Milk, Whole, Brown Rice Milk Concentrate, Organic whole grain Brown Rice Syrup solids. These complete the product’s ingredient list but are not active constituents.

Interaction report

Life Start 2 by Natren Drug Interactions

Want to check YOUR meds against Life Start 2?

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
Bifidobacterium longum infantis NLS 182

Individual Drug Interactions

The ingredients in Life Start 2 interact with 386 drugs. Click any drug to see the details.

2 of the 2 ingredients in Life Start 2 interact with drugs. Each result below shows which ingredient is responsible. Vitamin C Bifidobacterium longum infantis NLS

Each ingredient & the kinds of drugs it affects

For each ingredient in Life Start 2 with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Vitamin 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

Bifidobacterium longum infantis NLS1 drug type · 182 drugs

Antibiotic Drugs

Theoretically, taking Bifidobacterium longum with antibiotic drugs might decrease the effectiveness of B. longum.
Since B. longum preparations usually contain live and active organisms, simultaneously taking antibiotics might kill a significant number of the organisms. Tell patients to separate administration of antibiotics and B. longum preparations by at least 2 hours.

Likelihood Probable Evidence D
Bifidobacterium longum infantis NLS full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Life Start 2, from the product label.

Natren

See all Natren products
Name
Natren Inc
City
Westlake Village
State
CA
ZipCode
91361
Phone Number
800-992-3323
Web Address
www.natren.com
Pharmacist Counseling Corner

Life Start 2 by Natren: Common Questions

Does Life Start 2 by Natren interact with any medications?
Yes. Based on its ingredients, Life Start 2 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?
Life Start 2 contains 2 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.
Will taking this with my antibiotic stop it from working?
No—but the antibiotic might kill off the probiotic bacteria in this product, making it pointless to take them together. Ask your pharmacist to help you time them at least a few hours apart so both can do their job.
Is this safe to give to my infant?
The data we hold has limited safety information for Bifidobacterium longum in infants, including a few rare reports of serious infections in very sick or premature babies. This is a decision to make with your child's pediatrician, especially if your baby has any underlying conditions or is on antibiotics.
Can I take this while pregnant?
The vitamin C in normal amounts from prenatal vitamins is fine, but avoid high-dose supplements unless your doctor tells you otherwise. The probiotic strain hasn't been studied enough in pregnancy for us to say whether it's safe; talk it over with your obstetrician before starting.
What does Bifidobacterium longum infantis do?
It's a live beneficial bacteria that's intended to support digestive and immune health, particularly in infants and young children. The evidence for specific health claims in our data isn't established, so it's unclear what it actually does for most conditions.
Can high doses of vitamin C cause side effects?
Yes. Doses above 2 grams daily can cause diarrhea, nausea, abdominal cramps, heartburn, and headache. Very high doses, especially by IV, have rarely caused kidney stones and serious kidney problems. Stick to the dose on the label.

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

Not sure if Life Start 2 is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.

Life Start 2 label
Go deeper

The Full Monographs Behind Life Start 2’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

Bifidobacterium Longum

Interacts with 182 drugs

Bifidobacterium longum is a 'friendly' bacterium found naturally in the human gut and used as a probiotic. It is generally well tolerated and is most studied for digestive issues, though evi...

Read the full Bifidobacterium Longum monograph →
Sources

Sources & How We Checked

Life Start 2'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 72 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
  28. Taylor EN, Stampfer MJ, Curhan GC. Dietary factors and the risk of incident kidney stones in men: new insights after 14 years of follow-up. J Am Soc Nephrol 2004;15:3225-32. PubMed
  29. Ward NC, Hodgson JM, Croft KD, et al. The combination of vitamin C and grape-seed polyphenols increases blood pressure: a randomized, double-blind, placebo-controlled trial. J Hypertens 2005;23:427-34.. PubMed
  30. Prasad KN. Rationale for using high-dose multiple dietary antioxidants as an adjunct to radiation therapy and chemotherapy. J Nutr 2004;134:3182S-3S. PubMed
  31. Conklin KA. Cancer chemotherapy and antioxidants. J Nutr 2004;134:3201S-3204S. PubMed
  32. Fairweather-Tait S, Hickson K, McGaw B, et al. Orange juice enhances aluminium absorption from antacid preparation. Eur J Clin Nutr. 1994;48(1):71-3.
  33. Gruenwald, J., Graubaum, H. J., Busch, R., and Bentley, C. Safety and tolerance of ester-C compared with regular ascorbic acid. Adv.Ther. 2006;23(1):171-178.
  34. Rahimi, R., Nikfar, S., Rezaie, A., and Abdollahi, M. A meta-analysis on the efficacy and safety of combined vitamin C and E supplementation in preeclamptic women. Hypertens.Pregnancy. 2009;28(4):417-434. PubMed
  35. Einerson, B., Nathorn, C., Kitiyakara, C., Sirada, M., and Thamlikitkul, V. The efficacy of ascorbic acid in suboptimal responsive anemic hemodialysis patients receiving erythropoietin: a meta-analysis. J Med.Assoc.Thai. 2011;94 Suppl 1:S134-S146.
  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.
  37. Chen X, Shen L, Gu X, et al. High-dose supplementation with vitamin C--induced pediatric urolithiasis: the first case report in a child and literature review. Urology. 2014;84(4):922-4. PubMed
  38. Sattar A, Willman JE, Kolluri R. Possible warfarin resistance due to interaction with ascorbic acid: case report and literature review. Am J Health Syst Pharm. 2013;70(9):782-6. PubMed
  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
  40. Jalloh MA, Gregory PJ, Hein D, et al. Dietary supplement interactions with antiretrovirals: a systematic review. Int J STD AIDS. 2017 Jan;28(1):4-15. PubMed
  41. Rumbold A, Ota E, Nagata C, Shahrook S, Crowther CA. Vitamin C supplementation in pregnancy. Cochrane Database Syst Rev. 2015;(9):CD004072. PubMed
  42. Seo MS, Kim JK, Shim JY. High-dose vitamin C promotes regression of multiple pulmonary metastases originating from hepatocellular carcinoma. Yonsei Med J. 2015;56(5):1449-52. PubMed
  43. Skelin M, Lucijanic T, Amidzic Klaric D, et al. Factors Affecting Gastrointestinal Absorption of Levothyroxine: A Review. Clin Ther. 2017 Feb;39(2):378-403. PubMed
  44. Jiang K, Tang K, Liu H, Xu H, Ye Z, Chen Z. Ascorbic acid supplements and kidney stones incidence among men and women: a systematic review and meta-analysis. Urol J. 2019;16(2):115-120.
  45. Thomas S, Patel D, Bittel B, et al. Effect of High-Dose Zinc and Ascorbic Acid Supplementation vs Usual Care on Symptom Length and Reduction Among Ambulatory Patients With SARS-CoV-2 Infection: The COVID A to Z Randomized Clinical Trial. JAMA Netw Open. 2 PubMed
  46. Giffen MA, McLemore JL. Hyperoxalosis Secondary to Intravenous Vitamin C Administration as a Non-Allopathic Treatment for Cancer. Acad Forensic Pathol 2019;9(1-2):118-126. PubMed
  47. Maike A, Sturgill D, Gallan A. Oxalate Nephropathy in a Renal Transplant Recipient After Receiving High Dose Ascorbic Acid. Am J Med Sci 2021. PubMed
  48. Shen ZY, Chen YR, Wang MC, Chang SS. High-dose vitamin C-induced acute oxalate nephropathy in a renal transplant recipient: a case report and literature review. Asian J Surg 2022. PubMed
  49. Yanase F, Spano S, Maeda A, et al. Mega-dose sodium ascorbate: a pilot, single-dose, physiological effect, double-blind, randomized, controlled trial. Crit Care 2023;27(1):371. PubMed
  50. Sharma Y, Sumanadasa S, Shahi R, et al. Efficacy and safety of vitamin C supplementation in the treatment of community-acquired pneumonia: a systematic review and meta-analysis with trial sequential analysis. Sci Rep 2024;14(1):11846. PubMed
  51. Pejcic AV, Petrovic NZ, Djordjic MD, Milosavljevic MN. Vitamin C Levels in Pregnant Women and the Efficacy of Vitamin C Supplements in Preventing Premature Rupture of Membranes: A Systematic Review and Meta-Analysis. Balkan Med J 2024;41(4):248-260. PubMed

See these in context on the Vitamin C monograph →

Bifidobacterium Longum 21 references
  1. Ha GY, Yang CH, Kim H, Chong Y. Case of sepsis caused by Bifidobacterium longum. J Clin Microbiol 1999;37:1227-8.
  2. Pierce A. The American Pharmaceutical Association Practical Guide to Natural Medicines. New York: The Stonesong Press, 1999:19.
  3. Xiao JZ, Takahashi S, Odamaki T, et al. Antibiotic susceptibility of bifidobacterial strains distributed in the Japanese market. Biosci Biotechnol Biochem. 2010;74(2):336-42. PubMed
  4. Rautava S, Kainonen E, Salminen S, Isolauri E. Maternal probiotic supplementation during pregnancy and breast-feeding reduces the risk of eczema in the infant. J Allergy Clin Immunol. 2012;130(6):1355-60. PubMed
  5. Pruccoli G, Silvestro E, Pace Napoleone C, Aidala E, Garazzino S, Scolfaro C. Are probiotics safe? Bifidobacterium bacteremia in a child with severe heart failure. Infez Med. 2019;27(2):175-178.
  6. Pellonperä O, Vahlberg T, Mokkala K, et al. Weight gain and body composition during pregnancy: a randomised pilot trial with probiotics and/or fish oil. Br J Nutr. 2020 Nov 4:1-11. PubMed
  7. Pellonperä O, Mokkala K, Houttu N, et al. Efficacy of fish oil and/or probiotic intervention on the incidence of gestational diabetes mellitus in an at-risk group of overweight and obese women: A randomized, placebo-controlled, double-blind clinical trial PubMed
  8. Shahriari A, Karimi E, Shahriari M, Aslani N, Khooshideh M, Arab A. The effect of probiotic supplementation on the risk of gestational diabetes mellitus among high-risk pregnant women: A parallel double-blind, randomized, placebo-controlled clinical trial PubMed
  9. Esaiassen E, Hjerde E, Cavanagh JP, Simonsen GS, Klingenberg C; Norwegian Study Group on Invasive Bifidobacterial Infections. Bifidobacterium bacteremia: Clinical characteristics and a genomic approach to assess pathogenicity. J Clin Microbiol. 2017;55(7) PubMed
  10. Enomoto T, Sowa M, Nishimori K, et al. Effects of bifidobacterial supplementation to pregnant women and infants in the prevention of allergy development in infants and on fecal microbiota. Allergol Int 2014;63(4):575-85. PubMed
  11. US Food and Drug Administration (FDA). Dear Healthcare Provider Letter: Warning Regarding Use of Probiotics in Preterm Infants. September 2023. Available at: https://www.fda.gov/media/172606/download?attachment. Accessed November 1, 2023.
  12. Pillai A, Tan J, Paquette V, Panczuk J. Does probiotic bacteremia in premature infants impact clinically relevant outcomes? A case report and updated review of literature. Clin Nutr ESPEN. 2020;39:255-259. PubMed
  13. Sabaté JM, Iglicki F. Effect of Bifidobacterium longum 35624 on disease severity and quality of life in patients with irritable bowel syndrome. World J Gastroenterol 2022;28(7):732-744.
  14. Malaguarnera M, Greco F, Barone G, Gargante MP, Malaguarnera M, Toscano MA. Bifidobacterium longum with fructo-oligosaccharide (FOS) treatment in minimal hepatic encephalopathy: a randomized, double-blind, placebo-controlled study. Dig Dis Sci 2007;52(11) PubMed
  15. Zbinden A, Zbinden R, Berger C, Arlettaz R. Case series of Bifidobacterium longum bacteremia in three preterm infants on probiotic therapy. Neonatology 2015;107(1):56-9.
  16. Tamaki H, Nakase H, Inoue S, et al. Efficacy of probiotic treatment with Bifidobacterium longum 536 for induction of remission in active ulcerative colitis: A randomized, double-blinded, placebo-controlled multicenter trial. Dig Endosc 2016;28(1):67-74.
  17. Bertelli C, Pillonel T, Torregrossa A, et al. Bifidobacterium longum bacteremia in preterm infants receiving probiotics. Clin Infect Dis 2015;60(6):924-7. PubMed
  18. Esaiassen E, Cavanagh P, Hjerde E, Simonsen GS, Støen R, Klingenberg C. Bifidobacterium longum subspecies infantis bacteremia in 3 extremely preterm infants receiving probiotics. Emerg Infect Dis 2016;22(9):1664-6.
  19. Tena D, Losa C, Medina MJ, Sáez-Nieto JA. Peritonitis caused by Bifidobacterium longum: case report and literature review. Anaerobe 2014;27:27-30. PubMed
  20. Sangkanjanavanich S, Pradubpongsa P, Mitthamsiri W, Sangasapaviliya A, Boonpiyathad T. Bifidobacterium infantis 35624 efficacy in patients with uncontrolled asthma: A randomized placebo-controlled trial. Ann Allergy Asthma Immunol 2022;129(6):790-792. PubMed
  21. Wilson HL, Ong CW. Bifidobacterium longum vertebrodiscitis in a patient with cirrhosis and prostate cancer. Anaerobe 2017;47:47-50. PubMed

See these in context on the Bifidobacterium Longum 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

Keep exploring
Supplement interaction checker › Check any supplement or product against your medications Drug–drug interactions › Check two or more of your medications against each other Browse medications A–Z › Every drug we've checked against herbs & supplements NDC & pricing lookup › Find a drug’s NDCs, packaging and costs Ask a pharmacist › Free, personal answer from our licensed team