Interactions on record — worth a quick check against your medications. Based on 2 of 4 ingredients. Check your meds →
Dietary supplement

Primadophilus Intensive Ingredients & Drug Interactions

by Nature's Way

Primadophilus Intensive label
See full label image
Powder 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 Primadophilus Intensive 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

Primadophilus Intensive is a dietary supplement by Nature's Way with 4 active ingredients. Its ingredients are commonly taken for constipation, diarrhea, high cholesterol.Based on those ingredients, 2,046 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Dietary Fiber, 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 Primadophilus Intensive by Nature's Way

Ask about any prescription or over-the-counter medication and we check it for interactions with Primadophilus Intensive by Nature's Way — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Primadophilus Intensive 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 Sep 3, 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 4 of its 4 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Primadophilus Intensive is a powder with 3 active ingredients. Vitamin C is an antioxidant and immune-supporting nutrient.

NutraFlora scFOS is a prebiotic (food for beneficial bacteria). The proprietary probiotic blend contains live beneficial bacteria strains — the exact species and counts aren't detailed on the label here.

The powder also contains potato starch and silica as inactive ingredients.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: digestive distress and flora replenishment.
  • We looked for evidence on: Constipation, Diarrhea, Dysbiosis, Gastrointestinal flora imbalance, Irritable bowel syndrome, Inflammatory bowel disease.
  • The strongest evidence on file: Black Psyllium is rated "Effective" for Constipation (Natural Medicines).
  • Also on file: Black Psyllium is rated "Insufficient Reliable Evidence To Rate" for Diarrhea.

Vitamin C is effective for preventing vitamin C deficiency. It's rated possibly effective for anemia of chronic disease, atrial fibrillation (irregular heart rhythm), cataracts, and exercise-induced respiratory infections.

We don't have effectiveness data in our records for the probiotic blend or prebiotic ingredient.

The evidence, ingredient by ingredient Black Psyllium 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 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 at normal dietary doses is well tolerated. At very high doses — above 2 grams daily — it can cause abdominal cramps, diarrhea, heartburn, nausea, and in rare cases kidney stones (especially if you're already prone to them).

Pregnancy and early lactation safety data on this product's ingredients show conflicting ratings — normal amounts from food and prenatal vitamins are fine, but avoid high-dose supplements without talking to your doctor first. The probiotic and prebiotic ingredients have no adverse effects listed in our data.

Side effects, ingredient by ingredient Black Psyllium 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?
  • 2 of the 2 matched ingredients can interact with medications — Black Psyllium, Vitamin C.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; cancer treatments; heart-rhythm medications; lithium.
  • For scale: 2,047 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 Primadophilus Intensive, check with your pharmacist or doctor if you take chemotherapy drugs (alkylating agents or antitumor antibiotics), estrogens (birth control or hormone therapy), blood thinners like warfarin, levothyroxine for your thyroid, antipsychotics, antiviral medications, or aluminum-containing antacids. These interactions are documented as Moderate severity.

Check your own medication Run your meds through the checker above

The bottom line

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

This product may work for you if you're looking to support vitamin C intake and your gut bacteria, but the vitamin C content means you'll want to check it against any medications you take — especially birth control, blood thinners, thyroid drugs, or chemotherapy. Talk with your own doctor or pharmacist before starting if you take any prescription medications or have a history of kidney stones.

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

Assessment coverage: 2 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jan 25, 2013.

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

At a glance

General information

Key facts about Primadophilus Intensive, straight from the product label.

Brand Nature's Way
Net contents 10 Powder Packet(s); 1.3 oz.
Market status On market
Date entered into DSLD Jan 25, 2013
DSLD ID 17991
Product type Other Combinations
Supplement form Powder
Dietary claims / uses Nutrient, 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 Primadophilus Intensive 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:
3.6 Gram(s)
Maximum serving Sizes:
3.6 Gram(s)
Servings per container
10
IngredientAmount% DV
Calories5 {Calories}--
Total Carbohydrates2 g1%
Dietary Fiber1 g2%
Vitamin C10 mg17%
NutraFlora scFOS500 mg--
Primadophilus(R) Intensive Proprietary Probiotic Blend990 mg--

Other ingredients: Potato Starch, 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.
Brand IP Statement(s)

NutraFlora(R) is a registered trademark of GTC Nutrition

PRIMADOPHILUS(R) INTENSIVE is specially formulated to provide maximum probiotic support, which can be beneficial for: {check} DIGESTIVE DISTRESS - to replenish the flora during and after episodes of digestive discomfort, irregularity, stress and antibiotic use* {check} IMMUNITY - to promote healthy immune function* {check} CLEANSING - to fortify the flora following an internal detox and cleansing program {check} TRAVELER'S AID - to fortify the flora before & during trips

TRUE POTENCY(TM) 100 Billion CFU

TRUE POTENCY(TM) Primadophilus(R) Intensive has a guaranteed potency of at least 100 billion CFU through to the expiration date stamped on this box. Most other probiotic brands claim their potency as of time of manufacture.

PRIMADOPHILUS(R) INTENSIVE helps replenish and fortify the intestinal tract with a high potency of healthy probiotics. Each serving delivers: {check} OVER 100 BILLION active probiotic cultures {check} TOTAL INTESTINAL SUPPORT with Lactobacillus (acidophilus & rhamnosus) for the small intestine and Bifidobacterium (breve, longum & bifidum) for the large intestine (colon)

2007

Seals/Symbols

ENHANCED WITH (symbol)(TM) NutraFlora(R)

{Nature's Way}(R)

FDA Statement of Identity

DIETARY SUPPLEMENT

General Statements

10-DAY PROGRAM FOR HEALTHY RESULTS

(3.6 GRAMS / 0.13 OZ EACH)

May contain a minimal residual amount of dairy or soy.

RESTORE YOUR INTESTINAL FLORA

- Optimal food source for probiotics and intestinal flora - Promotes healthy probiotic growth and colonization in the intestinal tract* - Superior to other FOS forms

10-DAY PROGRAM

MAXIMUM DIGESTIVE SUPPORT {check} Clinical Probiotic Dose {check} scFOS Prebiotic Action {check} Rapid Replenishment Formula for Intestinal Flora

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.

*This statement has not been evaluated by the Food & Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Storage

To maintain maximum potency, store packets in the refrigerator.

Suggested/Recommended/Usage/Directions

RECOMMENDATION: For best results, take 1 packet (3.6 g) daily for 10 consecutive days, preferably after a meal when the stomach is less acidic. Mix into yogurt, applesauce or other chilled soft foods, or stir briskly into beverages such as water, juice or milk (dairy, rice, soy, etc.) and consume immediately.

Precautions

Keep out of reach of children.

Formula

{check} PREBIOTIC ACTION with NutraFlora(R) scFOS (short-chain fructooligosaccharides)

General

R/0

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

See for yourself

Primadophilus Intensive by Nature's Way label

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

Primadophilus Intensive 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 Primadophilus Intensive by Nature's Way

These are the 4 active ingredients this product is made of. Select any to open its full monograph.

Serving size3.6 Gram(s) Dosage formPowder Servings per container10 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.

Dietary Fiber

Interacts with
2,025 drugs
1 g per serving

Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. I...

Dietary Fiber monograph & interactions

Vitamin C

Interacts with
207 drugs
10 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

NutraFlora scFOS

500 mg per serving

Primadophilus(R) Intensive Proprietary Probiotic Blend

990 mg per serving Form: Bifidobacterium bifidum-132, Bifidobacterium breve-129, Bifidobacterium longum-135, Lactobacillus acidophilus-122, Lactobacillus rhamnosus-111

Other (inactive) ingredients: Potato Starch, Silica. These complete the product’s ingredient list but are not active constituents.

Interaction report

Primadophilus Intensive by Nature's Way Drug Interactions

Want to check YOUR meds against Primadophilus Intensive?

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
2,046Drugs
124 Moderate 1,922 Minor

Ingredients driving the most interactions

Dietary Fiber 2,025
Vitamin C 207

Individual Drug Interactions

The ingredients in Primadophilus Intensive interact with 2,046 drugs. Click any drug to see the details.

2 of the 4 ingredients in Primadophilus Intensive interact with drugs. Each result below shows which ingredient is responsible. Dietary Fiber Vitamin C

Each ingredient & the kinds of drugs it affects

For each ingredient in Primadophilus Intensive 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.

Dietary Fiber7 drug types · 2,025 drugs

Carbamazepine (Tegretol)

Theoretically, black psyllium might reduce the effects of carbamazepine and increase the risk for convulsions.
Theoretically, black psyllium might reduce carbamazepine absorption. A preliminary study using blond psyllium reported decreased carbamazepine bioavailability due to binding of the drug to psyllium, as well as reduction of available fluid in the gut for dissolution of the drug. This interaction may also occur with black psyllium.

Likelihood Probable Evidence D
Lithium

Theoretically, taking black psyllium at the same time as lithium might reduce lithium absorption.
The fiber in black psyllium might reduce lithium absorption and plasma levels. Some case reports describe a reduction in plasma lithium levels with concomitant administration of blond psyllium. This was reversed when psyllium was stopped. This interaction may also occur with black psyllium.

Likelihood Probable Evidence D
Metformin (Glucophage)

Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Animal research shows that concurrent consumption of blond psyllium with metformin slows and increases the absorption of metformin. This interaction may also occur with black psyllium. To avoid changes in absorption, take psyllium 30-60 minutes after metformin.

Likelihood Possible Evidence D
Olanzapine (Zyprexa)

Theoretically, taking black psyllium at the same time as olanzapine might reduce olanzapine absorption.
The fiber in black psyllium might decrease the absorption of olanzapine. A single case report describes a reduction in the effectiveness of olanzapine when it was concomitantly administered with an unspecified type of psyllium 3 grams orally twice daily. This effect was reversed when psyllium was stopped.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Theoretically, taking black psyllium at the same time as digoxin might reduce digoxin absorption and decrease digoxin levels.
Psyllium might bind digoxin in the gut. However, some clinical evidence suggests that psyllium does not impact digoxin absorption.

Likelihood Unlikely Evidence B
Ethinyl Estradiol

Theoretically, taking black psyllium at the same time as ethinyl estradiol might alter levels of estradiol.
Concurrent use of blond psyllium with ethinyl estradiol results in a slight increase in the extent of ethinyl estradiol absorption and a slower rate of absorption. This is unlikely to be clinically significant.

Likelihood Unlikely Evidence D
Oral Drugs

Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Psyllium seems to have variable effects on drug absorption. To avoid changes in absorption, take psyllium 30-60 minutes after oral medications. Animal research shows that blond psyllium delays and increases the absorption of metformin and ethinyl estradiol. Case reports and animal research suggest that blond psyllium might reduce absorption of lithium, digoxin, olanzapine, and carbamazepine. Finally, some pharmacokinetic studies show that psyllium does not affect the absorption of levothyroxine or warfarin. Although many of these studies evaluated blond psyllium, the fiber content in black psyllium may have similar effects.

Likelihood Possible Evidence B
Dietary Fiber 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
The maker

Brand information

Manufacturer and brand details for Primadophilus Intensive, from the product label.

Nature's Way

See all Nature's Way products
Name
Nature's Way Products, Inc.
City
Springville
State
UT
ZipCode
84663
Phone Number
1-800-962-8873
Web Address
www.naturesway.com
Pharmacist Counseling Corner

Primadophilus Intensive by Nature's Way: Common Questions

Does Primadophilus Intensive by Nature's Way interact with any medications?
Yes. Based on its ingredients, Primadophilus Intensive has a known interaction with 2,046 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Primadophilus Intensive contains 4 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take this if I'm on birth control?
The vitamin C in this product may increase blood levels of estrogen-containing birth control by as much as 55% in some cases. You'll want to check with your pharmacist or doctor about whether that's a concern with your specific pill before starting.
Is this safe during pregnancy?
The safety data shows mixed ratings for vitamin C in pregnancy — normal amounts from food and prenatal vitamins are considered fine, but high-dose supplements aren't advised unless your doctor directs it. Talk with your own doctor before taking this product if you're pregnant or planning to be.
What exactly are the probiotics in this?
The label calls it a 'Primadophilus Intensive Proprietary Probiotic Blend,' but the specific bacterial strains and their amounts aren't listed on the product facts we have. You may want to check the package insert or contact the manufacturer for that detail.
Does this actually help with digestion or bloating?
We have no effectiveness data in our records for the probiotic or prebiotic ingredients in this product. Many people take probiotics for digestive support, but the evidence backing specific strains varies widely.
What side effects might I notice?
Vitamin C at normal doses is well tolerated. At higher doses (above 2 grams daily), some people experience abdominal cramps, diarrhea, heartburn, or nausea. The probiotic and prebiotic ingredients have no adverse effects listed in our data.
I'm on warfarin for my blood clot — is this okay?
High-dose vitamin C can reduce how well warfarin works by affecting its absorption. You need to check with your doctor or pharmacist before adding this product to be sure it won't interfere with your blood thinning.

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.

Primadophilus Intensive label
Go deeper

The Full Monographs Behind Primadophilus Intensive’s Ingredients

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

Herb & supplement monograph

Black Psyllium

Interacts with 2,025 drugs

Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. It is best known and most studied for rel...

Read the full Black Psyllium monograph → 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

Primadophilus Intensive'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 69 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.

Black Psyllium 18 references
  1. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  3. Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
  4. Etman M. Effect of a bulk forming laxative on the bioavailablility of carbamazepine in man. Drug Dev Ind Pharm 1995;21:1901-6.
  5. Perlman BB. Interaction between lithium salts and ispaghula husk. Lancet 1990;335:416.
  6. Vaswani SK, Hamilton RG, Valentine MD, Adkinson NF. Psyllium laxative-induced anaphylaxis, asthma, and rhinitis. Allergy 1996;51:266-8. PubMed
  7. Lantner RR, Espiritu BR, Zumerchik P, Tobin MC. Anaphylaxis following ingestion of a psyllium-containing cereal. JAMA 1990;264:2534-6. DOI
  8. Kaplan MJ. Anaphylactic reaction to "Heartwise." N Engl J Med 1990;323:1072-3. DOI
  9. Nordstrom M, Melander A, Robertsson E, Steen B. Influence of wheat bran and of a bulk-forming ispaghula cathartic on the bioavailability of digoxin in geriatric in-patients. Drug Nutr Interact 1987;5:67-9..
  10. Robinson DS, Benjamin DM, McCormack JJ. Interaction of warfarin and nonsystemic gastrointestinal drugs. Clin Pharmacol Ther 1971;12:491-5. PubMed
  11. Garcia JJ, Fernandez N, Diez MJ, et al. Influence of two dietary fibers in the oral bioavailability and other pharmacokinetic parameters of ethinyloestradiol. Contraception 2000;62:253-7. PubMed
  12. Fernandez N, Lopez C, Díez R, et al. Drug interactions with the dietary fiber Plantago ovata husk. Expert Opin Drug Metab Toxicol 2012;8(11):1377-86.
  13. Semen plantaginis in: WHO Monographs on Selected Medicinal Plants, volume 1. World Health Organization, Geneva, 1999. Available at http://apps.who.int/medicinedocs/en/d/Js2200e/. Accessed November 26, 1026.
  14. Code of Federal Regulations, Title 21 (21CFR 101.17). Food labeling warning, notice, and safe handling statements. Available at www.ecfr.gov/cgi-bin/text-idx?SID=20f647d3b74161501f46564b915b4048&mc=true&node=se21.2.101_117&rgn=div8. Accessed December 3, 2
  15. Code of Federal Regulations, Title 21 (21CFR 201.319). Specific labeling requirements - water-soluble gums, hydrophilic gums, and hydrophilic mucilloids. Available at www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=201.319. Accessed Dece
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See these in context on the Black Psyllium monograph →

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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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