Interactions on record — worth a quick check against your medications. Based on 7 of 10 ingredients. Check your meds →
Dietary supplement

Challenge Ingredients & Drug Interactions

by Loomis Enzymes

Challenge label
See full label image
Powder Category: Botanical With Nutrients
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Challenge 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

Challenge is a dietary supplement by Loomis Enzymes with 10 active ingredients. Its ingredients are commonly taken for replacing fluids and electrolytes, preventing dehydration during exercise or illness, treating low blood sodium (under medical care).Based on those ingredients, 2,205 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Dietary Fiber, Guar Gum, Fennel. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Challenge by Loomis Enzymes

Ask about any prescription or over-the-counter medication and we check it for interactions with Challenge by Loomis Enzymes — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Challenge by Loomis Enzymes

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 12, 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 8 of its 8 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Challenge contains seven active ingredients: sodium, flaxseed, psyllium, fig, fennel, pumpkin, and guar gum. These are digestive aids and plant-based supplements meant to support bowel function and general digestive health.

The product contains no inactive ingredients (fillers or binders) listed.

Does it work?

Couldn't assess
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 assessable

We hold no graded evidence for this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: pH balancing system.
  • Our graded evidence for these ingredients doesn't cover that particular purpose.

The evidence for these ingredients is mixed and mostly modest. Flaxseed is possibly effective for high cholesterol, diabetes, and constipation.

Guar gum is possibly effective for high blood pressure, high cholesterol, irritable bowel syndrome, and constipation. Fig and pumpkin have insufficient reliable evidence to rate their effectiveness for the conditions listed in our data.

Sodium has limited uses—it's likely effective for cystic fibrosis and possibly effective for preventing amphotericin B kidney damage, but you would not take a supplement for sodium unless your doctor directed it. Fennel is possibly effective for period pain; the other uses in our data lack sufficient evidence.

We hold no effectiveness data for psyllium.

The evidence, ingredient by ingredient Sodium Black Psyllium Flaxseed Fig Fennel Pumpkin Guar Gum

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

These ingredients are generally well tolerated in food amounts. Sodium in excess is linked to high blood pressure and heart strain—normal dietary intake is fine, but avoid supplementing without medical advice.

Flaxseed commonly causes bloating, gas, and diarrhea, especially at higher doses; start small and drink plenty of water. Fig as food is safe; concentrated leaf products are less studied.

Fennel is well tolerated as food but should be avoided in medicinal amounts during pregnancy due to hormone-like effects and limited safety data. Pumpkin as food is safe; gastrointestinal upset (nausea, diarrhea, abdominal discomfort) is the main concern with concentrated supplements.

Guar gum must be taken with plenty of water to avoid throat or bowel blockage and commonly causes gas, bloating, and loose stools. Pregnancy and lactation safety data vary by ingredient; talk to your doctor or pharmacist before using during these periods.

Side effects, ingredient by ingredient Sodium Black Psyllium Flaxseed Fig Fennel Pumpkin Guar Gum

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?
  • 7 of the 7 matched ingredients can interact with medications — Black Psyllium, Fennel, Fig, Pumpkin, Guar Gum, among others.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; heart-rhythm medications; lithium.
  • For scale: 2,206 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 Challenge, check with your pharmacist if you take blood pressure medications (antihypertensives), blood thinners or antiplatelet drugs, diabetes medications or insulin, lithium, any birth control pill, corticosteroids, antibiotics (especially ciprofloxacin or penicillin), estrogen therapy or tamoxifen, or any oral medications in general—guar gum can reduce how quickly your body absorbs them. All of these interactions are Moderate except for digoxin, which is Minor.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Challenge is a multi-ingredient digestive aid with modest evidence behind most of its components. If you take any blood pressure medication, diabetes drug, blood thinner, lithium, or birth control pill, check your exact medications with the tool on this page before starting.

Start with a small dose to minimize bloating and gas, and drink plenty of water, especially if you're taking guar gum. Talk to your pharmacist about whether this product fits your health picture.

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

Assessment coverage: 7 of 8 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 23, 2025.

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

At a glance

General information

Key facts about Challenge, straight from the product label.

Brand Loomis Enzymes
Barcode (UPC) 697706041408
Net contents 8 Ounce(s); 226.8 Gram(s)
Market status On market
Date entered into DSLD Feb 23, 2025
DSLD ID 327424
Product type Botanical With Nutrients
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Challenge by Loomis Enzymes, 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:
9 Gram(s)
Maximum serving Sizes:
9 Gram(s)
Servings per container
25
UPC/BARCODE
697706041408
IngredientAmount% DV
Calories35 Calorie(s)--
Total Carbohydrates6 Gram(s)2%
Sugar1 Gram(s)--
Sodium10 mg1%
Total Fat1 Gram(s)1%
Dietary Fiber4 Gram(s)15%
Protein1 Gram(s)1%
Flaxseed1360 mg--
Psyllium1830 mg--
Fig2830 mg--
Fennel1800 mg--
Pumpkin980 mg--
Guar Gum200 mg--

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.
Formulation

pHBS pH Balancing System

FDA Disclaimer Statement

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

Precautions

Keep out of reach of children

Psyllium warning: May cause allergic reaction in people sensitive to inhaled or ingested psyllium.

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

Do not use if inner or outer seal is broken, torn, or missing.

Do not consume dry.

Storage

To ensure freshness and potency, keep bottle tightly closed and store in a cool, dry place. Product filled by weight not volume

FDA Statement of Identity

A Dietary Supplement

Suggested/Recommended/Usage/Directions

Directions for use: Take 9 g (- 1 rounded tablespoon) between meals, 2 times daily or as directed. Blend thoroughly in a full 8 oz. glass of water or juice to avoid swallowing difficulty. Do not consume dry.

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

See for yourself

Challenge by Loomis Enzymes label

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

Challenge 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 Challenge by Loomis Enzymes

These are the 10 active ingredients this product is made of. Select any to open its full monograph.

Serving size9 Gram(s) Dosage formPowder Servings per container25 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.

Sugar

1 Gram(s) per serving

Sodium

Interacts with
205 drugs
10 mg per serving

Sodium is an essential mineral and electrolyte your body needs to balance fluids, support nerves, and help muscles work. Most people in modern diets g...

Sodium monograph & interactions

Dietary Fiber

Interacts with
2,025 drugs
4 Gram(s) 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

Protein

1 Gram(s) per serving

Flaxseed

Interacts with
597 drugs
1360 mg per serving

Flaxseed is a nutritious food rich in fiber, omega-3 fats (ALA), and plant compounds called lignans. It is most reliably helpful for constipation and...

Flaxseed monograph & interactions

Psyllium

1830 mg per serving Form: Plantago ovata

Fig

Interacts with
410 drugs
2830 mg per serving Form: Ficus carica

Fig (Ficus carica) is a common fruit that has long been used as a gentle food remedy for constipation, and its leaves are used traditionally for blood...

Fig monograph & interactions

Fennel

Interacts with
740 drugs
1800 mg per serving Form: Foeniculum vulgare

Fennel is a Mediterranean herb widely used as a food and spice, and traditionally taken for digestive complaints, colic, and menstrual cramps. Some sm...

Fennel monograph & interactions

Pumpkin

Interacts with
1 drug
980 mg per serving Form: Cucurbita pepo

Pumpkin is a nutritious squash, and its seeds and seed oil are the parts most often used as supplements, mainly for urinary and prostate symptoms. The...

Pumpkin monograph & interactions

Guar Gum

Interacts with
2,025 drugs
200 mg per serving

Guar gum is a soluble, gel-forming fiber from the guar bean that may modestly help with cholesterol, blood sugar, and bowel regularity. It is generall...

Guar Gum monograph & interactions
Interaction report

Challenge by Loomis Enzymes Drug Interactions

Want to check YOUR meds against Challenge?

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
2,205Drugs
2,205 Moderate

Ingredients driving the most interactions

Dietary Fiber 2,025
Guar Gum 2,025
Fennel 740
Flaxseed 597
Fig 410

Individual Drug Interactions

The ingredients in Challenge interact with 2,205 drugs. Click any drug to see the details.

7 of the 10 ingredients in Challenge interact with drugs. Each result below shows which ingredient is responsible. Dietary Fiber Guar Gum Fennel Flaxseed Fig Sodium Pumpkin

Each ingredient & the kinds of drugs it affects

For each ingredient in Challenge 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

Guar Gum5 drug types · 2,025 drugs

Ethinyl Estradiol

Theoretically, guar gum might reduce the absorption of ethinyl estradiol, potentially decreasing its effectiveness.
Animal research shows that taking guar gum with ethinyl estradiol decreases ethinyl estradiol absorption. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Metformin (Glucophage)

Guar gum might reduce the absorption of metformin, potentially decreasing its effectiveness.
A small study in healthy volunteers shows that guar gum reduces the absorption rate of metformin.

Likelihood Probable Evidence B
Oral Drugs

Guar gum might reduce the absorption of some oral drugs, potentially decreasing their effectiveness.
Clinical research shows that guar gum reduces or slows absorption of medications such as penicillin and metformin. To avoid changes in absorption, take guar gum 30-60 minutes after oral medications.

Likelihood Possible Evidence B
Penicillin

Guar gum might reduce the absorption of penicillin, potentially decreasing its effectiveness.
A small clinical study in healthy volunteers shows that taking guar gum with penicillin results in decreased penicillin absorption and reduced penicillin levels.

Likelihood Probable Evidence B
Digoxin (Lanoxin)

Guar gum might slow digoxin absorption, but it does not seem to impact how much digoxin is absorbed overall.
Two small studies in healthy volunteers show no change in the overall extent of digoxin absorption, although early absorption was slowed, when taken with guar gum.

Likelihood Possible Evidence B
Guar Gum full monograph & interactions

Fennel6 drug types · 740 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, fennel might increase the risk of bleeding when used with antiplatelet or anticoagulant drugs.

Animal research suggests that fennel oil has antithrombotic and antiplatelet effects.

Likelihood Possible Evidence D
Ciprofloxacin (Cipro)

Theoretically, fennel might decrease the levels and clinical effects of ciprofloxacin.

Animal research shows that fennel reduces ciprofloxacin bioavailability by nearly 50%, possibly due to the metal cations such as calcium, iron, and magnesium contained in fennel. This study also found that fennel increased tissue distribution and slowed elimination of ciprofloxacin.

Likelihood Probable Evidence D
Contraceptive Drugs

Theoretically, taking large amounts of fennel might decrease the effects of contraceptive drugs due to competition for estrogen receptors.

Some constituents of fennel have estrogenic activity.

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

Theoretically, fennel might increase levels of drugs metabolized by CYP3A4.

In vitro research suggests that fennel inhibits CYP3A4 enzyme activity. This effect has not been reported in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, taking large amounts of fennel might interfere with hormone replacement therapy due to competition for estrogen receptors.

Some constituents of fennel have estrogenic activity.

Likelihood Possible Evidence D
Tamoxifen (Nolvadex)

Theoretically, taking large amounts of fennel might decrease the antiestrogenic effect of tamoxifen.

Some constituents of fennel have estrogenic activity, which may interfere with the antiestrogenic activity of tamoxifen.

Likelihood Possible Evidence D
Fennel full monograph & interactions

Flaxseed5 drug types · 597 drugs

Antibiotic Drugs

Theoretically, antibiotics might interfere with the metabolism of flaxseed constituents, which could potentially alter the effects of flaxseed.
Some potential benefits of flaxseed are thought to be due to its lignan content. Secoisolariciresinol diglucoside (SDG), a major lignan precursor, is found in high concentrations in flaxseed. SDG is converted by bacteria in the colon to the lignans enterolactone and enterodiol. Antibiotics alter the flora of the colon, which could theoretically alter the metabolism of flaxseed.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, using flaxseed in combination with anticoagulant or antiplatelet drugs might have additive effects and increase the risk of bleeding.
Some clinical evidence suggests that the oil contained in flaxseed can decrease platelet aggregation.

Likelihood Possible Evidence B
Antidiabetes Drugs

Theoretically, flaxseed might have additive effects when used with antidiabetes drugs and increase the risk for hypoglycemia.
Some clinical research suggests that flaxseed can lower blood glucose levels.

Likelihood Probable Evidence B
Antihypertensive Drugs

Theoretically, flaxseed might have additive effects when used with antihypertensive drugs and increase the risk of hypotension.
Clinical research shows that daily flaxseed consumption, especially for longer than 12 weeks, modestly reduces blood pressure.

Likelihood Possible Evidence D
Estrogens

Theoretically, taking flaxseed might decrease the effects of estrogens.
Flaxseed contains lignans with mild estrogenic and possible antiestrogenic effects. The lignans seem to compete with circulating endogenous estrogen and might reduce estrogen binding to estrogen receptors, resulting in an anti-estrogen effect. It is unclear if this effect transfers to exogenously administered estrogens.

Likelihood Possible Evidence D
Flaxseed full monograph & interactions

Fig3 drug types · 410 drugs

Antidiabetes Drugs

Theoretically, fig leaf might enhance the blood glucose lowering effects of hypoglycemic drugs.
A small clinical study in patients with type 1 diabetes shows that consuming a tea made from fig leaves modestly reduces postprandial glucose levels and insulin requirements.

Likelihood Probable Evidence B
Insulin

Fig leaf may enhance the blood glucose lowering effects of insulin.
A small clinical study in patients with type 1 diabetes shows that consuming a tea made from fig leaves modestly reduces postprandial glucose levels and insulin requirements.

Likelihood Probable Evidence B
Photosensitizing Drugs

Theoretically, fig might increase the risk of photosensitivity when used in combination with photosensitizing drugs.
Many cases of photodermatitis from fig leaf have been reported. Some drugs that also cause photosensitivity include amitriptyline (Elavil), quinolones (Ciprofloxacin, others), sulfa drugs (Septra, Bactrim, others), and tetracycline.

Likelihood Possible Evidence D
Fig full monograph & interactions

Sodium7 drug types · 205 drugs

Antihypertensive Drugs

Theoretically, a high intake of dietary sodium might reduce the effectiveness of antihypertensive drugs.
High intake of dietary sodium can increase systolic and diastolic blood pressure. Also, high intake of sodium may necessitate increased use of antihypertensive medications to achieve blood pressure control in some patients, such as those with chronic kidney disease.

Likelihood Probable Evidence A
Corticosteroids

Concomitant use of mineralocorticoids and some glucocorticoids with sodium supplements might increase the risk of hypernatremia.
Mineralocorticoids and some glucocorticoids (corticosteroids) cause sodium retention. This effect is dose-related and depends on mineralocorticoid potency. It is most common with hydrocortisone, cortisone, and fludrocortisone, followed by prednisone and prednisolone.

Likelihood Possible Evidence D
Didanosine (Videx)

Concomitant use of didanosine with additional sodium from dietary or supplemental sources may increase the risk of hypernatremia.
Didanosine formulations contain a significant amount of sodium.

Likelihood Probable Evidence C
Lithium

Altering dietary intake of sodium might alter the levels and clinical effects of lithium.
High sodium intake can reduce plasma concentrations of lithium by increasing lithium excretion. Reducing sodium intake can significantly increase plasma concentrations of lithium and cause lithium toxicity in patients being treated with lithium carbonate. Stabilizing sodium intake is shown to reduce the percentage of patients with lithium level fluctuations above 0.8 mEq/L. Patients taking lithium should avoid significant alterations in their dietary intake of sodium.

Likelihood Probable Evidence B
Sodium Phosphates

Theoretically, concomitant use of sodium phosphate with sodium supplements might increase the risk of hypernatremia.
Use of high doses (> 45 mL in 24 hours) of sodium phosphate, such as those used for bowel cleansing before surgery, can lead to serious electrolyte disturbances, including hypernatremia. The risk of hypernatremia is highest in the elderly and people with other risk factors for electrolyte disturbances.

Likelihood Possible Evidence D
Sodium-Containing Drugs

Concomitant use of sodium-containing drugs with additional sodium from dietary or supplemental sources may increase the risk of hypernatremia and long-term sodium-related complications.
The Chronic Disease Risk Reduction (CDRR) intake level of 2.3 grams of sodium daily indicates the intake at which it is believed that chronic disease risk increases for the apparently healthy population. Some medications contain high quantities of sodium. When used in conjunction with sodium supplements or high-sodium diets, the CDRR may be exceeded. Additionally, concomitant use may increase the risk for hypernatremia; this risk is highest in the elderly and people with other risk factors for electrolyte disturbances.

Likelihood Possible Evidence D
Tolvaptan (Samsca)

Theoretically, concomitant use of tolvaptan with sodium might increase the risk of hypernatremia.
Tolvaptan is a vasopressin receptor 2 antagonist that is used to increase sodium levels in patients with hyponatremia. Patients taking tolvaptan should use caution with the use of sodium salts such as sodium chloride.

Likelihood Probable Evidence C
Sodium full monograph & interactions

Pumpkin1 drug type · 1 drug

Lithium

Pumpkin might reduce excretion and increase levels of lithium.
Pumpkin is thought to have diuretic properties. Theoretically, this might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Probable Evidence D
Pumpkin full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Challenge, from the product label.

Loomis Enzymes

See all Loomis Enzymes products
Name
Loomis Enzymes, LLC
City
Fitchburg
State
Wisconsin
ZipCode
53719
Phone Number
1-800-614-4400
Web Address
www.loomisenzymes.com
Pharmacist Counseling Corner

Challenge by Loomis Enzymes: Common Questions

Does Challenge by Loomis Enzymes interact with any medications?
Yes. Based on its ingredients, Challenge has a known interaction with 2,205 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Challenge contains 10 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 blood pressure medication?
You need to check with your pharmacist first. Sodium in this product can reduce how well blood pressure medications work, and flaxseed may add to their effect and lower your blood pressure too much. These aren't safe combinations without professional advice.
Will this help with constipation?
Three of the ingredients—flaxseed, guar gum, and fig—are possibly effective for constipation based on our data. However, psyllium has not been checked in our database. Start with a small dose and drink lots of water, since these ingredients can cause bloating and gas.
Is this safe during pregnancy?
Safety varies by ingredient. Sodium is rated likely safe in pregnancy, but fig is also likely safe. Flaxseed and fennel are possibly unsafe in pregnancy; pumpkin and guar gum have limited data. Talk to your doctor or pharmacist for personalized advice before using this product while pregnant.
What's sodium doing in a digestive supplement?
Sodium is an essential mineral, but this product contains it as an ingredient rather than just from food. Too much sodium is linked to high blood pressure and heart strain. Unless your doctor told you to take sodium, you should ask your pharmacist whether it belongs in your routine.
Can I take this with my diabetes medication?
Flaxseed, fig, and guar gum all may lower blood sugar, so using them together with diabetes drugs or insulin could drop your blood sugar too low. Check with your pharmacist before starting.
What side effects should I expect?
Bloating, gas, diarrhea, and loose stools are the most common—these come mainly from the fiber ingredients like flaxseed and guar gum. Start with a small amount and increase gradually. Make sure to drink plenty of water, especially with guar gum, to avoid choking or bowel blockage.

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.

Challenge label
Go deeper

The Full Monographs Behind Challenge’s Ingredients

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

Herb & supplement monograph

Sodium

Interacts with 205 drugs

Sodium is an essential mineral and electrolyte your body needs to balance fluids, support nerves, and help muscles work. Most people in modern diets get more than enough—often too much—from...

Read the full Sodium monograph → 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

Flaxseed

Interacts with 597 drugs

Flaxseed is a nutritious food rich in fiber, omega-3 fats (ALA), and plant compounds called lignans. It is most reliably helpful for constipation and may modestly lower cholesterol, but evid...

Read the full Flaxseed monograph → Herb & supplement monograph

Fig

Interacts with 410 drugs

Fig (Ficus carica) is a common fruit that has long been used as a gentle food remedy for constipation, and its leaves are used traditionally for blood sugar and coughs. The fruit is a safe a...

Read the full Fig monograph → Herb & supplement monograph

Fennel

Interacts with 740 drugs

Fennel is a Mediterranean herb widely used as a food and spice, and traditionally taken for digestive complaints, colic, and menstrual cramps. Some small studies suggest possible benefit for...

Read the full Fennel monograph → Herb & supplement monograph

Pumpkin

Interacts with 1 drug

Pumpkin is a nutritious squash, and its seeds and seed oil are the parts most often used as supplements, mainly for urinary and prostate symptoms. The evidence for these uses is limited and...

Read the full Pumpkin monograph → Herb & supplement monograph

Guar Gum

Interacts with 2,025 drugs

Guar gum is a soluble, gel-forming fiber from the guar bean that may modestly help with cholesterol, blood sugar, and bowel regularity. It is generally safe in food amounts, but concentrated...

Read the full Guar Gum monograph →
Sources

Sources & How We Checked

Challenge'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 154 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.

Sodium 38 references
  1. Garabedian-Ruffalo SM, Ruffalo RL. Drug and nutrient interactions. Am Fam Physician 1986;33:165-74.
  2. Food and Drug Administration Science Background: Safety of Sodium Phosphates Oral Solution. September 17, 2001. Available at: http://www.fda.gov/cder/drug/safety/sodiumphospate.htm
  3. Coton T, Mallaret C, Coilliot C, Carre D, Guisset M. Severe acute ulcerated gastritis induced by salt. Presse Med 2009;38(3):499-500. PubMed
  4. Frings-Meuthen P, Buehlmeier J, Baecker N, et al. High sodium chloride intake exacerbates immobilization-induced bone resorption and protein losses. J Appl Physiol 2011;111(2):537-542. PubMed
  5. Frings-Meuthen P, Baecker N, Heer M. Low-grade metabolic acidosis may be the cause of sodium chloride-induced exaggerated bone resorption. J Bone Miner Res 2008;23(4):517-524. PubMed
  6. Alam S, Johnson AG. A meta-analysis of randomised controlled trials (RCT) among healthy normotensive and essential hypertensive elderly patients to determine the effect of high salt (NaCl) diet of blood pressure. J Hum Hypertens 1999;13(6):367-74.
  7. Boudville N, Ward S, Benaroia M, House AA. Increased sodium intake correlates with greater use of antihypertensive agents by subjects with chronic kidney disease. Am J Hypertens 2005;18(10):1300-5. PubMed
  8. Bennett WM. Drug interactions and consequences of sodium restriction. Am J Clin Nutr 1997;65(2 Suppl):678S-681S. PubMed
  9. Okusa MD, Crystal LJ. Clinical manifestations and management of acute lithium intoxication. Am J Med 1994;97(4):383-9. PubMed
  10. Food and Nutrition Board, Institute of Medicine. Dietary reference intakes for water, potassium, sodium, chloride, and sulfate. Washington, DC: National Academy Press, 2005. Available at: http://www.nap.edu/openbook.php?record_id=10925. DOI
  11. D'Elia L, Rossi G, Ippolito R, Cappuccio FP, Strazzullo P. Habitual salt intake and risk of gastric cancer: a meta-analysis of prospective studies. Clin Nutr 2012;31(4):489-98. PubMed
  12. Goldsmith SR. Hyponatremia in heart failure: time for a trial. J Card Fail 2013;19(6):398-400. PubMed
  13. Willocks L, Brettle R, Keen J, Valentine C, Pinching AJ. Formulations of didanosine (ddI) and salt overload. Lancet 1992;339(8786):190.
  14. Chen L, Zhang Z, Chen W, Whelton PK, Appel LJ. Lower Sodium Intake and Risk of Headaches: Results From the Trial of Nonpharmacologic Interventions in the Elderly. Am J Public Health. 2016;106(7):1270-5. PubMed
  15. Cook NR, Appel LJ, Whelton PK. Lower levels of sodium intake and reduced cardiovascular risk. Circulation. 2014;129(9):981-9. PubMed
  16. Cook NR, Appel LJ, Whelton PK. Sodium Intake and All-Cause Mortality Over 20 Years in the Trials of Hypertension Prevention. J Am Coll Cardiol. 2016;68(15):1609-1617. PubMed
  17. Mente A, O'Donnell M, Rangarajan S, et al. Associations of urinary sodium excretion with cardiovascular events in individuals with and without hypertension: a pooled analysis of data from four studies. Lancet. 2016;388(10043):465-75. PubMed
  18. Moosavian SP, Haghighatdoost F, Surkan PJ, Azadbakht L. Salt and obesity: a systematic review and meta-analysis of observational studies. Int J Food Sci Nutr. 2017;68(3):265-277. PubMed
  19. O'Donnell M, Mente A, Rangarajan S, et al. Urinary sodium and potassium excretion, mortality, and cardiovascular events. N Engl J Med. 2014;371(7):612-23. DOI
  20. Poggio R, Gutierrez L, Matta MG, Elorriaga N, Irazola V, Rubinstein A. Daily sodium consumption and CVD mortality in the general population: systematic review and meta-analysis of prospective studies. Public Health Nutr. 2015;18(4):695-704. PubMed
  21. Stallings VA, Harrison M, Oria M; Committee to Review the Dietary Reference Intakes for Sodium and Potassium, Food and Nutrition Board, Health and Medicine Division, National Academies of Sciences, Engineering, and Medicine. Washington (DC): National Acad
  22. Mahtani KR, Heneghan C, Onakpoya I, et al. Reduced Salt Intake for Heart Failure: A Systematic Review. JAMA Intern Med. 2018 Dec 1;178(12):1693-1700. PubMed
  23. Yancy CW. Sodium Restriction in Heart Failure: Too Much Uncertainty-Do the Trials. JAMA Intern Med. 2018 Dec 1;178(12):1700-1701. PubMed
  24. He FJ, Campbell NRC, Ma Y, MacGregor GA, Cogswell ME, Cook NR. Errors in estimating usual sodium intake by the Kawasaki formula alter its relationship with mortality: implications for public health. Int J Epidemiol. 2018;47(6):1784-1795. PubMed
  25. Murthy K, Ondrey GJ, Malkani N, et al. THE EFFECTS OF HYPONATREMIA ON BONE DENSITY AND FRACTURES: A SYSTEMATIC REVIEW AND META-ANALYSIS. Endocr Pract. 2019;25(4):366-378. PubMed
  26. Messerli FH, Hofstetter L, Syrogiannouli L, et al. Sodium intake, life expectancy, and all-cause mortality. Eur Heart J 2021;42(21):2103-2112. PubMed
  27. Graudal NA, Hubeck-Graudal T, Jurgens G. Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride. Cochrane Database Syst Rev 2020;12(12):CD004022. PubMed
  28. Giatti S, Santos RB, Aielo AN, et al. Association of sodium with obstructive sleep apnea. The ELSA-Brasil study. Ann Am Thorac Soc 2021;18(3):502-510. PubMed
  29. Nan X, Lu H, Wu J, et al. The interactive association between sodium intake, alcohol consumption and hypertension among elderly in northern China: a cross-sectional study. BMC Geriatr 2021;21(1):135. PubMed
  30. Kyozuka H, Fukusda T, Murata T, et al. Impact of preconception sodium intake on hypertensive disorders of pregnancy: The Japan Environment and Children's study. Pregnancy Hypertens 2021;23:66-72. PubMed
  31. Zhao L, Ogden CL, Yang Q, et al. Association of usual sodium intake with obesity among US children and adolescents, NHANES 2009-2016. Obesity (Silver Spring) 2021;29(3):587-594. PubMed
  32. Ma Y, He FJ, Sun Q, et al. 24-Hour urinary sodium and potassium excretion and cardiovascular risk. N Engl J Med 2022;386(3):252-263. PubMed
  33. Liu J, Yang X, Zhang P, et al. Association of urinary sodium excretion and left ventricular hypertrophy in people with type 2 diabetes mellitus: A cross-sectional study. Front Endocrinol (Lausanne) 2021;12:728493. PubMed
  34. Filippini T, Malavolti M, Whelton PK, Vinceti M. Sodium intake and risk of hypertension: A systematic review and dose-response meta-analysis of observational cohort studies. Curr Hypertens Rep 2022;24(5):133-144. PubMed
  35. Wang DD, Li Y, Nguyen XT, et al. Dietary sodium and potassium intake and risk of non-fatal cardiovascular diseases: The million veteran program. Nutrients 2022;14(5):1121. PubMed
  36. Kwak JH, Park CH, Eun CS, et al. The associations of dietary intake of high sodium and low zinc with gastric cancer mortality: A prospective cohort study in Korea. Nutr Cancer 2022;74(10):3501-3508. PubMed
  37. George S, Maiti R, Mishra BR, Jena M, Mohapatra D. Effect of regulated add-on sodium chloride intake on stabilization of serum lithium concentration in bipolar disorder: A randomized controlled trial. Bipolar Disord 2023;25(1):66-75. PubMed
  38. Zhou TL, Schütten MTJ, Kroon AA, et al. Urinary Sodium Excretion and Salt Intake Are Not Associated With Blood Pressure Variability in a White General Population. J Am Heart Assoc 2023;12(1):e026578. PubMed

See these in context on the Sodium monograph →

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
  16. Diez R, Garcia JJ, Diez MJ, Sierra M, Sahagun AM, Fernandez N. Influence of Plantago ovata husk (dietary fiber) on the bioavailability and other pharmacokinetic parameters of metformin in diabetic rabbits. BMC Complement Altern Med. 2017 Jun 7;17(1):298. PubMed
  17. Chiu AC, Sherman SI. Effects of pharmacological fiber supplements on levothyroxine absorption. Thyroid. 1998;8(8):667-71. PubMed
  18. Merrick C, Madden CA, Capurso NA. A Case of Blunted Orally Disintegrating Olanzapine Effect Due to Coadministered Psyllium. J Clin Psychiatry 2021;82(2):20cr13633. PubMed

See these in context on the Black Psyllium monograph →

Flaxseed 37 references
  1. Kolonel LN, Nomura AM, Cooney RV. Dietary fat and prostate cancer: current status. J Natl Cancer Inst 1999;91:414-28. PubMed
  2. Ramon JM, Bou R, Romea S, et al. Dietary fat intake and prostate cancer risk: a case-control study in Spain. Cancer Causes Control 2000;11:679-85. PubMed
  3. Thompson LU, Rickard SE, Cheung F, et al. Variability in anticancer lignan levels in flaxseed. Nutr Cancer 1997;27:26-30. PubMed
  4. Nordstrom DC, Honkanen VE, Nasu Y, et al. Alpha-linolenic acid in the treatment of rheumatoid arthritis. A double-blind, placebo-controlled and randomized study: flaxseed vs. safflower seed. Rheumatol Int 1995;14:231-4. PubMed
  5. Cunnane SC, Ganguli S, Menard C, et al. High alpha-linolenic acid flaxseed (Linum usitatissimum): some nutritional properties in humans. Br J Nutr 1993;69:443-53.
  6. Clark WF, Parbtani A, Huff MW, et al. Flaxseed: a potential treatment for lupus nephritis. Kidney Int 1995;48:475-80. PubMed
  7. Cunnane SC, Hamadeh MJ, Liede AC, et al. Nutritional attributes of traditional flaxseed in healthy young adults. Am J Clin Nutr 1995;61:62-8. PubMed
  8. De Stefani E, Deneo-Pellegrini H, Boffetta P, et al. Alpha-linolenic acid and risk of prostate cancer: a case-control study in Uruguay. Cancer Epidemiol Biomarkers Prev 2000;9:335-8.
  9. Giovannucci E, Rimm EB, Colditz GA, et al. A prospective study of dietary fat and risk of prostate cancer. J Natl Cancer Inst 1993;85:1571-9. PubMed
  10. Clark WF, Kortas C, Heidenheim P, et al. Flaxseed in lupus nephritis: a two-year nonplacebo-controlled crossover study. J Am Coll Nutr 2001;20:143-8. PubMed
  11. Serraino M, Thompson LU. The effect of flaxseed supplementation on early risk markers for mammary carcinogenesis. Cancer Lett 1991;60:135-42. PubMed
  12. Rickard SE, Yuan YV, Thompson LU. Plasma insulin-like growth factor I levels in rats are reduced by dietary supplementation of flaxseed or its lignan secoisolariciresinol diglycoside. Cancer Lett 2000;161:47-55. PubMed
  13. Mousavi Y, Adlercreutz H. Enterolactone and estradiol inhibit each other's proliferative effect on MCF-7 breast cancer cells in culture. J Steroid Biochem Mol Biol 1992;41:615-9.. PubMed
  14. Adlercreutz H, Fotsis T, Bannwart C, et al. Determination of urinary lignans and phytoestrogen metabolites, potential antiestrogens and anticarcinogens, in urine of women on various habitual diets. J Steroid Biochem 1986;25:791-7.. PubMed
  15. Rose DP. Dietary fiber and breast cancer. Nutr Cancer 1990;13:1-8.. PubMed
  16. Lemay A, Dodin S, Kadri N, et al. Flaxseed dietary supplement versus hormone replacement therapy in hypercholesterolemic menopausal women. Obstet Gynecol 2002;100:495-504.. DOI
  17. Brooks JD, Ward WE, Lewis JE, et al. Supplementation with flaxseed alters estrogen metabolism in postmenopausal women to a greater extent than does supplementation with an equal amount of soy. Am J Clin Nutr 2004;79:318-25.. PubMed
  18. Laaksonen DE, Laukkanen JA, Niskanen L, et al. Serum linoleic and total polyunsaturated fatty acids in relation to prostate and other cancers: a population-based cohort study. Int J Cancer 2004;111:444-50.. PubMed
  19. Dodin S, Lemay A, Jacques H, et al. The effects of flaxseed dietary supplement on lipid profile, bone mineral density, and symptoms in menopausal women: a randomized, double-blind, wheat germ placebo-controlled clinical trial. J Clin Endocrinol Metab 2005 PubMed
  20. Brouwer IA, Katan MB, Zock PL. Dietary alpha-linolenic acid is associated with reduced risk of fatal coronary heart disease, but increased prostate cancer risk: a meta-analysis. J Nutr 2004;134:919-22.
  21. Demark-Wahnefried W, Polascik TJ, George SL, et al. Flaxseed supplementation (not dietary fat restriction) reduces prostate cancer proliferation rates in men presurgery. Cancer Epidemiol Biomarkers Prev 2008;17:3577-87. PubMed
  22. Thompson LU, Chen JM, Li T, et al. Dietary flaxseed alters tumor biological markers in postmenopausal breast cancer. Clin Cancer Res 2005;11:3828-35. PubMed
  23. Mani UV, Mani I, Biswas M, Kumar SN. An open-label study on the effect of flax seed powder (Linum usitatissimum) supplementation in the management of diabetes mellitus. J Diet Suppl 2011;8:257-65.
  24. Rhee Y, Brunt A. Flaxseed supplementation improved insulin resistance in obese glucose intolerant people: a randomized crossover design. Nutr J 2011;10:44. PubMed
  25. Cornish SM, Chilibeck PD, Paus-Jennsen L, et al. A randomized controlled trial of the effects of flaxseed lignan complex on metabolic syndrome composite score and bone mineral in older adults. Appl Physiol Nutr Metab 2009;34:89-98. PubMed
  26. Cockerell KM, Watkins AS, Reeves LB, et al. Effects of linseeds on the symptoms of irritable bowel syndrome: a pilot randomised controlled trial. J Hum Nutr Diet 2012;25:435-43. PubMed
  27. Colli MC, Bracht A, Soares AA, et al. Evaluation of the efficacy of flaxseed meal and flaxseed extract in reducing menopausal symptoms. J Med Food 2012;15:840-5. PubMed
  28. Allman, M. A., Pena, M. M., and Pang, D. Supplementation with flaxseed oil versus sunflowerseed oil in healthy young men consuming a low fat diet: effects on platelet composition and function. Eur.J Clin.Nutr. 1995;49(3):169-178.
  29. Simbalista RL, Sauerbronn AV, Aldrighi JM, Areas JA. Consumption of a flaxseed-rich food is not more effective than a placebo in alleviating the climacteric symptoms of postmenopausal women. J Nutr 2010;140:293-7. PubMed
  30. Patade A, Devareddy L, Lucas EA, et al. Flaxseed reduces total and LDL cholesterol concentrations in Native American postmenopausal women. J Womens Health (Larchmt) 2008;17:355-66. PubMed
  31. Rodriguez-Leyva D, Weighell W, Edel AL, LaVallee R, Dibrov E, Pinneker R, Maddaford TG, Ramjiawan B, Aliani M, Guzman R, Pierce GN. Potent antihypertensive action of dietary flaxseed in hypertensive patients. Hypertension. 2013 Dec;62(6):1081-9. PubMed
  32. Bloedon LT, Balikai S, Chittams J, et al. Flaxseed and cardiovascular risk factors: results from a double blind, randomized, controlled clinical trial. J Am Coll Nutr 2008;27:65-74. PubMed
  33. Ursoniu S, Sahebkar A, Andrica F, Serban C, Banach M; Lipid and Blood Pressure Meta-analysis Collaboration Group. Effects of flaxseed supplements on blood pressure: a systematic review and meta-analysis of controlled clinical trial. Clin Nutr. 2016 Jun;3 PubMed
  34. Mohammadi-Sartang M, Sohrabi Z, Barati-Bodaji R, Raeisi-Dehkordi H, Mazloom Z. Flaxseed supplementation on glucose control and insulin sensitivity: a systematic review and meta-analysis of 25 randomized, placebo-controlled trials. Nutr Rev. 2018 Feb 1;76( PubMed
  35. Haidari F, Banaei-Jahromi N, Zakerkish M, Ahmadi K. The effects of flaxseed supplementation on metabolic status in women with polycystic ovary syndrome: a randomized open-labeled controlled clinical trial. Nutr J. 2020;19(1):8. PubMed
  36. Villarreal-Renteria AI, Herrera-Echauri DD, Rodríguez-Rocha NP, et al. Effect of flaxseed (Linum usitatissimum) supplementation on glycemic control and insulin resistance in prediabetes and type 2 diabetes: A systematic review and meta-analysis of randomi
  37. Li L, Li H, Gao Y, Vafaei S, Zhang X, Yang M. Effect of flaxseed supplementation on blood pressure: a systematic review, and dose-response meta-analysis of randomized clinical trials. Food Funct 2023;14(2):675-690. PubMed

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Fig 13 references
  1. Gandolfo M, Baeza M, De Barrio M, Anaphylaxis after eating figs. Allergy 2001;56:462-3. PubMed
  2. Serraclara A, Hawkins F, Perez C, et al. Hypoglycemic action of an oral fig-leaf decoction in type-I diabetic patients. Diabetes Res Clin Pract 1998;39:19-22. PubMed
  3. Rubnov S, Kashman Y, Rabinowitz R, et al. Suppressors of cancer cell proliferation from fig (Ficus carica) resin: isolation and structure elucidation. J Nat Prod 2001;64:993-6.
  4. Dechamp C, Bessot JC, Pauli G, Deviller P. First report of anaphylactic reaction after fig (Ficus carica) ingestion. Allergy 1995;50:514-6.
  5. Zaynoun ST, Aftimos BG, Abi Ali L, et al. Ficus carica; isolation and quantification of the photoactive components. Contact Dermatitis 1984;11:21-5.
  6. Lembo G, Lo Presti M, Balato N. Phytophotodermatitis due to ficus carica. Photodermatol 1985;2:119-20.
  7. Bollero, D., Stella, M., Rivolin, A., Cassano, P., Risso, D., and Vanzetti, M. Fig leaf tanning lotion and sun-related burns: case reports. Burns 2001;27(7):777-779. PubMed
  8. Ozdamar, E., Ozbek, S., and Akin, S. An unusual cause of burn injury: fig leaf decoction used as a remedy for a dermatitis of unknown etiology. J.Burn Care Rehabil. 2003;24(4):229-233. PubMed
  9. Munteanu, M. Contact dermatitis to the sap of fig-tree. Rev.Med.Chir Soc.Med.Nat.Iasi 1989;93(3):602.
  10. Lembo, G., Lo, Presti M., and Balato, N. Phytophotodermatitis due to ficus carica. Photodermatol. 1985;2(2):119-120.
  11. Micali, G., Nasca, M. R., and Musumeci, M. L. Severe phototoxic reaction secondary to the application of a fig leaves' decoction used as a tanning agent. Contact Dermatitis 1995;33(3):212-213. PubMed
  12. Bonamonte D, Foti C, Lionetti N, Rigano L, Angelini G. Photoallergic contact dermatitis to 8-methoxypsoralen in Ficus carica. Contact Dermatitis. 2010;62(6):343-8.
  13. Pinto AR, Machado Cunha I, Rebelo Gomes E. Fig Tree-Induced Phytophotodermatitis: A Case Report on the Perils of a Hobby. Cureus 2023;15(7):e41888. PubMed

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Fennel 17 references
  1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  3. Zhu M, Wong PY, Li RC. Effect of oral administration of fennel (Foeniculum vulgare) on ciprofloxacin absorption and disposition in the rat. J Pharm Pharmacol 1999;51:1391-6.
  4. Gral N, Beani JC, Bonnot D, et al. [Plasma levels of psoralens after celery ingestion]. Ann Dermatol Venereol 1993;120:599-603.
  5. Burkhard PR, Burkhardt K, Haenggeli CA, Landis T. Plant-induced seizures: reappearance of an old problem. J Neurol 1999;246:667-70. PubMed
  6. Rosti L, Nardini A, Bettinelli ME, Rosti D. Toxic effects of a herbal tea mixture in two newborns. Acta Paediatrica 1994;83:683. PubMed
  7. Cuzzolin L, Zaffani S, and Benoni G. Safety implications regarding use of phytomedicines. Eur.J Clin Pharmacol. 2006;62:37-42. PubMed
  8. Tognolini, M., Ballabeni, V., Bertoni, S., Bruni, R., Impicciatore, M., and Barocelli, E. Protective effect of Foeniculum vulgare essential oil and anethole in an experimental model of thrombosis. Pharmacol.Res 2007;56(3):254-260. PubMed
  9. Subehan, Usia, T., Iwata, H., Kadota, S., and Tezuka, Y. Mechanism-based inhibition of CYP3A4 and CYP2D6 by Indonesian medicinal plants. J Ethnopharmacol. 5-24-2006;105(3):449-455. PubMed
  10. Tognolini, M., Barocelli, E., Ballabeni, V., Bruni, R., Bianchi, A., Chiavarini, M., and Impicciatore, M. Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity. Life Sci. 2-23-2006;78(13):1419-1432. PubMed
  11. Subehan, Zaidi, S. F., Kadota, S., and Tezuka, Y. Inhibition on human liver cytochrome P450 3A4 by constituents of fennel (Foeniculum vulgare): identification and characterization of a mechanism-based inactivator. J Agric.Food Chem. 12-12-2007;55(25):101 PubMed
  12. LEVY, S. B. Bronchial asthma due to ingestion of fennel and fennel seed. Ann.Allergy 1948;6(4):415.
  13. Ottolenghi, A., De Chiara, A., Arrigoni, S., Terracciano, L., and De Amici, M. [Diagnosis of food allergy caused by fruit and vegetables in children with atopic dermatitis]. Pediatr Med Chir 1995;17(6):525-530.
  14. Trabace L, Tucci P, Ciuffreda L, et al. "Natural" relief of pregnancy-related symptoms and neonatal outcomes: above all do no harm. J Ethnopharmacol. 2015;174:396-402. PubMed
  15. Denaxa D, Arkwright PD. Fennel as a cause of immediate hypersensitivity to toothpaste. Ann Allergy Asthma Immunol. 2020;125(1):99-100. PubMed
  16. Lee HW, Ang L, Lee MS, Alimoradi Z, Kim E. Fennel for reducing pain in primary dysmenorrhea: a systematic review and meta-analysis of randomized controlled trials. Nutrients 2020;12(11):3438. PubMed
  17. Mathew T, John SK, Javali M, Vasireddy M, Nadig R, Sarma GRK. Substance use related cluster headache: A case series. Headache 2022;62(7):908-910. PubMed

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Pumpkin 5 references
  1. Marks L, Partin AW, Epstein JI, et al. Effects of a saw palmetto herbal blend in men with symptomatic benign prostatic hyperplasia. J Urol 2000;163:1451-6. DOI
  2. Cho YH, Lee SY, Jeong DW, et al. Effect of pumpkin seed oil on hair growth in men with androgenetic alopecia: a randomized, double-blind, placebo-controlled trial. Evid Based Complement Alternat Med 2014;2014:549721. PubMed
  3. Vahlensieck W, Theurer C, Pfitzer E, Patz B, Banik N, Engelmann U. Effects of pumpkin seed in men with lower urinary tract symptoms due to benign prostatic hyperplasia in the one-year, randomized, placebo-controlled GRANU study. Urol Int 2015;94(3):286-95 PubMed
  4. Assouly P. Hair loss associated with cucurbit poisoning. JAMA Dermatol. 2018 May 1;154(5):617-618. PubMed
  5. Gawryjolek J, Ludwig H, Zbikowska-Götz M, Bartuzi Z, Krogulska A. Anaphylaxis after consumption of pumpkin seeds in a 2-y-old child tolerant to its pulp: A case study. Nutrition 2021;89:111272. PubMed

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Guar Gum 26 references
  1. Gin H, Orgerie MB, Aubertin J. The influence of Guar gum on absorption of metformin from the gut in healthy volunteers. Horm Metab Res 1989;21:81-3.
  2. Huupponen R, Seppala P, Iisalo E. Effect of guar gum, a fibre preparation, on digoxin and penicillin absorption in man. Eur J Clin Pharmacol 1984;26:279-81. PubMed
  3. Malo JL, Cartier A, L'Archeveque J, et al. Prevalence of occupational asthma and immunologic sensitization to guar gum among employees at a carpet-manufacturing plant. J Allergy Clin Immunol 1990;86:562-9. PubMed
  4. Lagier F, Cartier A, Somer J, et al. Occupational asthma caused by guar gum. J Allergy Clin Immunol 1990;85:785-90.
  5. Lewis JH. Esophageal and small bowel obstruction from guar gum-containing diet pills: analysis of 26 cases reported to the FDA. Am J Gastroenterol 1992;87:1424-8.
  6. Vuorinen-Markkola H, Sinisalo M, Koivisto VA. Guar gum in insulin-dependent diabetes: effects on glycemic control and serum lipoproteins. Am J Clin Nutr 1992;56:1056-1060. PubMed
  7. Superko HR, Haskell WL, Sawrey-Kubicek L, Farquhar JW. Effects of solid and liquid guar gum on plasma cholesterol and triglyceride concentrations in moderate hypercholesterolemia. Am J Cardiol 1988;62:51-5. PubMed
  8. 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
  9. Groop PH, Aro A, Stenman S, Groop L. Long-term effects of guar gum in subjects with non-insulin-dependent diabetes mellitus. Am J Clin Nutr 1993;58:513-8. PubMed
  10. Chuang LM, Jou TS, Yang WS, et al. Therapeutic effect of guar gum in patients with non-insulin-dependent diabetes mellitus. J Formos Med Assoc 1992;91:15-9.
  11. Ebeling P, Yki-Jarvinen H, Aro A, et al. Glucose and lipid metabolism and insulin sensitivity in type 1 diabetes: the effect of guar gum. Am J Clin Nutr 1988;48:98-103. PubMed
  12. Scheen AJ. Clinical pharmacokinetics of metformin. Clin Pharmacokinet 1996;30:359-71. PubMed
  13. Knopp RH, Superko HR, Davidson M, et al. Long-term blood cholesterol-lowering effects of a dietary fiber supplement. Am J Prev Med 1999;17:18-23. PubMed
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  17. Riikonen, S., Savonius, H., Gylling, H., Nikkila, K., Tuomi, A. M., and Miettinen, T. A. Oral guar gum, a gel-forming dietary fiber relieves pruritus in intrahepatic cholestasis of pregnancy. Acta Obstet.Gynecol.Scand. 2000;79(4):260-264. DOI
  18. Kovacs, E. M., Westerterp-Plantenga, M. S., Saris, W. H., Goossens, I., Geurten, P., and Brouns, F. The effect of addition of modified guar gum to a low-energy semisolid meal on appetite and body weight loss. Int.J.Obes.Relat Metab Disord. 2001;25(3):307 PubMed
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See these in context on the Guar Gum 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.

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