Interactions on record — worth a quick check against your medications. Based on 5 of 8 ingredients. Check your meds →
Dietary supplement

Seasonal Clear Ingredients & Drug Interactions

by Priority One Nutritional Supplements

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

First and foremost: checking Seasonal Clear 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

Seasonal Clear is a dietary supplement by Priority One Nutritional Supplements with 8 active ingredients. Its ingredients are commonly taken for inflammation and swelling, sinus and nasal congestion, digestion support.Based on those ingredients, 1,062 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Echinacea, Stinging Nettle, Bromelain. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Seasonal Clear by Priority One Nutritional Supplements

Ask about any prescription or over-the-counter medication and we check it for interactions with Seasonal Clear by Priority One Nutritional Supplements — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Seasonal Clear by Priority One Nutritional Supplements

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

From our pharmacy team — supplement deep dive

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

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 8 of its 8 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Seasonal Clear has 8 ingredients total. The active ones are bromelain (an enzyme from pineapple), protease and lipase (digestive enzymes), stinging nettle leaf, echinacea, and bioflavonoids (plant compounds).

Amylase and cellulase are also digestive enzymes. The capsule itself is made with rice flour, hypromellose, and purified water.

Does it work?

Insufficient 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
Insufficient

There isn't enough reliable clinical evidence to rate this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Seasonal allergies and respiratory support.
  • We looked for evidence on: Allergic rhinitis (hay fever), Rhinosinusitis, Upper respiratory tract infection (URTI), Exercise-induced respiratory infections, Nasal congestion, Sinus support — and 1 related terms.
  • The closest evidence on file: Stinging Nettle is rated "Insufficient Reliable Evidence To Rate" for Allergic rhinitis (hay fever) (Natural Medicines).
  • Also on file: Bromelain is rated "Insufficient Reliable Evidence To Rate" for Allergic rhinitis (hay fever), Exercise-induced respiratory infections, Rhinosinusitis.
  • Also on file: Echinacea is rated "Insufficient Reliable Evidence To Rate" for Upper respiratory tract infection (URTI).

The evidence for most of these ingredients is thin. Bromelain shows insufficient reliable evidence for hay fever, burns, cancer, nerve damage from chemotherapy, chronic venous insufficiency, and diabetes.

Stinging nettle is possibly effective for diabetes but has insufficient evidence for hay fever, anemia, asthma, prostate issues, and gum disease. Protease and lipase have insufficient evidence for inflammatory bowel disease and indigestion.

Echinacea also carries insufficient evidence across anxiety, athletic performance, ADHD, burns, chronic fatigue, and migraines. Bioflavonoids have no effectiveness data on file.

The evidence, ingredient by ingredient Bromelain Proteolytic Enzymes (proteases) Lipase Stinging Nettle Echinacea

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 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Bromelain is generally well tolerated in the short term but long-term safety data is limited. The most common side effects are diarrhea, flatulence, stomach upset, and headache.

Allergic reactions are rare but possible, especially if you're sensitive to pineapple or have pollen allergies. Stinging nettle is generally well tolerated when used as directed and most commonly causes constipation or diarrhea.

Echinacea is well tolerated short-term but can trigger allergic reactions, particularly in people sensitive to ragweed and related plants; rare cases of echinacea-induced liver inflammation have been reported. Protease and lipase are generally well tolerated but may cause digestive upset or, rarely, allergic reactions.

Side effects, ingredient by ingredient Bromelain Proteolytic Enzymes (proteases) Lipase Stinging Nettle Echinacea

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

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

Why this rating?
  • 3 of the 5 matched ingredients can interact with medications — Stinging Nettle, Bromelain, Echinacea.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; lithium.
  • For scale: 1,063 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.

Check with us before taking this if you're on anticoagulants or antiplatelets (blood thinners or aspirin), antidiabetes drugs, diuretics, lithium, warfarin, immunosuppressants, etoposide, or caffeine supplements. Also confirm with your pharmacist if you take any drugs metabolized by your liver's CYP1A2 or CYP3A4 enzymes — that's a very large list.

These are the main interactions our data shows.

Check your own medication Run your meds through the checker above

The bottom line

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

Seasonal Clear may appeal to someone looking for enzyme and herbal support during allergy season, but it carries real interactions with blood thinners, diabetes medications, lithium, and several other drug types. If you take any prescription medications — especially for bleeding, blood sugar control, or mood — talk to your pharmacist before starting this product.

The evidence that these ingredients actually work for their intended purpose is mostly insufficient.

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

Assessment coverage: 5 of 8 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated May 23, 2024.

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

At a glance

General information

Key facts about Seasonal Clear, straight from the product label.

Brand Priority One Nutritional Supplements
Barcode (UPC) 815354021225
Net contents 90 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD May 23, 2024
DSLD ID 310780
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegetarian, 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 Seasonal Clear by Priority One Nutritional Supplements, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Vegetarian Capsule(s)
Maximum serving Sizes:
1 Vegetarian Capsule(s)
Servings per container
90
UPC/BARCODE
815354021225
IngredientAmount% DV
Amylase50 mg--
Bromelain71 mg--
Protease60 mg--
Lipase30 mg--
Cellulase23 mg--
Stinging Nettle75 mg--
Echinacea75 mg--
Bioflavonoids100 mg--

Other ingredients: Rice Flour, Hypromellose, Water, Purified

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.
Precautions

Warning: If you are pregnant or breast feeding, consult your physician before using this product.

Keep out of reach of children.

For professional use only.

Suggested/Recommended/Usage/Directions

Recommendations: Take one (1) capsule between meals three times daily, or as directed by your physician.

Storage

Keep container tightly closed, store in a cool, dry place.

Formulation

Contains no preservatives. Bisphenol-A (BPA) & Phthalate Free

Vegetarian formulation

Non-GMO

Seals/Symbols

GMP Certified

Brand IP Statement(s)

Priority One Nutritional Supplements Inc. Since 1988

FDA Statement of Identity

A Dietary Supplement

FDA Disclaimer Statement

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

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

See for yourself

Seasonal Clear by Priority One Nutritional Supplements label

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

Seasonal Clear 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 Seasonal Clear by Priority One Nutritional Supplements

These are the 8 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Vegetarian Capsule(s) Dosage formCapsule Servings per container90 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.

Amylase

50 mg per serving

Bromelain

Interacts with
141 drugs
71 mg per serving

Bromelain is a group of protein-digesting enzymes from pineapple that people take mainly for inflammation, swelling, and sinus problems. Some early st...

Bromelain monograph & interactions

Protease

No known
interactions
60 mg per serving

Proteolytic enzymes are proteins that help break down other proteins, and common examples include bromelain (from pineapple), papain (from papaya), tr...

Protease monograph & interactions

Lipase

No known
interactions
30 mg per serving

Lipase is a digestive enzyme that helps your body break down dietary fats. It is well established as part of prescription pancreatic enzyme therapy fo...

Lipase monograph & interactions

Cellulase

23 mg per serving

Stinging Nettle

Interacts with
164 drugs
75 mg per serving

Stinging nettle is a common plant used as food and in traditional medicine, most often for prostate symptoms, allergies, and joint pain. The evidence...

Stinging Nettle monograph & interactions

Echinacea

Interacts with
816 drugs
75 mg per serving Form: Echinacea purpurea

Echinacea is a popular herb taken to help prevent or shorten the common cold, but study results are mixed and the overall benefit appears small at bes...

Echinacea monograph & interactions

Bioflavonoids

100 mg per serving Form: Bitter Orange Fruit Extract

Other (inactive) ingredients: Rice Flour, Hypromellose, Water, Purified. These complete the product’s ingredient list but are not active constituents.

Interaction report

Seasonal Clear by Priority One Nutritional Supplements Drug Interactions

Want to check YOUR meds against Seasonal Clear?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
1,062Drugs
1,043 Moderate 19 Minor

Ingredients driving the most interactions

Echinacea 816
Stinging Nettle 164
Bromelain 141

Individual Drug Interactions

The ingredients in Seasonal Clear interact with 1,062 drugs. Click any drug to see the details.

3 of the 8 ingredients in Seasonal Clear interact with drugs. Each result below shows which ingredient is responsible. Echinacea Stinging Nettle Bromelain

Each ingredient & the kinds of drugs it affects

For each ingredient in Seasonal Clear 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.

Echinacea12 drug types · 816 drugs

Caffeine

Echinacea can increase plasma levels of caffeine by inhibiting its metabolism.
Echinacea seems to increase plasma concentrations of caffeine by around 30%. This is likely due to inhibition of cytochrome P450 1A2 (CYP1A2) by echinacea.

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

Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Echinacea appears to inhibit CYP1A2 enzymes in humans. Additionally, echinacea seems to increase plasma concentrations of caffeine, a CYP1A2 substrate, by around 30%. Theoretically, echinacea might increase levels of other drugs metabolized by CYP1A2.

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

Echinacea may induce hepatic CYP3A4 and inhibit intestinal CYP3A4. This may increase or decrease levels of drugs metabolized by CYP3A4.
Several clinical trials have shown that taking echinacea for up to one month does not significantly affect the metabolism of various CYP3A4 substrates, including midazolam, docetaxel, etravirine, lopinavir-ritonavir, and darunavir-ritonavir. However, other clinical research shows that echinacea may increase the clearance of midazolam, suggesting that echinacea might induce CYP3A4. The discrepancy is thought to be due to differing effects of echinacea on intestinal versus hepatic CYP3A4 enzymes. Echinacea appears to induce hepatic CYP3A4 but inhibit intestinal CYP3A4. In some cases, these effects might cancel each other out, but in others, drug levels may be increased or decreased depending on the level of effect at hepatic and intestinal sites. The effect of echinacea on CYP3A4 activity may differ depending on the CYP3A4 substrate.

Likelihood Possible Evidence B
Etoposide (Vepesid)

Echinacea may increase levels of etoposide.
In one report, concomitant use of etoposide and echinacea was associated with more severe thrombocytopenia than the use of etoposide alone, suggesting inhibition of etoposide metabolism. Etoposide is a cytochrome P450 3A4 (CYP3A4) substrate. Echinacea has variable effects on CYP3A4, but some studies have reported inhibition of the enzyme.

Likelihood Possible Evidence D
Immunosuppressants

Echinacea has immunostimulant activity which may interfere with immunosuppressant therapy.
Theoretically, echinacea may interfere with immunosuppressant therapy because of its immunostimulant activity.

Likelihood Possible Evidence B
Darunavir (Prezista)

Theoretically, echinacea may interfere with the metabolism of darunavir; however, a small clinical study found no effect.
Darunavir is metabolized by cytochrome P450 3A4 (CYP3A4) and is administered with the CYP3A4 inhibitor ritonavir to increase its plasma concentrations. Echinacea has variable effects on CYP3A4, but administration of an E. purpurea root extract (Arkocapsulas Echinacea, Arkopharma) 500 mg four times daily for 14 days did not affect darunavir/ritonavir pharmacokinetics in 15 HIV-infected patients.

Likelihood Unlikely Evidence B
Dayquil Severe

Echinacea is reported to have varying effects on a number of Cytochrome P450 metabolizing enzymes in the liver, including CYP1A2 and CYP3A4, which play a role in acetaminophen and dextromethorphan metabolism (both contained in DayQuil Severe), respectively. Studies have reported both enzyme inhibition and induction, making it difficult to predict clinically significant drug interactions with reliability. Specific drug interaction studies reporting definitive results are rare, and potential drug interactions involving echinacea should likely be taken on a case-by-case basis. Based on what we know about how acetaminophen and dextromethorphan are metabolized, the risk of a clinically significant interaction between echinacea and DayQuil Severe is low.

Likelihood Unlikely Evidence A
Docetaxel (Taxotere)

Theoretically, echinacea may interfere with the metabolism of docetaxel; however, a small clinical study found no effect.
Docetaxel is metabolized by cytochrome P450 3A4 (CYP3A4). Echinacea has variable effects on CYP3A4, but taking E. purpurea whole plant extract (Echinaforce, A. Vogel Biopharma AG) 20 drops three times daily for 2 weeks did not alter the pharmacokinetics of docetaxel in one clinical study.

Likelihood Unlikely Evidence B
Etravirine (Intelence)

Theoretically, echinacea may interfere with the metabolism of etravirine; however, a small clinical study found no effect.
Etravirine is metabolized by cytochrome P450 3A4 (CYP3A4). Echinacea has variable effects on CYP3A4, but taking E. purpurea root extract (Arkocapsulas Echinacea, Arkopharma) 500 mg three times daily for 14 days did not alter the pharmacokinetics of etravirine in HIV-infected patients.

Likelihood Unlikely Evidence B
Lopinavir/Ritonavir (Kaletra)

Theoretically, echinacea may interfere with the metabolism of lopinavir; however, a small clinical study found no effect.
Lopinavir is metabolized by cytochrome P450 3A4 (CYP3A4) and is administered with the CYP3A4 inhibitor ritonavir to increase its plasma concentrations. Echinacea has variable effects on CYP3A4, but taking E. purpurea (Echinamide, Natural Factors Nutritional Products, Inc.) 500 mg three times daily for 14 days did not alter the pharmacokinetics of lopinavir/ritonavir in healthy volunteers.

Likelihood Unlikely Evidence B
Midazolam (Versed)

Theoretically, echinacea may increase the metabolism of intravenous midazolam.
Echinacea induces hepatic CYP3A4 and might decrease plasma levels of midazolam by about 20%, reducing the effectiveness of intravenous midazolam. Echinacea also appears to inhibit intestinal CYP3A4, which could theoretically increase the bioavailability of oral midazolam. This may cancel out the decrease in availability caused by induction of hepatic CYP3A4, such that overall plasma levels after oral administration of midazolam are not affected by echinacea.

Likelihood Possible Evidence B
Warfarin (Coumadin)

Echinacea seems to increase the clearance of warfarin, although the effect may not be clinically significant.
Preliminary clinical research in healthy male volunteers suggests that taking echinacea increases the clearance of the active S-isomer of warfarin after a single dose of warfarin, but there was not a clinically significant effect on the INR.

Likelihood Possible Evidence B
Echinacea full monograph & interactions

Stinging Nettle4 drug types · 164 drugs

Antidiabetes Drugs

Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Clinical research shows that stinging nettle might decrease blood glucose levels in patients with diabetes.

Likelihood Possible Evidence B
Diuretic Drugs

Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Animal research suggests that the above ground parts and roots of stinging nettle may have a diuretic effect.

Likelihood Possible Evidence D
Lithium

Theoretically, stinging nettle might reduce excretion and increase levels of lithium.
Animal research suggests that stinging nettle has diuretic and natriuretic properties, which could alter the excretion of lithium. The dose of lithium might need to be decreased.

Likelihood Possible Evidence D
Warfarin (Coumadin)

There is some concern that stinging nettle might decrease the effects of anticoagulant drugs such as warfarin.
Stinging nettle contains a significant amount of vitamin K. When taken in large quantities, this might interfere with the activity of warfarin.

Likelihood Possible Evidence D
Stinging Nettle full monograph & interactions

Bromelain2 drug types · 141 drugs

Anticoagulant/Antiplatelet Drugs

Bromelain may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
There is one case report of a patient experiencing minor bruising while taking bromelain with naproxen. Bromelain is thought to have antiplatelet activity. Whether this interaction is of concern with topical bromelain is unclear. Interference with coagulation of burn wounds has been reported in a patient receiving bromelain-based enzymatic debridement. However, observational research has found that topical bromelain debridement is not associated with increases or decreases in laboratory markers of coagulation when compared with surgical debridement.

Likelihood Possible Evidence D
Tetracycline Antibiotics

Theoretically, bromelain might increase levels of tetracycline antibiotics.
Laboratory research suggests that bromelain might increase the absorption of tetracycline antibiotics. However, a study in healthy adults reported no difference in tetracycline plasma levels when a 500 mg dose was taken with or without bromelain 80 mg.

Likelihood Possible Evidence B
Bromelain full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Seasonal Clear, from the product label.

Priority One Nutritional Supplements

See all Priority One Nutritional Supplements products
Name
Priority One Nutritional Supplements, Inc.
Web Address
www.priorityonevitamins.com
Pharmacist Counseling Corner

Seasonal Clear by Priority One Nutritional Supplements: Common Questions

Does Seasonal Clear by Priority One Nutritional Supplements interact with any medications?
Yes. Based on its ingredients, Seasonal Clear has a known interaction with 1,062 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Seasonal Clear contains 8 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 Seasonal Clear if I'm pregnant?
The safety data isn't there for most of these ingredients. Bromelain and stinging nettle should be avoided in pregnancy. Echinacea and protease are best avoided unless your doctor says otherwise. For the others, there isn't enough data to know either way. Talk with your doctor or pharmacist before you start.
Can I take it while breastfeeding?
Safety while breastfeeding hasn't been established for bromelain, stinging nettle, and echinacea, so those should be avoided. Protease and lipase have little safety data during breastfeeding, so check with your healthcare provider first. There's no data on file for the others.
What are the most common side effects?
Bromelain commonly causes diarrhea, flatulence, and stomach upset. Stinging nettle most often causes constipation or diarrhea. Echinacea can trigger abdominal pain, constipation, diarrhea, nausea, rashes, and stomach upset. All three are generally well tolerated, but digestive upset is the most frequent complaint.
Is there any evidence that this actually works for allergies?
Not really. Bromelain, stinging nettle, and echinacea all have insufficient reliable evidence for hay fever. The evidence just isn't established in the data we hold. You'd want to talk with your doctor about what's actually proven for seasonal allergy relief.
Can I be allergic to these ingredients?
Yes. Bromelain can trigger allergic reactions, especially in people sensitive to pineapple. Echinacea can cause allergic reactions, particularly if you're sensitive to ragweed or related plants like daisies. Protease, lipase, and stinging nettle can all cause allergic reactions too, though serious ones are rare. If you have a history of plant or pollen allergies, flag this with your pharmacist.
Why does this product have digestive enzymes in it?
Bromelain, protease, and lipase are all enzymes that break down proteins and fats. The product pairs them with stinging nettle and echinacea, which are traditionally used during allergy season. There's insufficient evidence that the enzymes help, but the combination is meant to support digestion alongside the herbal support.

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.

Seasonal Clear label
Go deeper

The Full Monographs Behind Seasonal Clear’s Ingredients

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

Herb & supplement monograph

Bromelain

Interacts with 141 drugs

Bromelain is a group of protein-digesting enzymes from pineapple that people take mainly for inflammation, swelling, and sinus problems. Some early studies are promising, but the overall evi...

Read the full Bromelain monograph → Herb & supplement monograph

Proteolytic Enzymes (proteases)

Proteolytic enzymes are proteins that help break down other proteins, and common examples include bromelain (from pineapple), papain (from papaya), trypsin, chymotrypsin, and pancreatin. Peo...

Read the full Proteolytic Enzymes (proteases) monograph → Herb & supplement monograph

Lipase

Lipase is a digestive enzyme that helps your body break down dietary fats. It is well established as part of prescription pancreatic enzyme therapy for people who cannot make enough of their...

Read the full Lipase monograph → Herb & supplement monograph

Stinging Nettle

Interacts with 164 drugs

Stinging nettle is a common plant used as food and in traditional medicine, most often for prostate symptoms, allergies, and joint pain. The evidence is mixed and mostly preliminary, so it i...

Read the full Stinging Nettle monograph → Herb & supplement monograph

Echinacea

Interacts with 816 drugs

Echinacea is a popular herb taken to help prevent or shorten the common cold, but study results are mixed and the overall benefit appears small at best. It is generally well tolerated for sh...

Read the full Echinacea monograph →
Sources

Sources & How We Checked

Seasonal Clear'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 97 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.

Bromelain 19 references
  1. Nettis E, Napoli G, Ferrannini A, Tursi A. IgE-mediated allergy to bromelain. Allergy 2001;56:257-8. PubMed
  2. Taussig SJ, Batkin S. Bromelain, the enzyme complex of pineapple (Ananas comosus) and its clinical application. An update. J Ethnopharmacol 1988;22:191-203.. PubMed
  3. Bradbrook ID, Morrison PJ, Rogers HJ. The effect of bromelain on the absorption of orally administered tetracycline. Br J Clin Pharmacol 1978;6:552-4. PubMed
  4. Bush TM, Rayburn KS, Holloway SW, et al. Adverse interactions between herbal and dietary substances and prescription medications: a clinical survey. Altern Ther Health Med 2007;13:30-5.
  5. Brien S, Lewith G, Walker AF, et al. Bromelain as an adjunctive treatment for moderate-to-severe osteoarthritis of the knee: a randomized placebo-controlled pilot study. QJM 2006;99:841-50. PubMed
  6. Mori S, Ojima Y, Hirose T, et al. The clinical effect of proteolytic enzyme containing bromelain and trypsin on urinary tract infection evaluated by double blind method. Acta Obstet Gynaecol Jpn 1972;19:147-53.
  7. Glaser D, Hilberg T. The influence of bromelain on platelet count and platelet activity in vitro. Platelets 2006;17:37-41. PubMed
  8. Heinicke R M, van der Wal L, Yokoyama M. Effect of bromelain (Ananase) on human platelet aggregation. Experientia 1972;28:844-5. PubMed
  9. Gailhofer, G., Wilders-Truschnig, M., Smolle, J., and Ludvan, M. Asthma caused by bromelain: an occupational allergy. Clin Allergy 1988;18(5):445-450. PubMed
  10. Mattei, O., Fabri, G., and Farina, G. [Occupational health experience regarding four cases of asthma due to bromelain (author's transl)]. Medicina del Lavoro 1979;70(5):404-409.
  11. Galleguillos, F. and Rodriguez, J. C. Asthma caused by bromelin inhalation. Clin Allergy 1978;8(1):21-24. PubMed
  12. Perez-Camo I, Quirce S, Duran MA, and et al. Latex allergy: evidence of cross-reactivity with papain and bromelain [abstract]. Allergy 1996;51(suppl 31):48.
  13. Martin GJ, Ehrenreich J, and Asbell N. Bromelain: pineapple proteases with anti-edema activity. Exp Med Surg 1962;20:227-247.
  14. Kasemsuk T, Saengpetch N, Sibmooh N, Unchern S. Improved WOMAC score following 16-week treatment with bromelain for knee osteoarthritis. Clin Rheumatol. 2016 Oct;35(10):2531-40. PubMed
  15. Kutlu Ö, DemirbaS A, Elmas ÖF, Güvenç U, Metin A. Fixed drug eruption: a new side effect of bromelain. Contact Dermatitis 2020. Online ahead of print. PubMed
  16. Shoham Y, Shapira E, Haik J, et al. Bromelain-based enzymatic debridement of chronic wounds: Results of a multicentre randomized controlled trial. Wound Repair Regen 2021;29(6):899-907. PubMed
  17. Pfister P, Garcia Wendel PD, Kim BS, et al. Coagulation side effects of enzymatic debridement in burned patients. Burns 2022. PubMed
  18. Hasham S, Riyat H, Fletcher A, O'Boyle CP, Alexander S. To bleed or not to bleed? Case series and discussion of haemorrhage risk with enzymatic debridement in burn injuries. Scars Burn Heal 2023;9:20595131231168333. PubMed
  19. Leelakanok N, Petchsomrit A, Janurai T, Saechan C, Sunsandee N. Efficacy and safety of bromelain: A systematic review and meta-analysis. Nutr Health 2023. PubMed

See these in context on the Bromelain monograph →

Proteolytic Enzymes (proteases) 3 references
  1. Weeks JA, Harper RA, Simon RA, Burdick JD. Assessment of sensitization risk of a laundry pre-spotter containing protease. Cutan Ocul Toxicol. 2011;30(4):272-9. PubMed
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Lipase 1 reference
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Stinging Nettle 23 references
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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