Major interaction on record — check this product against your medications before combining. Based on 3 of 4 ingredients. Check your meds →
Dietary supplement

Pollenase Ingredients & Drug Interactions

by Ecological Formulas

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

First and foremost: checking Pollenase 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: Major

Pollenase is a dietary supplement by Ecological Formulas with 4 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 553 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are N-Acetyl-L-Cysteine, Ascorbyl Palmitate, Nettle (leaf) Powder. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Pollenase by Ecological Formulas

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

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HelloPharmacist Scorecard of Pollenase by Ecological Formulas

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

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Sep 3, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 4 of its 4 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Pollenase contains four active ingredients. Ascorbyl palmitate and vitamin C are forms of vitamin C, an antioxidant nutrient.

N-acetyl cysteine (NAC) is an amino acid derivative that supports respiratory and immune function. Nettle leaf powder is a traditional herbal ingredient.

The capsule shell and other inactive ingredients include gelatin, cellulose, and silicon dioxide.

Does it work?

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

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Acetaminophen poisoning — rated "Effective" (N-acetyl Cysteine (nac)) (Natural Medicines).
  • On file: Atelectasis — rated "Effective" (N-acetyl Cysteine (nac)) (Natural Medicines).
  • On file: Tracheostomy care — rated "Effective" (N-acetyl Cysteine (nac)) (Natural Medicines).
  • On file: Vitamin C deficiency — rated "Effective" (Vitamin C) (Natural Medicines).
  • On file: Bronchial diagnostic studies — rated "Effective" (N-acetyl Cysteine (nac)) (Natural Medicines).

The evidence for this product's active ingredients varies by intended use. Vitamin C is effective for vitamin C deficiency and has some research support as possibly effective for anemia, heart rhythm issues (atrial fibrillation), cataracts, and preventing colds in people who exercise heavily.

N-acetyl cysteine is effective for acetaminophen overdose and certain respiratory conditions, and is possibly effective for bronchitis. Nettle leaf is possibly effective for diabetes management, but the evidence for allergic rhinitis (hay fever), anemia, asthma, prostate health, and gum disease is not yet established in our data.

The evidence, ingredient by ingredient Vitamin C N-acetyl Cysteine (nac) Stinging Nettle

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

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

Why this rating?
  • We hold adverse-effect (side-effect) data for 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Vitamin C is generally well tolerated at normal dietary and supplement doses; very high doses can cause abdominal cramps, heartburn, diarrhea, nausea, and in susceptible people, kidney stones (side effects become more likely above 2 grams daily). N-acetyl cysteine is generally well tolerated at typical doses, with the most common side effects being diarrhea, dry mouth, heartburn, nausea, and vomiting.

Nettle leaf is generally well tolerated for most adults but causes constipation or diarrhea in some. During pregnancy, vitamin C at normal amounts is likely safe, but high-dose supplements should be avoided unless your doctor advises otherwise.

N-acetyl cysteine safety in pregnancy is possibly safe but not well studied; discuss it with your doctor. Nettle is considered likely unsafe in pregnancy due to traditional concerns about effects on the uterus, so avoid it unless your doctor directs otherwise.

Breastfeeding safety data is not established for nettle.

Side effects, ingredient by ingredient Vitamin C N-acetyl Cysteine (nac) Stinging Nettle

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 3 of the 3 matched ingredients can interact with medications — Stinging Nettle, Vitamin C, N-acetyl Cysteine (nac).
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; cancer treatments; diabetes medications; lithium.
  • For scale: 553 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 your doctor or pharmacist before using this product if you take nitroglycerin patches or injections (Major risk), blood pressure medications, anticoagulants or antiplatelet drugs, oral contraceptives or hormone replacement therapy, warfarin, chemotherapy drugs, levothyroxine, diabetes medications, diuretics, lithium, or chloroquine. These are the medication types most likely to be affected.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with strong clinical evidence behind its ingredients' uses. Major medication interactions have been identified, and safety information is well characterized.

Pollenase may be worth considering if you're looking for immune or respiratory support, but it's not right for everyone. If you take any prescription medications—especially blood pressure drugs, blood thinners, heart medications, chemotherapy, thyroid hormone, diabetes or epilepsy drugs, or lithium—check your exact medications with your doctor or pharmacist before starting.

Pregnant or breastfeeding? Talk it over with your healthcare provider first.

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

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

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

At a glance

General information

Key facts about Pollenase, straight from the product label.

Brand Ecological Formulas
Net contents 50 Capsule(s)
Market status On market
Date entered into DSLD Jun 25, 2013
DSLD ID 22903
Product type Other Combinations
Supplement form Capsule
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 Pollenase by Ecological Formulas, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
50
IngredientAmount% DV
Ascorbyl Palmitate30 mg--
N-Acetyl-L-Cysteine100 mg--
Vitamin C12 mg20%
Nettle (leaf) Powder200 mg--

Other ingredients: Gelatin, Cellulose, Silicon Dioxide

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.
General

10090069

FDA Statement of Identity

Dietary Supplement

A DIETARY SUPPLEMENT

Suggested/Recommended/Usage/Directions

DIRECTIONS Take one or two capsules daily, or as directed by a physician.

General Statements

POLLENASE is a scientifically-designed dietary supplement.

EXP0913

Formulation

This product is free of corn, soy, wheat, yeast and other common allergens.

FDA Disclaimer Statement

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

Seals/Symbols

ECOLOGICAL FORMULAS

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

See for yourself

Pollenase by Ecological Formulas label

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

Pollenase 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 Pollenase by Ecological Formulas

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

Serving size1 Capsule(s) Dosage formCapsule Servings per container50 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.

Ascorbyl Palmitate

Interacts with
207 drugs
30 mg per serving

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...

Ascorbyl Palmitate monograph & interactions

N-Acetyl-L-Cysteine

Interacts with
294 drugs
100 mg per serving

N-acetyl cysteine (NAC) is a supplement form of the amino acid cysteine and a building block for the antioxidant glutathione. It has well-established...

N-Acetyl-L-Cysteine monograph & interactions

Vitamin C

Interacts with
207 drugs
12 mg per serving Form: Ascorbyl Palmitate

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...

Vitamin C monograph & interactions

Nettle (leaf) Powder

Interacts with
164 drugs
200 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...

Nettle (leaf) Powder monograph & interactions

Other (inactive) ingredients: Gelatin, Cellulose, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

Pollenase by Ecological Formulas Drug Interactions

Want to check YOUR meds against Pollenase?

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
553Drugs
1 Major 482 Moderate 70 Minor

Ingredients driving the most interactions

N-Acetyl-L-Cysteine 294
Ascorbyl Palmitate 207
Nettle (leaf) Powder 164

Individual Drug Interactions

The ingredients in Pollenase interact with 553 drugs. Click any drug to see the details.

3 of the 4 ingredients in Pollenase interact with drugs. Each result below shows which ingredient is responsible. N-Acetyl-L-Cysteine Ascorbyl Palmitate Nettle (leaf) Powder

Each ingredient & the kinds of drugs it affects

For each ingredient in Pollenase 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.

N-Acetyl-L-Cysteine5 drug types · 294 drugs

Nitroglycerin

N-acetyl cysteine can increase the risk for hypotension and headaches when taken with intravenous or transdermal nitroglycerin.
Clinical research shows that concomitant administration of N-acetyl cysteine and intravenous or transdermal nitroglycerin can cause severe hypotension and intolerable headaches. Furthermore, in vitro research suggests that N-acetyl cysteine increases the anticoagulant activity of nitroglycerin.

Likelihood Probable Evidence B
Activated Charcoal

N-acetyl cysteine might reduce the effects of activated charcoal, while activated charcoal might reduce the absorption of N-acetyl cysteine.
N-acetyl cysteine appears to reduce the capacity of activated charcoal to adsorb acetaminophen and salicylic acid. Conversely, although clinical research suggests that although activated charcoal can reduce the absorption of N-acetyl cysteine by up to 40%, it does not seem to reduce its clinical effects. Other clinical evidence suggests that activated charcoal does not affect the absorption of N-acetyl cysteine.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, N-acetyl cysteine might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
Clinical research suggests that intravenous N-acetyl cysteine decreases prothrombin time, prolongs coagulation time, decreases platelet aggregation, and increases blood loss in surgical patients. Furthermore, in vitro research suggests that N-acetyl cysteine increases the anticoagulant activity of nitroglycerin.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, N-acetyl cysteine might increase the risk of hypotension when taken with antihypertensive drugs.
Animal research suggests that N-acetyl cysteine potentiates the hypotensive effects of the angiotensin-converting enzyme inhibitors (ACEIs) captopril and enalaprilat. Theoretically, combining N-acetyl cysteine with other antihypertensive drugs might increase the risk of hypotension.

Likelihood Possible Evidence D
Chloroquine (Aralen)

Theoretically, N-acetyl cysteine might interfere with the antimalarial effects of chloroquine.
Animal research suggests that N-acetyl cysteine might reduce the antimalarial effects of chloroquine by increasing cellular levels of glutathione.

Likelihood Possible Evidence D
N-Acetyl-L-Cysteine full monograph & interactions

Ascorbyl Palmitate13 drug types · 207 drugs

Alkylating Agents

Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Aluminum

Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.

Likelihood Probable Evidence B
Antitumor Antibiotics

Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Estrogens

Vitamin C might increase blood levels of estrogens.
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products. It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall. When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements. Monitor these patients for estrogen-related side effects.

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

Theoretically, vitamin C might decrease levels of fluphenazine.
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started. The mechanism is not known, and there is no further data to confirm this interaction.

Likelihood Possible Evidence D
Indinavir (Crixivan)

Vitamin C can modestly reduce indinavir levels.
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Vitamin C can increase levothyroxine absorption.
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH.

Likelihood Probable Evidence B
Warfarin (Coumadin)

High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

High-dose vitamin C might slightly prolong the clearance of acetaminophen.
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases. This effect is not likely to be clinically significant.

Likelihood Probable Evidence B
Aspirin

Acidification of the urine by vitamin C might increase aspirin levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Niacin

Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease. It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.

Likelihood Possible Evidence A
Salsalate (Disalcid)

Acidification of the urine by vitamin C might increase salsalate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Ascorbyl Palmitate full monograph & interactions

Nettle (leaf) Powder4 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
Nettle (leaf) Powder full monograph & interactions
The maker

Brand information

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

Ecological Formulas

See all Ecological Formulas products
Name
ECOLOGICAL FORMULAS
Street Address
1061-B SHARY PLACE
City
CONCORD
State
CA
ZipCode
94518
Pharmacist Counseling Corner

Pollenase by Ecological Formulas: Common Questions

Does Pollenase by Ecological Formulas interact with any medications?
Yes. Based on its ingredients, Pollenase has a known interaction with 553 medications, including 1 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Pollenase contains 4 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take Pollenase with my blood thinner?
Both vitamin C and nettle leaf in this product may reduce warfarin's effectiveness, and N-acetyl cysteine may increase bleeding risk with anticoagulants or antiplatelet drugs. Don't start Pollenase without confirming it's okay with your doctor or pharmacist—they'll know your exact medication and can advise you.
Is this safe to take while I'm pregnant?
Vitamin C at normal amounts is likely safe in pregnancy, but N-acetyl cysteine hasn't been well studied for pregnancy safety. Nettle is considered likely unsafe in pregnancy due to traditional concerns about effects on the uterus. Talk with your doctor before taking this product while pregnant.
What's N-acetyl cysteine for, and are there side effects?
N-acetyl cysteine supports respiratory and immune health. At typical doses it's generally well tolerated, but it can cause diarrhea, dry mouth, heartburn, nausea, and vomiting in some people. Side effects are more common at doses above 30 grams daily.
Will high doses of this product cause problems?
Vitamin C at very high doses can cause abdominal cramps, heartburn, diarrhea, nausea, and kidney stones in people prone to them—side effects are more likely above 2 grams daily. N-acetyl cysteine side effects also increase at very high doses (above 9 grams single dose or 30 grams daily). Stick to the label dose.
Does this help with allergies or hay fever?
Nettle leaf is sometimes used for allergies, but our data shows the evidence for allergic rhinitis (hay fever) isn't yet established as reliable. You might try it, but don't count on it as your only allergy support—talk to your doctor about what's proven for your situation.
Can I take this while breastfeeding?
Safety data during breastfeeding is not established for nettle leaf, so it's best avoided unless your doctor advises otherwise. Vitamin C and N-acetyl cysteine don't have a breastfeeding safety rating on file, so discuss this product with your healthcare provider if you're nursing.

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.

Pollenase label
Go deeper

The Full Monographs Behind Pollenase’s Ingredients

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

Herb & supplement monograph

Vitamin C

Interacts with 207 drugs

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for immune function, collagen, and acts as an...

Read the full Vitamin C monograph → Herb & supplement monograph

N-acetyl Cysteine (nac)

Interacts with 294 drugs

N-acetyl cysteine (NAC) is a supplement form of the amino acid cysteine and a building block for the antioxidant glutathione. It has well-established prescription uses for acetaminophen over...

Read the full N-acetyl Cysteine (nac) 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 →
Sources

Sources & How We Checked

Pollenase'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 160 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Vitamin C 51 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Back DJ, Breckenridge AM, MacIver M, et al. Interaction of ethinyloestradiol with ascorbic acid in man. Br Med J (Clin Res Ed) 1981;282:1516.
  3. Morris JC, Beeley L, Ballantine N. Interaction of ethinyloestradiol with ascorbic acid in man [letter]. Br Med J (Clin Res Ed) 1981;283:503.
  4. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  5. Dwyer JH, Merz NB, Shirocre AM, et al. Progression of early atherosclerosis and intake of vitamin C and vitamin E from supplements and food. The Los Angeles Atherosclerosis Study. 41st Annual Conference on Cardiovascular Disease Epidemiology and Prevent
  6. Levine M, Rumsey SC, Daruwala R, et al. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415-23. PubMed
  7. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  8. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  9. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Press, 2000. Available at: http://www.nap.edu/books/0309069351/html/.
  10. Houston JB, Levy G. Drug biotransformation interactions in man VI: Acetaminophen and ascorbic acid. J Pharm Sci 1976;65:1218-21. PubMed
  11. Brown BG, Zhao XQ, Chait A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med 2001;345:1583-93. DOI
  12. Rosenthal G. Interaction of ascorbic acid and warfarin. JAMA 1971;215:1671. DOI
  13. Hume R, Johnstone JM, Weyers E. Interaction of ascorbic acid and warfarin. JAMA 1972;219:1479. DOI
  14. Smith EC, Skalski RJ, Johnson GC, Rossi GV. Interaction of ascorbic acid and warfarin. JAMA 1972;221:1166. DOI
  15. Traxer O, Huet B, Poindexter J, et al. Effect of ascorbic acid consumption on urinary stone risk factors. J Urol 2003;170:397-401.. PubMed
  16. Domingo JL, Gomez M, Llobet JM, Richart C. Effect of ascorbic acid on gastrointestinal aluminum absorption (letter). Lancet 1991;338:1467.
  17. Domingo JL, Gomez M, Llobet JM, Corbella J. Influence of some dietary constituents on aluminum absorption and retention in rats. Kidney Int 1991;39:598-601. PubMed
  18. Partridge NA, Regnier FE, White JL, Hem SL. Influence of dietary constituents on intestinal absorption of aluminum. Kidney Int 1989;35:1413-7. PubMed
  19. Mc Leod DC, Nahata MC. Inefficacy of ascorbic acid as a urinary acidifier (letter). N Engl J Med 1977;296:1413. DOI
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  17. Oliver, F., Amon, E. U., Breathnach, A., Francis, D. M., Sarathchandra, P., Black, A. K., and Greaves, M. W. Contact urticaria due to the common stinging nettle (Urtica dioica)-- histological, ultrastructural and pharmacological studies. Clin Exp Dermato PubMed
  18. Kulze, A. and Greaves, M. Contact urticaria caused by stinging nettles. Br.J Dermatol. 1988;119(2):269-270. PubMed
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  20. Maor D, Little M. Skin contact with a stinging tree requiring intensive care unit admission. Contact Dermatitis. 2017 Nov;77(5):335-37. PubMed
  21. Easton L, Vaid S, Nagel AK, Venci JV, Fortuna RJ. Stinging Nettle (Urtica dioica): An Unusual Case of Galactorrhea. Am J Case Rep 2021;22:e933999. PubMed
  22. Niazi B, Ahmed K, Ahmed M, Ali S, Song K, Elias S. Drug-Induced Liver Injury from Herbal Liver Detoxification Tea. Case Rep Gastroenterol 2022;16(3):612-617. PubMed
  23. Nnamani I, Tolu-Akinnawo O, Dufera RR, Akintunde A, Maliakkal B. Tinospora cordifolia (Guduchi/Giloy)-Induced Liver Injury: A Case Review. Cureus 2023;15(5):e39793. PubMed

See these in context on the Stinging Nettle monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

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

© 2021 Therapeutic Research Center, LLC

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