Interactions on record — worth a quick check against your medications. Based on 7 of 8 ingredients. Check your meds →
Dietary supplement

Let's Breathe! Kids Ingredients & Drug Interactions

by Soria Natural

Let's Breathe! Kids label
See full label image
Liquid Category: Botanical With Nutrients
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 Let's Breathe! Kids 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

Let's Breathe! Kids is a dietary supplement by Soria Natural with 8 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 2,170 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are dried Marshmallow extract, Propolis extract, Eucalyptus extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Let's Breathe! Kids by Soria Natural

Ask about any prescription or over-the-counter medication and we check it for interactions with Let's Breathe! Kids by Soria Natural — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Let's Breathe! Kids by Soria Natural

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

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 13, 2026

What’s inside

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.

Let's Breathe! Kids contains 8 active ingredients.

Vitamin C supports immune function and is used for deficiency prevention. Peppermint extract may help with digestion and comfort.

Thyme extract, eucalyptus extract, and dried marshmallow extract are traditionally used to support respiratory comfort. Sundew extract and propolis extract round out the blend with traditional herbal support.

European Elder extract is also included. The liquid also contains inactive ingredients including fruit concentrate, water, glycerin, microcrystalline cellulose, sodium carboxymethylcellulose, natural lemon flavor, citric acid, potassium sorbate, steviol glycosides, and copper sulfate.

Does it work?

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

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

Why this rating?
  • The label markets this product for: all-natural herbal blend to support clear airways.
  • We looked for evidence on: Cough, Acute bronchitis, Bronchitis, Common cold, Asthma, Congestion — and 2 related terms.
  • The closest evidence on file: Vitamin C is rated "Possibly Ineffective" for Acute bronchitis (Natural Medicines).
  • Also on file: Propolis is rated "Insufficient Reliable Evidence To Rate" for Common cold.
  • Also on file: Eucalyptus is rated "Insufficient Reliable Evidence To Rate" for Bronchitis, Asthma, Cough.

For vitamin C, the evidence shows it's effective for vitamin C deficiency and possibly effective for anemia of chronic disease, atrial fibrillation, cataracts, and exercise-induced respiratory infections. Peppermint extract is likely effective for irritable bowel syndrome and possibly effective for indigestion, chemotherapy-related nausea, and colonic spasm relief.

For the other ingredients, the evidence in our data is insufficient to rate their effectiveness: thyme extract, eucalyptus extract, sundew extract, marshmallow extract, and propolis extract all lack reliable evidence for their stated respiratory or health purposes. Propolis is possibly effective for oral mouth sores and cold sores, and possibly effective for diabetes support.

The evidence, ingredient by ingredient Vitamin C Peppermint Thyme Eucalyptus Sundew Propolis Marshmallow

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 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.

Vitamin C is generally well tolerated at normal dietary and supplement doses; however, very high doses can cause stomach cramping, heartburn, nausea, diarrhea, and in rare cases kidney stones (especially in those prone to them). The safety note advises against high-dose supplements during pregnancy unless directed by a healthcare provider.

Peppermint extract is likely safe during pregnancy and lactation when used in food amounts; concentrated oils should be avoided unless approved by your doctor. Adverse effects from peppermint are uncommon but may include stomach pain, anal burning, belching, diarrhea, dry mouth, heartburn, nausea, or vomiting.

Thyme extract is likely safe during pregnancy and lactation in food amounts; medicinal doses lack sufficient safety data. Eucalyptus extract is likely safe during pregnancy and lactation but should not be taken internally, and the undiluted oil can be toxic.

Sundew extract and propolis extract both lack enough safety information and should be avoided during pregnancy and breastfeeding. Marshmallow extract also lacks sufficient safety data during pregnancy and breastfeeding.

Side effects, ingredient by ingredient Vitamin C Peppermint Thyme Eucalyptus Sundew Propolis Marshmallow

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?
  • 6 of the 7 matched ingredients can interact with medications — Propolis, Eucalyptus, Peppermint, Marshmallow, Thyme, among others.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; cancer treatments; diabetes medications; lithium.
  • For scale: 2,171 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.

If your child takes blood thinners (anticoagulants) like warfarin or antiplatelet drugs, discuss this product first with your doctor—vitamin C at high doses and propolis may interfere with them. If your child is on hormonal birth control or hormone replacement therapy, estrogen levels could increase.

Thyroid medication (levothyroxine) absorption may change. If your child takes diabetes medications, eucalyptus theoretically increases low blood sugar risk.

Liver enzyme-metabolized drugs (including some antihistamines, heart medications, and anti-anxiety medications) could be affected by peppermint, eucalyptus, and propolis. Lithium levels could theoretically rise due to marshmallow's possible diuretic effects.

Check your own medication Run your meds through the checker above

The bottom line

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

This product is a multi-ingredient respiratory support blend best suited for parents looking for traditional herbal options for their children. Because it contains vitamin C and several herbs that interact with medications and are metabolized by the liver, anyone taking prescription drugs—especially blood thinners, hormonal birth control, diabetes medications, thyroid drugs, or antipsychotics—should review their medication list with their pharmacist or doctor before starting.

Talk with your child's doctor or pharmacist about whether this product is right for your family.

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 Jul 27, 2021.

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 Let's Breathe! Kids, straight from the product label.

Brand Soria Natural
Barcode (UPC) 8422947316020
Net contents 5 Fluid Ounce(s); 150 mL
Market status On market
Date entered into DSLD Jul 27, 2021
DSLD ID 250760
Product type Botanical With Nutrients
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Children 4 or More Years of Age, Vegan, Vegetarian, Dairy Free, Children more than 1 but less than 4
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 Let's Breathe! Kids by Soria Natural, 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:
2.5 mL, 10 mL
Maximum serving Sizes:
2.5 mL, 10 mL
Servings per container
15
UPC/BARCODE
8422947316020
IngredientAmount% DV
Calories5 Calorie(s), 20 Calorie(s)--
Total Carbohydrates1 Gram(s), 5 Gram(s)1%, 2%
Vitamin C5 mg, 20 mg33%, 22%
Added Sugars1 Gram(s), 3 Gram(s)6%
Total Sugars1 Gram(s), 4 Gram(s)--
Peppermint extract83 mg, 333 mg--
European Elder extract457 mg, 1829 mg--
Thyme extract83 mg, 333 mg--
Eucalyptus extract83 mg, 333 mg--
Sundew extract83 mg, 333 mg--
Propolis extract83 mg, 333 mg--
dried Marshmallow extract77 mg, 307 mg--

Other ingredients: Fruit concentrate, Water, Glycerin, Microcrystalline Cellulose, Sodium Carboxymethylcellulose, natural Lemon flavor, Citric Acid, Potassium Sorbate, Steviol Glycosides, Copper Sulfate

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 Statements

Efficacy and quality

Dosage spoon included.

Formulation

All-natural herbal blend to support and promote clear airways

Made in Spain

Maintains healthy lung function Promotes clear airways

Dairy Free GMO Free

Vegan

Formula

For ages 1+

All-natural herbal blend specially formulated for kids that combines the ancient properties of elder, thyme, eucalyptus, sundew, peppermint and propolis to support healthy breathing.

FDA Statement of Identity

Liquid Dietary Supplement

Precautions

To report serious adverse event, contact 1-866-641-5222.

Child safety cap.

Keep out of reach of children.

Do not use as a substitute for a well-balanced diet and a healthy lifestyle. Do not exceed the recommended serving.

Suggested/Recommended/Usage/Directions

Directions of Use: Shake well before use.

Use product within 60 days of opening. Children 8-12 years: take 2 tsp (10 ml) 3 times daily. Children 4-7 years: take 1 tsp (5 ml) 3 times daily. Children 1-3 years: take 1/2 tsp (2.5) 3 times daily.

Storage

Important: Must be refrigerated after opening to maintain freshness.

Store in a cool and dry place.

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, 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

Let's Breathe! Kids by Soria Natural label

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

Let's Breathe! Kids 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 Let's Breathe! Kids by Soria Natural

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

Serving size2.5 mL Dosage formLiquid Servings per container15 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Vitamin C

Interacts with
207 drugs
5 mg per serving Form: Ascorbic Acid

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

Vitamin C monograph & interactions

Peppermint extract

Interacts with
796 drugs
83 mg per serving

Peppermint is a popular herb with the best evidence supporting enteric-coated peppermint oil for easing IBS symptoms. It is generally well tolerated f...

Peppermint extract monograph & interactions

European Elder extract

457 mg per serving

Thyme extract

Interacts with
379 drugs
83 mg per serving

Thyme is a common kitchen herb that has long been used for coughs, sore throats, and digestive complaints. It is generally safe in the amounts found i...

Thyme extract monograph & interactions

Eucalyptus extract

Interacts with
878 drugs
83 mg per serving

Eucalyptus is best known for its strong-smelling oil used in vapor rubs, inhalants, and lozenges to ease coughs and congestion. It may provide mild, s...

Eucalyptus extract monograph & interactions

Sundew extract

No known
interactions
83 mg per serving

Sundew is a small carnivorous plant used traditionally as a cough and respiratory remedy, often in combination cough syrups and homeopathic products....

Sundew extract monograph & interactions

Propolis extract

Interacts with
921 drugs
83 mg per serving

Propolis is a natural, resin-like substance made by bees that has antimicrobial and anti-inflammatory properties in lab studies. Early research sugges...

Propolis extract monograph & interactions

Dried Marshmallow extract

Interacts with
2,040 drugs
77 mg per serving

Marshmallow root is a traditional herb rich in soothing, gel-like fibers called mucilage, which is why it has long been used for coughs, sore throats,...

Dried Marshmallow extract monograph & interactions

Other (inactive) ingredients: Fruit concentrate, Water, Glycerin, Microcrystalline Cellulose, Sodium Carboxymethylcellulose, Natural Lemon flavor, Citric Acid, Potassium Sorbate, Steviol Glycosides, Copper Sulfate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Let's Breathe! Kids by Soria Natural Drug Interactions

Want to check YOUR meds against Let's Breathe! Kids?

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
2,170Drugs
1,155 Moderate 1,015 Minor

Ingredients driving the most interactions

dried Marshmallow extract 2,040
Propolis extract 921
Eucalyptus extract 878
Peppermint extract 796
Thyme extract 379

Individual Drug Interactions

The ingredients in Let's Breathe! Kids interact with 2,170 drugs. Click any drug to see the details.

6 of the 8 ingredients in Let's Breathe! Kids interact with drugs. Each result below shows which ingredient is responsible. dried Marshmallow extract Propolis extract Eucalyptus extract Peppermint extract Thyme extract Vitamin C

Each ingredient & the kinds of drugs it affects

For each ingredient in Let's Breathe! Kids 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.

dried Marshmallow extract3 drug types · 2,040 drugs

Lithium

Theoretically, due to potential diuretic effects, marshmallow might reduce excretion and increase levels of lithium.
Marshmallow is thought to have diuretic properties. To avoid lithium toxicity, the dose of lithium might need to be decreased when used with marshmallow.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, marshmallow flower might have antiplatelet effects.
Animal research suggests that marshmallow flower extract has antiplatelet effects. However, the root and leaf of marshmallow, not the flower, are the plant parts most commonly found in dietary supplements. Theoretically, use of marshmallow flower with anticoagulant/antiplatelet drugs can have additive effects, and might increase the risk for bleeding in some patients.

Likelihood Unlikely Evidence D
Oral Drugs

Theoretically, mucilage in marshmallow might impair absorption of oral drugs.
Marshmallow contains mucilage which can affect oral drug absorption. To avoid changes in absorption, take marshmallow 30-60 minutes after oral medications.

Likelihood Possible Evidence D
dried Marshmallow extract full monograph & interactions

Propolis extract8 drug types · 921 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, propolis might increase the risk of bleeding when taken with antiplatelet or anticoagulant drugs.
In vitro research shows that propolis water extract and the propolis constituent, caffeic acid phenethyl ester, can inhibit platelet aggregation. Additionally, evidence from an animal model shows that taking propolis in addition to warfarin decreases INR, suggesting that propolis can decrease the effectiveness of warfarin.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, high doses of propolis might increase blood levels of drugs metabolized by CYP1A2.
In vitro research shows that propolis extract can inhibit CYP1A2. However, animal research shows that propolis extract does not significantly affect CYP1A2 activity when administered to rats at doses up to 250 mg/kg. It is postulated that the constituents of propolis that inhibit CYP1A2 in vitro do not have significant effects in vivo due to low bioavailability and hepatic first-pass effect. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, high doses of propolis might increase blood levels of drugs metabolized by CYP2C19.
In vitro research shows that propolis extract can inhibit CYP2C19. However, animal research shows that propolis extract does not significantly affect CYP2C19 activity when administered to rats at doses up to 250 mg/kg. It is postulated that the constituents of propolis that inhibit CYP2C19 in vitro do not have significant effects in vivo due to low bioavailability and hepatic first-pass effect. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, high doses of propolis might increase blood levels of drugs metabolized by CYP2C9.
In vitro research shows that propolis extract can inhibit CYP2C9. However, animal research shows that propolis extract does not significantly affect CYP2C9 activity when administered to rats at doses up to 250 mg/kg. It is postulated that the constituents of propolis that inhibit CYP2C9 in vitro do not have significant effects in vivo due to low bioavailability and hepatic first-pass effect. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, high doses of propolis might increase blood levels of drugs metabolized by CYP2D6.
In vitro research shows that propolis extract can inhibit CYP2D6. However, animal research shows that propolis extract does not significantly affect CYP2D6 activity when administered to rats at doses up to 250 mg/kg. It is postulated that the constituents of propolis that inhibit CYP2D6 in vitro do not have significant effects in vivo due to low bioavailability and hepatic first-pass effect. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2E1 (Cyp2E1) Substrates

Theoretically, propolis might increase levels of drugs metabolized by CYP2E1.
In vitro research shows that propolis can inhibit CYP2E1. This effect has not been reported in humans.

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

Theoretically, high doses of propolis might increase blood levels of drugs metabolized by CYP3A4.
Some in vitro research shows that propolis extract can inhibit CYP3A4; however, other in vitro research shows that propolis has no effect on CYP3A4 activity. Furthermore, animal research shows that propolis extract does not significantly affect CYP3A4 activity when administered to rats at doses up to 250 mg/kg. It is postulated that the constituents of propolis that might in inhibit CYP3A4 in vitro do not have significant effects in vivo due to low bioavailability and hepatic first-pass effect. This effect has not been reported in humans.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, propolis might decrease the effectiveness of warfarin.
Animal research shows that taking propolis in addition to warfarin decreases the international normalized ratio (INR). This effect has not been reported in humans.

Likelihood Possible Evidence D
Propolis extract full monograph & interactions

Eucalyptus extract7 drug types · 878 drugs

Amphetamines

Theoretically, inhaling eucalyptol may reduce the effectiveness of amphetamines.
Animal research suggests that inhaling eucalyptol may reduce the levels of amphetamines in the blood.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, eucalyptus leaf might increase the risk of hypoglycemia.
Animal research suggests that eucalyptus leaf might have hypoglycemic activity, and might have additive effects when used with antidiabetes drugs.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, eucalyptus might increase the levels of CYP1A2 substrates.
In vitro research suggests that eucalyptus oil might inhibit CYP1A2, although this has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, eucalyptus might increase the levels of CYP2C19 substrates.
In vitro research suggests that eucalyptus oil might inhibit CYP2C19, although this has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, eucalyptus might increase the levels of CYP2C9 substrates.
In vitro research suggests that eucalyptus oil might inhibit CYP2C9, although this has not been reported in humans.

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

Theoretically, eucalyptus might increase the levels of CYP3A4 substrates.
In vitro research suggests that eucalyptus oil might inhibit CYP3A4, although this has not been reported in humans.

Likelihood Possible Evidence D
Pentobarbital (Nembutal)

Theoretically, inhaling eucalyptol might reduce the effectiveness of pentobarbital.
Animal research suggests that inhaling eucalyptol reduces the level of pentobarbital that reaches the brain.

Likelihood Possible Evidence D
Eucalyptus extract full monograph & interactions

Peppermint extract5 drug types · 796 drugs

Cyclosporine (Neoral, Sandimmune)

Theoretically, peppermint oil might increase the levels and adverse effects of cyclosporine.
In animal research, peppermint oil inhibits cyclosporine metabolism and increases cyclosporine levels. Inhibition of cytochrome P450 3A4 (CYP3A4) may be partially responsible for this interaction. An interaction between peppermint oil and cyclosporine has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, peppermint might increase the levels of CYP2C19 substrates.
In vitro research shows that peppermint oil inhibits CYP2C19. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, peppermint might increase the levels of CYP2C9 substrates.
In vitro research shows that peppermint oil inhibits CYP2C9. So far, this interaction has not been reported in humans.

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

Theoretically, peppermint might increase the levels of CYP3A4 substrates.
Clinical research in healthy volunteers shows that a single dose of peppermint oil 600 mg inhibits CYP3A4 enzymes and increases the AUC of felodipine, a CYP3A4 substrate. However, in vitro research suggests that peppermint oil only inhibits CYP3A4 at very high concentrations.

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

Theoretically, peppermint might increase the levels of CYP1A2 substrates.
In vitro and animal research shows that peppermint oil and peppermint leaf inhibit CYP1A2. However, in clinical research, peppermint tea did not significantly affect the metabolism of caffeine, a CYP1A2 substrate. It is possible that the 6-day duration of treatment may have been too short to identify a difference.

Likelihood Possible Evidence B
Peppermint extract full monograph & interactions

Thyme extract4 drug types · 379 drugs

Anticholinergic Drugs

Theoretically, concurrent use of anticholinergic drugs and thyme essential oil might reduce the effects of anticholinergic drugs.
In vitro evidence suggests that thyme essential oil and specific essential oil constituents like thymohydroquinone and carvacrol can inhibit acetylcholinesterase (AChE). However, this effect has not been observed in humans.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, thyme leaf extract might have additive effects with anticoagulant or antiplatelet drugs.
In vitro and animal research suggests that thyme leaf extract has antiplatelet effects. However, this effect has not been observed in humans.

Likelihood Possible Evidence D
Cholinergic Drugs

Theoretically, concurrent use of cholinergic drugs and thyme essential oil might cause additive cholinergic effects.
In vitro evidence suggests that thyme essential oil and specific essential oil constituents like thymohydroquinone and carvacrol can inhibit acetylcholinesterase (AChE). However, this effect has not been observed in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, thyme might competitively inhibit the effects of estrogen replacement therapy.
In vitro research shows that thyme has estrogen receptor-binding activity and phytoestrogen content. However, this effect has not been observed in humans.

Likelihood Possible Evidence D
Thyme extract full monograph & interactions

Vitamin C13 drug types · 207 drugs

Alkylating Agents

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

Likelihood Possible Evidence D
Aluminum

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

Likelihood Probable Evidence B
Antitumor Antibiotics

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

Likelihood Possible Evidence D
Estrogens

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

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

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

Likelihood Possible Evidence D
Indinavir (Crixivan)

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

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

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

Likelihood Probable Evidence B
Warfarin (Coumadin)

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

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

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

Likelihood Probable Evidence B
Aspirin

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

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

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

Likelihood Possible Evidence B
Niacin

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

Likelihood Possible Evidence A
Salsalate (Disalcid)

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

Likelihood Possible Evidence B
Vitamin C full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Let's Breathe! Kids, from the product label.

Soria Natural

See all Soria Natural products
Name
Naturali LLC.
Street Address
600 Ave.
City
Munoz Rivera
State
San Juan
ZipCode
00918
Phone Number
1-866-641-5222
Pharmacist Counseling Corner

Let's Breathe! Kids by Soria Natural: Common Questions

Does Let's Breathe! Kids by Soria Natural interact with any medications?
Yes. Based on its ingredients, Let's Breathe! Kids has a known interaction with 2,170 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Let's Breathe! Kids 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.
Is this safe for kids?
The product contains ingredients generally well tolerated in small amounts, though several lack robust safety data in children. Vitamin C at normal doses is safe; peppermint, thyme, and eucalyptus extracts are used traditionally in respiratory blends. Talk with your pediatrician before starting to make sure it's right for your child.
What does peppermint extract do in this formula?
Peppermint extract is likely effective for irritable bowel syndrome and may help with indigestion and nausea. Here, it's part of a respiratory support blend and traditionally used to help with comfort and breathing.
Can I give this if my child is on an inhaler or other asthma medication?
You'll need to check with your child's doctor or pharmacist first. Eucalyptus extract in the formula could theoretically affect how the liver processes some medications, and you want to make sure there are no conflicts with their asthma care.
Is there vitamin C from natural sources only?
The product facts don't specify the source of vitamin C or whether it's synthetic or natural. You can contact the manufacturer directly if that matters for your family.
How much vitamin C is in a dose?
The product facts don't list the amount of each ingredient per dose. Check the label on the bottle or contact Soria Natural for the specific quantities.
Can I use this while my child is on antibiotics?
Possibly, but it depends which antibiotic and other factors. Because vitamin C and the plant extracts can affect how the liver processes medications, talk with your pharmacist or doctor to be sure there are no interactions before combining them.

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.

Let's Breathe! Kids label
Go deeper

The Full Monographs Behind Let's Breathe! Kids’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

Peppermint

Interacts with 796 drugs

Peppermint is a popular herb with the best evidence supporting enteric-coated peppermint oil for easing IBS symptoms. It is generally well tolerated for most adults, but it can cause heartbu...

Read the full Peppermint monograph → Herb & supplement monograph

Thyme

Interacts with 379 drugs

Thyme is a common kitchen herb that has long been used for coughs, sore throats, and digestive complaints. It is generally safe in the amounts found in food, and some cough products that com...

Read the full Thyme monograph → Herb & supplement monograph

Eucalyptus

Interacts with 878 drugs

Eucalyptus is best known for its strong-smelling oil used in vapor rubs, inhalants, and lozenges to ease coughs and congestion. It may provide mild, short-term relief of cold symptoms, but t...

Read the full Eucalyptus monograph → Herb & supplement monograph

Sundew

Sundew is a small carnivorous plant used traditionally as a cough and respiratory remedy, often in combination cough syrups and homeopathic products. Modern human evidence for its effectiven...

Read the full Sundew monograph → Herb & supplement monograph

Propolis

Interacts with 921 drugs

Propolis is a natural, resin-like substance made by bees that has antimicrobial and anti-inflammatory properties in lab studies. Early research suggests it may help with cold sores, mouth so...

Read the full Propolis monograph → Herb & supplement monograph

Marshmallow

Interacts with 2,040 drugs

Marshmallow root is a traditional herb rich in soothing, gel-like fibers called mucilage, which is why it has long been used for coughs, sore throats, and stomach irritation. Evidence for th...

Read the full Marshmallow monograph →
Sources

Sources & How We Checked

Let's Breathe! Kids'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
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  3. Morris JC, Beeley L, Ballantine N. Interaction of ethinyloestradiol with ascorbic acid in man [letter]. Br Med J (Clin Res Ed) 1981;283:503.
  4. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  5. Dwyer JH, Merz NB, Shirocre AM, et al. Progression of early atherosclerosis and intake of vitamin C and vitamin E from supplements and food. The Los Angeles Atherosclerosis Study. 41st Annual Conference on Cardiovascular Disease Epidemiology and Prevent
  6. Levine M, Rumsey SC, Daruwala R, et al. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415-23. PubMed
  7. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  8. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  9. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Press, 2000. Available at: http://www.nap.edu/books/0309069351/html/.
  10. Houston JB, Levy G. Drug biotransformation interactions in man VI: Acetaminophen and ascorbic acid. J Pharm Sci 1976;65:1218-21. PubMed
  11. Brown BG, Zhao XQ, Chait A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med 2001;345:1583-93. DOI
  12. Rosenthal G. Interaction of ascorbic acid and warfarin. JAMA 1971;215:1671. DOI
  13. Hume R, Johnstone JM, Weyers E. Interaction of ascorbic acid and warfarin. JAMA 1972;219:1479. DOI
  14. Smith EC, Skalski RJ, Johnson GC, Rossi GV. Interaction of ascorbic acid and warfarin. JAMA 1972;221:1166. DOI
  15. Traxer O, Huet B, Poindexter J, et al. Effect of ascorbic acid consumption on urinary stone risk factors. J Urol 2003;170:397-401.. PubMed
  16. Domingo JL, Gomez M, Llobet JM, Richart C. Effect of ascorbic acid on gastrointestinal aluminum absorption (letter). Lancet 1991;338:1467.
  17. Domingo JL, Gomez M, Llobet JM, Corbella J. Influence of some dietary constituents on aluminum absorption and retention in rats. Kidney Int 1991;39:598-601. PubMed
  18. Partridge NA, Regnier FE, White JL, Hem SL. Influence of dietary constituents on intestinal absorption of aluminum. Kidney Int 1989;35:1413-7. PubMed
  19. Mc Leod DC, Nahata MC. Inefficacy of ascorbic acid as a urinary acidifier (letter). N Engl J Med 1977;296:1413. DOI
  20. Hansten PD, Hayton WL. Effect of antacid and ascorbic acid on serum salicylate concentration. J Clin Pharmacol 1980;20:326-31. PubMed
  21. Dysken MW, Cumming RJ, Channon RA, Davis JM. Drug interaction between ascorbic acid and fluphenazine. JAMA 1979;241:2008. DOI
  22. Vihtamaki T, Parantainen J, Koivisto AM, et al. Oral ascorbic acid increases plasma oestradiol during postmenopausal hormone replacement therapy. Maturitas 2002;42:129-35. PubMed
  23. Slain D, Amsden JR, Khakoo RA, et al. Effect of high-dose vitamin C on the steady-state pharmacokinetics of the protease inhibitor indinavir in healthy volunteers. Pharmacotherapy 2005;25:165-70. PubMed
  24. Cheung MC, Zhao XQ, Chait A, et al. Antioxidant supplements block the response of HDL to simvastatin-niacin therapy in patients with coronary artery disease and low HDL. Arterioscler Thromb Vasc Biol 2001;21:1320-6. PubMed
  25. Feetam CL, Leach RH, Meynell MJ. Lack of a clinically important interaction between warfarin and ascorbic acid. Toxicol Appl Pharmacol 1975;31:544-7. PubMed
  26. Weintraub M, Griner PF. Warfarin and ascorbic acid: lack of evidence for a drug interaction. Toxicol Appl Pharmacol 1974;28:53-6. PubMed
  27. Lee DH, Folsom AR, Harnack L, et al. Does supplemental vitamin C increase cardiovascular disease risk in women with diabetes? Am J Clin Nutr 2004;80:1194-200. PubMed
  28. Taylor EN, Stampfer MJ, Curhan GC. Dietary factors and the risk of incident kidney stones in men: new insights after 14 years of follow-up. J Am Soc Nephrol 2004;15:3225-32. PubMed
  29. Ward NC, Hodgson JM, Croft KD, et al. The combination of vitamin C and grape-seed polyphenols increases blood pressure: a randomized, double-blind, placebo-controlled trial. J Hypertens 2005;23:427-34.. PubMed
  30. Prasad KN. Rationale for using high-dose multiple dietary antioxidants as an adjunct to radiation therapy and chemotherapy. J Nutr 2004;134:3182S-3S. PubMed
  31. Conklin KA. Cancer chemotherapy and antioxidants. J Nutr 2004;134:3201S-3204S. PubMed
  32. Fairweather-Tait S, Hickson K, McGaw B, et al. Orange juice enhances aluminium absorption from antacid preparation. Eur J Clin Nutr. 1994;48(1):71-3.
  33. Gruenwald, J., Graubaum, H. J., Busch, R., and Bentley, C. Safety and tolerance of ester-C compared with regular ascorbic acid. Adv.Ther. 2006;23(1):171-178.
  34. Rahimi, R., Nikfar, S., Rezaie, A., and Abdollahi, M. A meta-analysis on the efficacy and safety of combined vitamin C and E supplementation in preeclamptic women. Hypertens.Pregnancy. 2009;28(4):417-434. PubMed
  35. Einerson, B., Nathorn, C., Kitiyakara, C., Sirada, M., and Thamlikitkul, V. The efficacy of ascorbic acid in suboptimal responsive anemic hemodialysis patients receiving erythropoietin: a meta-analysis. J Med.Assoc.Thai. 2011;94 Suppl 1:S134-S146.
  36. Li, G., Li, L., Yu, C., and Chen, L. Effect of vitamins C and E supplementation on Helicobacter pylori eradication: a meta-analysis. Br.J Nutr 2011;106(11):1632-1637.
  37. Chen X, Shen L, Gu X, et al. High-dose supplementation with vitamin C--induced pediatric urolithiasis: the first case report in a child and literature review. Urology. 2014;84(4):922-4. PubMed
  38. Sattar A, Willman JE, Kolluri R. Possible warfarin resistance due to interaction with ascorbic acid: case report and literature review. Am J Health Syst Pharm. 2013;70(9):782-6. PubMed
  39. Yaich S, Chaabouni Y, Charfeddine K, et al. Secondary oxalosis due to excess vitamin C intake: a cause of graft loss in a renal transplant recipient. Saudi J Kidney Dis Transpl. 2014;25(1):113-6. PubMed
  40. Jalloh MA, Gregory PJ, Hein D, et al. Dietary supplement interactions with antiretrovirals: a systematic review. Int J STD AIDS. 2017 Jan;28(1):4-15. PubMed
  41. Rumbold A, Ota E, Nagata C, Shahrook S, Crowther CA. Vitamin C supplementation in pregnancy. Cochrane Database Syst Rev. 2015;(9):CD004072. PubMed
  42. Seo MS, Kim JK, Shim JY. High-dose vitamin C promotes regression of multiple pulmonary metastases originating from hepatocellular carcinoma. Yonsei Med J. 2015;56(5):1449-52. PubMed
  43. Skelin M, Lucijanic T, Amidzic Klaric D, et al. Factors Affecting Gastrointestinal Absorption of Levothyroxine: A Review. Clin Ther. 2017 Feb;39(2):378-403. PubMed
  44. Jiang K, Tang K, Liu H, Xu H, Ye Z, Chen Z. Ascorbic acid supplements and kidney stones incidence among men and women: a systematic review and meta-analysis. Urol J. 2019;16(2):115-120.
  45. Thomas S, Patel D, Bittel B, et al. Effect of High-Dose Zinc and Ascorbic Acid Supplementation vs Usual Care on Symptom Length and Reduction Among Ambulatory Patients With SARS-CoV-2 Infection: The COVID A to Z Randomized Clinical Trial. JAMA Netw Open. 2 PubMed
  46. Giffen MA, McLemore JL. Hyperoxalosis Secondary to Intravenous Vitamin C Administration as a Non-Allopathic Treatment for Cancer. Acad Forensic Pathol 2019;9(1-2):118-126. PubMed
  47. Maike A, Sturgill D, Gallan A. Oxalate Nephropathy in a Renal Transplant Recipient After Receiving High Dose Ascorbic Acid. Am J Med Sci 2021. PubMed
  48. Shen ZY, Chen YR, Wang MC, Chang SS. High-dose vitamin C-induced acute oxalate nephropathy in a renal transplant recipient: a case report and literature review. Asian J Surg 2022. PubMed
  49. Yanase F, Spano S, Maeda A, et al. Mega-dose sodium ascorbate: a pilot, single-dose, physiological effect, double-blind, randomized, controlled trial. Crit Care 2023;27(1):371. PubMed
  50. Sharma Y, Sumanadasa S, Shahi R, et al. Efficacy and safety of vitamin C supplementation in the treatment of community-acquired pneumonia: a systematic review and meta-analysis with trial sequential analysis. Sci Rep 2024;14(1):11846. PubMed
  51. Pejcic AV, Petrovic NZ, Djordjic MD, Milosavljevic MN. Vitamin C Levels in Pregnant Women and the Efficacy of Vitamin C Supplements in Preventing Premature Rupture of Membranes: A Systematic Review and Meta-Analysis. Balkan Med J 2024;41(4):248-260. PubMed

See these in context on the Vitamin C monograph →

Peppermint 41 references
  1. Liu JH, Chen GH, Yeh HZ, et al. Enteric-coated peppermint-oil capsules in the treatment of irritable bowel syndrome: a prospective, randomized trial. J Gastroenterol 1997;32:765-8. PubMed
  2. Pittler MH, Ernst E. Peppermint oil for irritable bowel syndrome: a critical review and metaanalysis. Am J Gastroenterol 1998;93:1131-5. PubMed
  3. Kline RM, Kline JJ, Di Palma J, Barbero GJ. Enteric-coated, pH-dependent peppermint oil capsules for the treatment of irritable bowel syndrome in children. J Pediatr 2001;138:125-8. PubMed
  4. Madisch A, Heydenreich CJ, Wieland V, et al. Treatment of functional dyspepsia with a fixed peppermint oil and caraway oil combination preparation as compared to cisapride. A multicenter, reference-controlled, double-blind equivalence study. Arzneimittel
  5. May B, Kuntz HD, Kieser M, Kohler S. Efficacy of a fixed peppermint oil/caraway oil combination in non-ulcer dyspepsia. Arzneimittelforschung 1996;46:1149-53.
  6. Micklefield GH, Greving I, May B. Effects of peppermint oil and caraway oil on gastroduodenal motility. Phytother Res 2000;14:20-3. DOI
  7. Morton CA, Garioch J, Todd P, et al. Contact sensitivity to menthol and peppermint in patients with intra-oral symptoms. Contact Dermatitis 1995;32:281-4. PubMed
  8. May B, Kohler S, Schneider B. Efficacy and tolerability of a fixed combination of peppermint oil and caraway oil in patients suffering from functional dyspepsia. Aliment Pharmacol Ther 2000;14:1671-7. PubMed
  9. Nash P, Gould SR, Bernardo DE. Peppermint oil does not relieve the pain of irritable bowel syndrome. Br J Clin Pract 1986;40:292-3. DOI
  10. Rees WD, Evans BK, Rhodes J. Treating irritable bowel syndrome with peppermint oil. Br Med J 1979;2:835-6. PubMed
  11. Davies SJ, Harding LM, Baranowski AP. A novel treatment of postherpetic neuralgia using peppermint oil. Clin J Pain 2002;18:200-2. PubMed
  12. Weston CF. Anal burning and peppermint oil. Postgrad Med J 1987;63:717. PubMed
  13. Dresser GK, Wacher V, Wong S, et al. Evaluation of peppermint oil and ascorbyl palmitate as inhibitors of cytochrome P4503A4 activity in vitro and in vivo. Clin Pharmacol Ther 2002;72:247-55. PubMed
  14. Wacher VJ, Wong S, Wong HT. Peppermint oil enhances cyclosporine oral bioavailability in rats: comparison with D-alpha-tocopheryl poly(ethylene glycol 1000) succinate (TPGS) and ketoconazole. J Pharm Sci 2002;91:77-90.
  15. Lawson MJ, Knight RE, Tran K, et al. Failure of enteric-coated peppermint oil in the irritable bowel syndrome: a randomized double-blind crossover study. J Gastroenterol Hepatol 1988;3:235-8. DOI
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  24. Kalavala, M., Hughes, T. M., Goodwin, R. G., Anstey, A. V., and Stone, N. M. Allergic contact dermatitis to peppermint foot spray. Contact Dermatitis 2007;57(1):57-58. PubMed
  25. Vermaat, H., van Meurs, T., Rustemeyer, T., Bruynzeel, D. P., and Kirtschig, G. Vulval allergic contact dermatitis due to peppermint oil in herbal tea. Contact Dermatitis 2008;58(6):364-365. PubMed
  26. Merat, S., Khalili, S., Mostajabi, P., Ghorbani, A., Ansari, R., and Malekzadeh, R. The effect of enteric-coated, delayed-release peppermint oil on irritable bowel syndrome. Dig.Dis.Sci. 2010;55(5):1385-1390. PubMed
  27. Tran, A., Pratt, M., and DeKoven, J. Acute allergic contact dermatitis of the lips from peppermint oil in a lip balm. Dermatitis 2010;21(2):111-115. DOI
  28. Hitz, Lindenmuller, I and Lambrecht, J. T. Oral care. Curr Probl.Dermatol 2011;40:107-115.
  29. Shavakhi, A., Ardestani, S. K., Taki, M., Goli, M., and Keshteli, A. H. Premedication with peppermint oil capsules in colonoscopy: a double blind placebo-controlled randomized trial study. Acta Gastroenterol Belg 2012;75(3):349-353.
  30. Lech, Y., Olesen, K. M., Hey, H., Rask-Pedersen, E., Vilien, M., and Ostergaard, O. [Treatment of irritable bowel syndrome with peppermint oil. A double- blind study with a placebo]. Ugeskr.Laeger 10-3-1988;150(40):2388-2389.
  31. Parys, B. T. Chemical burns resulting from contact with peppermint oil mar: a case report. Burns Incl.Therm.Inj. 1983;9(5):374-375. PubMed
  32. Bayat R, Borici-Mazi R. A case of anaphylaxis to peppermint. Allergy Asthma Clin Immunol. 2014;10(1):6. PubMed
  33. Rich G, Shah A, Koloski N, et al. A randomized placebo-controlled trial on the effects of Menthacarin, a proprietary peppermint- and caraway-oil-preparation, on symptoms and quality of life in patients with functional dyspepsia. Neurogastroenterol Motil 2 PubMed
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  35. Begas E, Tsioutsiouliti A, Kouvaras E, et al. Effects of peppermint tea consumption on the activities of CYP1A2, CYP2A6, Xanthine Oxidase, N-acetyltranferase-2 and UDP-glucuronosyltransferases-1A1/1A6 in healthy volunteers. Food Chem Toxicol 2017;100:80-9 PubMed
  36. Cash BD, Epstein MS, Shah SM. A Novel Delivery System of Peppermint Oil Is an Effective Therapy for Irritable Bowel Syndrome Symptoms. Dig Dis Sci 2016;61(2):560-71. PubMed
  37. Elsaie LT, El Mohsen AM, Ibrahim IM, Mohey-Eddin MH, Elsaie ML. Effectiveness of topical peppermint oil on symptomatic treatment of chronic pruritus. Clin Cosmet Investig Dermatol 2016;9:333-8. PubMed
  38. Wu J, Xu R, Zhan R, et al. Effective symptomatic treatment for severe and intractable pruritus associated with severe burn-induced hypertrophic scars: A prospective, multicenter, controlled trial. Burns 2016;42(5):1059-66. PubMed
  39. Weerts ZZRM, Masclee AAM, Witteman BJM, et al. Efficacy and safety of peppermint oil in a randomized, double-blind trial of patients with irritable bowel syndrome. Gastroenterology. 2020;158(1):123-136. PubMed
  40. Nee J, Ballou S, Kelley JM, et al. Peppermint Oil Treatment for Irritable Bowel Syndrome: A Randomized Placebo-Controlled Trial. Am J Gastroenterol 2021;116(11):2279-2285. PubMed
  41. Ingrosso MR, Ianiro G, Nee J, et al. Systematic review and meta-analysis: efficacy of peppermint oil in irritable bowel syndrome. Aliment Pharmacol Ther 2022;56(6):932-41. PubMed

See these in context on the Peppermint monograph →

Thyme 18 references
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  2. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
  3. Okazaki K, Kawazoe K, Takaishi Y. Human platelet aggregation inhibitors from thyme (Thymus vulgaris L.). Phytother Res 2002;16:398-9. .
  4. Spiewak R, Skorska C, Dutkiewicz J. Occupational airborne contact dermatitis caused by thyme dust. Contact Dermatitis 2001;44:235-9. . PubMed
  5. Ernst E, Marz R, Sieder C. A controlled multi-centre study of herbal versus synthetic secretolytic drugs for acute bronchitis. Phytomedicine 1997;4:287-93. PubMed
  6. Yamamoto J, Yamada K, Naemura A, et al. Testing various herbs for antithrombotic effect. Nutrition 2005;21(5):580-7. PubMed
  7. 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
  8. Mackiewicz, B., Skorska, C., Dutkiewicz, J., Michnar, M., Milanowski, J., Prazmo, Z., Krysinska-Traczyk, E., and Cisak, E. Allergic alveolitis due to herb dust exposure. Ann Agric Environ Med 1999;6(2):167-170.
  9. Martinez-Gonzalez, M. C., Goday Bujan, J. J., Martinez, Gomez W., and Fonseca, Capdevila E. Concomitant allergic contact dermatitis due to Rosmarinus officinalis (rosemary) and Thymus vulgaris (thyme). Contact Dermatitis 2007;56(1):49-50.
  10. Jukic, M., Politeo, O., Maksimovic, M., Milos, M., and Milos, M. In vitro acetylcholinesterase inhibitory properties of thymol, carvacrol and their derivatives thymoquinone and thymohydroquinone. Phytother.Res 2007;21(3):259-261.
  11. Marzian, O. [Treatment of acute bronchitis in children and adolescents. Non-interventional postmarketing surveillance study confirms the benefit and safety of a syrup made of extracts from thyme and ivy leaves]. MMW.Fortschr.Med 6-28-2007;149(27-28 Suppl
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  14. Smeenk, G., Kerckhoffs, H. P., and Schreurs, P. H. Contact allergy to a reaction product in Hirudoid cream: an example of compound allergy. Br.J Dermatol. 1987;116(2):223-231.
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  18. Erol S, Aydin B, Dilli D, Okumus N, Zenciroglu A, Gündüz M. An interesting newborn case of fructose 1-6 diphosphatase deficiency triggered after thyme juice ingestion. Clin Lab. 2014;60(1):151-3. PubMed

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Eucalyptus 23 references
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Sundew 1 reference
  1. Sundew — MedlinePlus / U.S. National Library of Medicine Source

See these in context on the Sundew monograph →

Propolis 21 references
  1. Hay KD, Greig DE. Propolis allergy: a cause of oral mucositis with ulceration. Oral Surg Oral Med Oral Pathol 1990;70:584-6. PubMed
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  5. Hsu, C. Y., Chiang, W. C., Weng, T. I., Chen, W. J., and Yuan, A. Laryngeal edema and anaphalactic shock after topical propolis use for acute pharyngitis. Am J Emerg.Med 2004;22(5):432-433. PubMed
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  12. Lamoureux A, Meharon M, Durand AL, Darrigade AS, Doutre MS, Milpied B. A first case of erythema multiforme-like contact dermatitis caused by propolis. Contact Dermatitis. 2017;77(4):263-264. PubMed
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See these in context on the Propolis monograph →

Marshmallow 5 references
  1. Monographs on the medicinal uses of plant drugs. Exeter, UK: European Scientific Co-op Phytother, 1997.
  2. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
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  5. Hage-Sleiman R, Mroueh M, Daher CF. Pharmacological evaluation of aqueous extract of Althaea officinalis flower grown in Lebanon. Pharm Biol 2011;49(3):327-33.

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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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