Major interaction on record — check this product against your medications before combining. Check your meds →
Dietary supplement

Seasonal Defense Ingredients & Drug Interactions

by Nature's Sunshine

Capsule Category: Botanical
Most serious interaction: Major
The interaction bottom line Most serious interaction: Major

Seasonal Defense is a dietary supplement by Nature's Sunshine with 5 active ingredients. Its ingredients are commonly taken for fatigue and low energy, physical and athletic performance, stress resistance (adaptogen).Based on those ingredients, 1,458 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Eleuthero, Bitter Orange Fruit, Andrographis paniculata whole plant extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Seasonal Defense by Nature's Sunshine

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

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 0 of its 5 active ingredients.
  • “Proprietary Blend” is a proprietary blend — the label gives one combined amount (470 mg) without saying how much of each component you get.

Seasonal Defense contains five active ingredients: eleuthero, oregano, andrographis paniculata (whole plant extract), thyme, and bitter orange fruit, all delivered in capsule form. Eleuthero is included as an adaptogenic herb traditionally used to support energy and resilience.

Oregano, andrographis, and thyme are antimicrobial and antioxidant herbs often chosen for seasonal wellness support. Bitter orange fruit is added for its stimulant properties.

The product also contains inactive ingredients (magnesium stearate, silicon dioxide, gelatin, and water) as binders and capsule material.

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: immune system support during seasonal changes.
  • We looked for evidence on: Common cold, Influenza, Cough, Acute bronchitis, Bronchitis, Laryngitis — and 4 related terms.
  • The closest evidence on file: Oregano is rated "Insufficient Reliable Evidence To Rate" for Bronchitis (Natural Medicines).
  • Also on file: Oregano is rated "Insufficient Reliable Evidence To Rate" for Cough.
  • Also on file: Thyme is rated "Insufficient Reliable Evidence To Rate" for Bronchitis, Common cold, Cough, Laryngitis.

The evidence for Seasonal Defense's ingredients is mixed and often limited. Eleuthero is rated possibly effective for genital herpes, but evidence for its use in other conditions—chronic fatigue, bipolar disorder, osteoporosis, and familial Mediterranean fever—is insufficient.

Andrographis shows possibly effective evidence for ulcerative colitis, tonsillopharyngitis (throat inflammation), and osteoarthritis, but not for familial Mediterranean fever. Oregano, thyme, and bitter orange lack sufficient evidence in our data to support claims for acne, bronchitis, asthma, headache, upper respiratory infection, aging skin, alopecia, common cold, hay fever, sexual dysfunction, anxiety, or athletic performance.

If a particular condition is your reason for considering this product, check those ingredient ratings against your goal.

The evidence, ingredient by ingredient Eleuthero Oregano Andrographis Thyme Bitter Orange

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

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

Why this rating?
  • We hold adverse-effect (side-effect) data for 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Eleuthero is generally well tolerated for short-term use, though evidence on long-term safety is limited; it's best avoided during pregnancy and breastfeeding. Oregano is safe in food amounts but less studied in concentrated supplements; supplement amounts should be avoided during pregnancy, and breastfeeding safety isn't established.

Andrographis is generally well tolerated short-term but should be avoided during pregnancy due to theoretical reproductive concerns and during breastfeeding due to insufficient safety data. Thyme is likely safe in food and medicinal amounts during pregnancy and breastfeeding but concentrated essential oil should be avoided.

Bitter orange should not be used in supplement amounts during pregnancy or breastfeeding due to stimulant effects and lack of safety data. Common side effects across these ingredients include gastrointestinal upset, headache, nausea, and dizziness.

Eleuthero may cause nervousness, anxiety, or irritability, especially at higher doses. Oregano and andrographis can rarely cause severe allergic reactions, including anaphylaxis.

Bitter orange carries cardiovascular risks (high blood pressure, rapid heartbeat) particularly when combined with caffeine or other stimulants, and in rare cases has been linked to heart attack, stroke, and abnormal heart rhythms.

Side effects, ingredient by ingredient Eleuthero Oregano Andrographis Thyme Bitter Orange

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?
  • 5 of the 5 matched ingredients can interact with medications — Oregano, Thyme, Andrographis, Bitter Orange, Eleuthero.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications.
  • For scale: 1,459 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking Seasonal Defense, double-check the following medication types with your doctor or pharmacist, starting with the most serious: monoamine oxidase inhibitors (MAOIs) for depression, and midazolam or other sedatives. Also clear it with your doctor if you take blood thinners (anticoagulants) or antiplatelet drugs, any heart or blood-pressure medications (especially QT-prolonging drugs), antidiabetes drugs, immunosuppressants, stimulants, caffeine supplements, dextromethorphan (cough suppressant), heartbeat regulators like digoxin, estrogen therapy, anticholinergic or cholinergic drugs, pain relievers (etoricoxib or celecoxib), or any drug metabolized by the liver (CYP1A2, CYP2C9, CYP2D6, or CYP3A4 substrates).

No interactions are documented for the proprietary blend itself, but we hold no separate safety data for it.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with no established evidence rating for its marketed use. Major medication interactions have been identified, and safety information is well characterized.

Seasonal Defense may appeal to people seeking herbal support for seasonal wellness, though evidence for most of its uses is limited or insufficient. Because this product interacts with a large number of medications—including blood thinners, heart drugs, diabetes medications, and antidepressants—you'll want to check every prescription, over-the-counter drug, and other supplement you take against our search tool before starting.

Pregnant and breastfeeding individuals should avoid this product. Discuss it with your own doctor or pharmacist to confirm it's appropriate for your health situation and medications.

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

Assessment coverage: 5 of 5 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Oct 1, 2012.

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

At a glance

General information

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

Brand Nature's Sunshine
Net contents 90 Capsule(s)
Market status On market
Date entered into DSLD Oct 1, 2012
DSLD ID 13735
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegetarian, Adult (18 - 50 Years), Kosher, Dairy Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Seasonal Defense by Nature's Sunshine, 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:
1 Capsule(s)
IngredientAmount% DV
Proprietary Blend470 mg--
Eleuthero0 NP--
Oregano0 NP--
Andrographis paniculata whole plant extract0 NP--
Thyme0 NP--
Bitter Orange Fruit0 NP--

Other ingredients: Magnesium Stearate, Silicon Dioxide, Gelatin, Water

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

Other Information: GUARANTEED PURE Immune System Support -Helps the Body Maintain Optimal Health During Seasonal Health Changes -Andrographis Specifically Helps Boost the Immune System, Minimizing the Duration of Seasonal Health Changes -This Unique Formulation Helps Support Mucous Membranes*

This is a unique combination of herbal ingredients that help the body maintain optimal health during seasonal changes. Andrographis paniculata is an immune and respiratory-supporting agent backed with scientific documentation that helps minimize the length and severity of seasonal health changes.*

Product of U.S.A.

Nature's Sunshine uses natural source materials in its products that are subject to color variation.

Seasonal Defense (90 caps)

Seals/Symbols

Ko

Nature's Sunshine QUALITY, SERVICE INTEGRITY(R)

FDA Disclaimer Statement

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Precautions

This bottle was sealed for your protection. Do not use if inner seal is missing or damaged.

Warning: NOTICE: Pregnant or lactating women should consult their health-care provider prior to taking this supplement.

FDA Statement of Identity

Description: Herbal Combination Supplement-480 mg each

Suggested/Recommended/Usage/Directions

Recommended Usage: Take one capsule with a meal three times daily.

Brand IP Statement(s)

Nature's Sunshine(R) United States

See for yourself

Seasonal Defense by Nature's Sunshine label

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

What’s inside

The Ingredients in Seasonal Defense by Nature's Sunshine

These are the 5 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule 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.

Proprietary Blend

470 mg per serving

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

Interaction report

Seasonal Defense by Nature's Sunshine Drug Interactions

Want to check YOUR meds against Seasonal Defense?

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

Go to the checker
1,458Drugs
10 Major 1,407 Moderate 41 Minor

Ingredients driving the most interactions

Eleuthero 1,140
Thyme 379
Oregano 208

Each ingredient & the kinds of drugs it affects

For each ingredient in Seasonal Defense 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.

Eleuthero10 drug types · 1,140 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, eleuthero may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
In vitro and animal research shows that a constituent of eleuthero, dihydroxybenzoic acid, appears to inhibit platelet aggregation. Concomitant use with anticoagulant or antiplatelet drugs might increase the risk of bleeding. This effect has not been reported in humans.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, eleuthero might have additive effects when used with antidiabetes drugs.
Animal research suggests that certain constituents of eleuthero have hypoglycemic activity in both healthy and diabetic animals. A small study in adults with type 2 diabetes also shows that taking eleuthero for 3 months can lower blood glucose levels. However, one very small study in healthy individuals shows that taking powdered eleuthero 3 grams, 40 minutes prior to a 75-gram oral glucose tolerance test, significantly increases postprandial blood glucose levels when compared with placebo. These contradictory findings might be due to patient-specific variability and variability in active ingredient ratios.

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

Theoretically, eleuthero might increase levels of drugs metabolized by CYP1A2.
In vitro and animal research suggest that standardized extracts of eleuthero inhibit CYP1A2. This effect has not been reported in humans.

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

Theoretically, eleuthero might increase levels of drugs metabolized by CYP2C9.
In vitro and animal research suggest that standardized extracts of eleuthero might inhibit CYP2C9. This effect has not been reported in humans.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Eleuthero might increase serum digoxin levels and increase the risk of side effects.
In one case report, a 74-year-old male who was stabilized on digoxin presented with an elevated serum digoxin level after starting an eleuthero supplement, without symptoms of toxicity. After stopping the supplement, serum digoxin levels returned to normal. It is not clear whether this was due to a pharmacokinetic interaction or to interference with the digoxin assay. Although the product was found to be free of digoxin and digitoxin, it was not tested for other contaminants.

Likelihood Unlikely Evidence D
Immunosuppressants

Theoretically, eleuthero might interfere with immunosuppressive drugs because of its immunostimulant activity.
Animal and in vitro research shows that eleuthero extracts have immunomodulatory effects, including increasing cellular and humoral activity.

Likelihood Possible Evidence D
P-Glycoprotein Substrates

Theoretically, eleuthero might increase levels of P-glycoprotein substrates.
In vitro research suggests that eleuthero can inhibit the multi-drug transporter protein, P-glycoprotein. However, it is too soon to tell if this is clinically important. This interaction has not been reported in humans.

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

Theoretically, eleuthero might increase levels of drugs metabolized by CYP2D6.
In vitro and animal research suggest that standardized extracts of eleuthero might inhibit CYP2D6. However, research in healthy human volunteers has found that taking eleuthero 485 mg twice daily for 14 days does not inhibit CYP2D6 drug metabolism.

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

Theoretically, eleuthero might increase levels of drugs metabolized by CYP3A4.
In vitro and animal research suggest that standardized extracts of eleuthero might inhibit CYP3A4. However, research in healthy human volunteers has found that taking eleuthero 485 mg twice daily for 14 days does not inhibit CYP3A4 drug metabolism.

Likelihood Unlikely Evidence B
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Theoretically, eleuthero might decrease levels of drugs metabolized by OATP.
In vitro research suggests that eleuthero inhibits OATP2B1, which might reduce the bioavailability of oral drugs that are substrates of OATP2B1. Due to the weak inhibitory effect identified in this study, this interaction is not likely to be clinically significant.

Likelihood Possible Evidence D

Bitter Orange Fruit13 drug types · 957 drugs

Midazolam (Versed)

Bitter orange might increase blood levels of midazolam.
One small clinical study shows that bitter orange juice can increase midazolam levels, likely through inhibition of cytochrome P450 3A4 (CYP3A4). Theoretically, bitter orange might increase the risk of midazolam-related adverse effects.

Likelihood Probable Evidence B
Monoamine Oxidase Inhibitors (Maois)

Theoretically, taking MAOIs with synephrine-containing bitter orange preparations might increase the hypertensive effects of synephrine, potentially leading to hypertensive crisis.
Bitter orange contains tyramine, octopamine, and synephrine, which are MAO substrates.

Likelihood Probable Evidence D
Antidiabetes Drugs

Theoretically, bitter orange might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Some clinical research shows that drinking a tea containing bitter orange and Indian snakeroot reduces fasting and postprandial glucose levels in patients with type 2 diabetes who are using antidiabetes drugs. However, it is unclear if these effects are due to bitter orange, Indian snakeroot, or the combination. An animal study also shows that p-synephrine in combination with gliclazide , a sulfonylurea, causes an additional 20% to 44% decrease in glucose levels when compared with gliclazide alone.

Likelihood Possible Evidence B
Caffeine

Bitter orange might increase blood pressure and heart rate when taken with caffeine.
Small clinical studies show that taking bitter orange in combination with caffeine can increase blood pressure and heart rate in otherwise healthy normotensive adults. Theoretically, this might increase the risk of serious cardiovascular adverse effects.

Likelihood Possible Evidence B
Colchicine

Bitter orange might affect colchicine levels.
Colchicine is a substrate of P-glycoprotein and cytochrome P450 3A4 (CYP3A4). Bitter orange has been reported to inhibit CYP3A4 and increase levels of CYP3A4 substrates. However, one small clinical study in healthy adults shows that drinking bitter orange juice 240 mL twice daily for 4 days and taking a single dose of colchicine 0.6 mg on the 4th day decreases colchicine peak serum levels by 24%, time to peak serum level by 1 hour, and overall exposure to colchicine by 20%. The clinical significance of this finding is unclear.

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

Bitter orange might increase levels of drugs metabolized by CYP3A4.
Small clinical studies suggest that single or multiple doses of freshly squeezed bitter orange juice 200-240 mL can inhibit CYP3A4 metabolism of drugs, causing increased drug levels and potentially increasing the risk of adverse effects. However, the extent of the effect of bitter orange on CYP3A4-mediated drug interactions is unknown. Some evidence suggests that bitter orange selectively inhibits intestinal CYP3A4, but not hepatic CYP3A4. Its effect on P-glycoprotein, which strongly overlaps with CYP3A4 interactions, is unclear. One small clinical study shows that drinking 8 ounces of freshly squeezed bitter orange juice has no effect on cyclosporine, which seems to be more dependent on hepatic CYP3A4 and P-glycoprotein than intestinal CYP3A4.

Likelihood Possible Evidence B
Dextromethorphan (Robitussin Dm, Others)

Bitter orange might increase blood levels of dextromethorphan.
One small clinical study shows that bitter orange juice increases dextromethorphan levels, likely through cytochrome P450 3A4 (CYP3A4) inhibition. Theoretically, bitter orange might increase the risk for dextromethorphan-related adverse effects.

Likelihood Possible Evidence B
Felodipine (Plendil)

Bitter orange might increase blood levels of felodipine.
One small clinical study shows that bitter orange juice increases felodipine levels, likely through cytochrome P450 3A4 (CYP3A4) inhibition. Theoretically, bitter orange might increase the risk for felodipine-related adverse effects.

Likelihood Probable Evidence B
Indinavir (Crixivan)

Bitter orange might increase blood levels of indinavir.
One small clinical study shows that bitter orange juice slightly increases indinavir levels, but this effect is likely to be clinically insignificant. Bitter orange selectively inhibits intestinal cytochrome P450 3A4 (CYP3A4); however, the metabolism of indinavir seems to be more dependent on hepatic CYP3A4. The effect of bitter orange on other protease inhibitors has not been studied.

Likelihood Possible Evidence B
Qt Interval-Prolonging Drugs

Theoretically, bitter orange might have an additive effect when combined with drugs that prolong the QT interval, potentially increasing the risk of ventricular arrhythmias.
One case report suggests that taking bitter orange in combination with other stimulants such as caffeine might prolong the QT interval in some patients.

Likelihood Possible Evidence D
Sildenafil (Viagra)

Bitter orange juice might increase blood levels of sildenafil.
A small clinical study in healthy adult males shows that drinking freshly squeezed bitter orange juice 250 mL daily for 3 days and taking a single dose of sildenafil 50 mg on the 3rd day increases the peak plasma concentration of sildenafil by 18% and the overall exposure to sildenafil by 44%. Theoretically, this may be due to inhibition of cytochrome P450 3A4 by bitter orange.

Likelihood Probable Evidence B
Stimulant Drugs

Theoretically, bitter orange might increase the risk of hypertension and adverse cardiovascular effects when taken with stimulant drugs.
Bitter orange appears to have stimulant effects.

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

Theoretically, bitter orange might increase levels of drug metabolized by CYP2D6.
In vitro research shows that octopamine, a constituent of bitter orange, weakly inhibits CYP2D6 enzymes. This effect has not been reported in humans.

Likelihood Possible Evidence D

Andrographis paniculata whole plant extract6 drug types · 413 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, andrographis might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Animal and laboratory studies suggest that andrographis has antiplatelet effects.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, andrographis might increase the risk of hypotension when used with antihypertensive drugs.
Animal research suggests that andrographis has hypotensive effects.

Likelihood Possible Evidence D
Immunosuppressants

Theoretically, andrographis might interfere with the effects of immunosuppressive drugs.
Laboratory research suggests that andrographolide has immunostimulant activity.

Likelihood Possible Evidence D
Celecoxib (Celebrex)

Theoretically, andrographis extract might increase the maximum concentration and time to peak concentration of celecoxib. The clinical significance of these changes is unclear.
Animal research suggests that andrographis extract taken orally increases the maximum concentration and time to peak concentration of celecoxib but does not appear to impact the area under the curve.

Likelihood Possible Evidence D
Etoricoxib (Arcoxia)

Theoretically, andrographis might decrease the absorption of etoricoxib, although the clinical significance is unclear.
Animal research shows that andrographis extract, or the constituent andrographolide, taken orally with etoricoxib decreases the bioavailability of etoricoxib. However, this reduced bioavailability is not correlated with a reduction in the anti-inflammatory effects of etoricoxib in arthritic mice models. The clinical significance of this interaction is unclear.

Likelihood Possible Evidence D
Glipizide (Glucotrol)

Theoretically, andrographis extract might increase the maximum concentration and area under the curve of glipizide; however, opposite effects are seen with the constituent, andrographolide. The clinical significance of this interaction is unclear.
Animal research suggests that andrographis extract taken orally with glipizide in diabetes-induced rats increases the maximum concentration and area under the curve of glipizide. However, the opposite effect is seen with the constituent, andrographolide, in which the maximum concentration and area under the curve are decreased when taken with glipizide.

Likelihood Possible Evidence D

Thyme4 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

Oregano2 drug types · 208 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, oregano might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
In vitro research shows that aristolochic acid isolated from oregano leaves has antithrombin activity. It has also been reported that oregano oil inhibits arachidonic acid-induced, and ADP-induced, platelet aggregation.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, oregano might increase the risk for hypoglycemia when taken with antidiabetes drugs.
In vitro and animal research shows that oregano extracts might lower blood glucose levels.

Likelihood Possible Evidence D
The maker

Brand information

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

Nature's Sunshine

See all Nature's Sunshine products
Name
Nature's Sunshine Products, Inc.
Pharmacist Counseling Corner

Seasonal Defense by Nature's Sunshine: Common Questions

Does Seasonal Defense by Nature's Sunshine interact with any medications?
Yes. Based on its ingredients, Seasonal Defense has a known interaction with 1,458 medications, including 10 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Seasonal Defense contains 5 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take Seasonal Defense if I'm pregnant or breastfeeding?
No. Eleuthero, andrographis, and bitter orange should all be avoided during pregnancy due to insufficient safety data or theoretical reproductive concerns. Oregano in medicinal amounts and bitter orange in supplement amounts should also be avoided during pregnancy. For breastfeeding, eleuthero, andrographis, and bitter orange are not recommended due to lack of safety information, and oregano supplement safety isn't established. Talk with your doctor or pharmacist about safer options.
Does this product really help with colds and seasonal illness?
The evidence in our data is insufficient for most of the conditions these herbs are traditionally used for—including upper respiratory infection, bronchitis, common cold, and hay fever. Andrographis does show possibly effective evidence for tonsillopharyngitis (sore throat), but the other ingredients lack established proof of benefit for cold-season wellness.
What are the most common side effects?
The most common side effects are gastrointestinal upset, headache, nausea, and dizziness. Eleuthero may also cause nervousness or anxiety, especially at higher doses. Oregano and andrographis can cause rash or allergic reactions in some people. Bitter orange, particularly if combined with caffeine, can raise blood pressure and heart rate.
Is Seasonal Defense safe to use long-term?
Long-term safety is not well established. Eleuthero and andrographis are generally well tolerated short-term, but evidence for prolonged use is limited. Concentrated oregano oil is less studied than food amounts. If you're considering taking this for several months, check with your doctor or pharmacist first.
Why does this product have so many medication interactions?
Bitter orange is the main driver—it contains stimulant compounds that inhibit liver enzymes and interact with many medications, including MAOIs and sedatives. Eleuthero and andrographis also affect how your liver processes certain drugs. Even though most of these interactions are theoretical (shown in lab studies but not yet reported in people), they matter if you take any of the affected medications.
Can I take this with caffeine or energy drinks?
No. Bitter orange combined with caffeine can significantly raise blood pressure and heart rate and theoretically increase the risk of serious heart problems. If you consume caffeine regularly, avoid this product.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Seasonal Defense label
Go deeper

The Full Monographs Behind Seasonal Defense’s Ingredients

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

Sources

Sources & How We Checked

Seasonal Defense'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 127 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.

Eleuthero 24 references
  1. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  2. McRae S. Elevated serum digoxin levels in a patient taking digoxin and Siberian ginseng. CMAJ 1996;155:293-5.
  3. Awang DVC. Siberian ginseng toxicity may be case of mistaken identity (letter). CMAJ 1996;155:1237.
  4. Mills S, Bone K. Principles and Practice of Phytotherapy. London: Churchill Livingstone, 2000.
  5. Harkey MR, Henderson GL, Zhou L, et al. Effects of Siberian ginseng (Eleutherococcus senticosus) on c-DNA-expressed P450 drug metabolizing enzymes. Alt Ther 2001;7:S14.
  6. Hikino H, Takahashi M, Otake K, Konno C. Isolation and hypoglycemic activity of eleutherans A, B, C, D, E, F, and G: glycans of Eleutherococcus senticosus roots. J Nat Prod 1986;49:293-7. PubMed
  7. Yun-Choi HS, Kim JH, Lee JR. Potential inhibitors of platelet aggregation from plant sources, III. J Nat Prod 1987;50:1059-64. PubMed
  8. Donovan JL, DeVane CL, Chavin KD, et al. Siberian Ginseng (Eleutheroccus senticosus) Effects on CYP2D6 and CYP3A4 Activity in Normal Volunteers. Drug Metab Dispos 2003;31:519-22.. PubMed
  9. Hartz AJ, Bentler S, Noyes R et al. Randomized controlled trial of Siberian ginseng for chronic fatigue. Psychol Med 2004;34:51-61. PubMed
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Oregano 12 references
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Andrographis 26 references
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