Major interaction on record — check this product against your medications before combining. Based on 6 of 11 ingredients. Check your meds →
Dietary supplement

S2 To S4 Para Ingredients & Drug Interactions

by Chiro-Zyme

S2 To S4 Para label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking S2 To S4 Para against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Major

S2 To S4 Para is a dietary supplement by Chiro-Zyme with 11 active ingredients. Its ingredients are commonly taken for digestion and bloating, muscle soreness and exercise recovery, inflammation and swelling.Based on those ingredients, 774 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Fenugreek, Shiitake, Horsetail. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against S2 To S4 Para by Chiro-Zyme

Ask about any prescription or over-the-counter medication and we check it for interactions with S2 To S4 Para by Chiro-Zyme — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of S2 To S4 Para by Chiro-Zyme

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

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Sep 10, 2026

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 4 of its 11 active ingredients.
  • “Proprietary Plant Enzyme Blend” is a proprietary blend — the label gives one combined amount (60 mg) without saying how much of each component you get.

Chiro-Zyme S2 To S4 Para is a digestive enzyme blend with 11 ingredients. The active components are proteases, lipase, and several other carbohydrate-digesting enzymes designed to support food breakdown, plus fenugreek seed, shiitake mushroom, calcium, and horsetail — traditional plant and mineral additions.

We hold no data on amylase, cellulase, glucoamylase, alpha-galactosidase, hemicellulase, or the proprietary plant enzyme blend's specific contents. The capsules also contain phytase and the capsule material itself as inactive ingredients.

Does it work?

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

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

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Hypocalcemia — rated "Effective" (Calcium) (Natural Medicines).
  • On file: Hyperkalemia — rated "Effective" (Calcium) (Natural Medicines).
  • On file: Dyspepsia — rated "Effective" (Calcium) (Natural Medicines).
  • On file: Kidney failure — rated "Effective" (Calcium) (Natural Medicines).
  • On file: Corticosteroid-induced osteoporosis — rated "Likely Effective" (Calcium) (Natural Medicines).

The evidence for this product's digestive enzyme ingredients is limited. Lipase and protease have no established effectiveness ratings in our data for any condition.

Fenugreek shows possibly effective evidence for sexual dysfunction and dysmenorrhea (period pain), and possibly effective for diabetes. Shiitake is rated possibly ineffective for dental plaque, with insufficient evidence for cancer-related conditions and atherosclerosis.

Horsetail has insufficient evidence for urinary incontinence, obesity, and hair loss. Overall, the main digestive enzyme components lack established efficacy data in our records.

The evidence, ingredient by ingredient Proteolytic Enzymes (proteases) Lipase Fenugreek Shiitake Mushroom Calcium Horsetail

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 6 of the 6 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 6 of 6.
  • General safety write-ups exist for 6 of 6.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Protease is generally well tolerated in adults but may cause digestive upset or allergic reactions; it's best avoided in pregnancy and use isn't recommended while breastfeeding without medical advice. Lipase is generally well tolerated in supplement form; there's limited safety data in pregnancy and breastfeeding, so check with your healthcare provider first.

Fenugreek is generally well tolerated in food amounts but supplement doses carry risk — it's likely unsafe in pregnancy due to possible uterine effects but possibly safe for breastfeeding to boost milk supply (with provider discussion). Shiitake is generally well tolerated as cooked food but concentrated supplements lack safety data; food amounts are likely fine in pregnancy and breastfeeding, but supplement doses need caution.

Calcium is generally safe at recommended amounts and safe in pregnancy and breastfeeding, though high doses raise theoretical concerns. Horsetail should be used short-term only by healthy adults — it's not recommended in pregnancy or breastfeeding due to insufficient safety data and historical concerns about thiamine deficiency with prolonged use.

Common side effects across these ingredients include digestive upset (bloating, gas, diarrhea, nausea), and rare but serious allergic reactions have been reported, especially with fenugreek and shiitake.

Side effects, ingredient by ingredient Proteolytic Enzymes (proteases) Lipase Fenugreek Shiitake Mushroom Calcium Horsetail

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?
  • 4 of the 6 matched ingredients can interact with medications — Shiitake Mushroom, Fenugreek, Calcium, Horsetail.
  • 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; lithium.
  • For scale: 774 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 Chiro-Zyme, double-check with your doctor or pharmacist if you take any of these: HIV medications called integrase inhibitors (especially dolutegravir or elvitegravir) or reverse transcriptase inhibitors — calcium and horsetail can interfere with them. Blood thinners like warfarin or antiplatelet drugs like clopidogrel — fenugreek may add to their effects.

Diabetes medications — both fenugreek and horsetail could lower blood sugar further. Heart and blood pressure drugs (metoprolol, sotalol, diltiazem) or thyroid hormone (levothyroxine) — calcium or fenugreek may reduce their effectiveness.

Diuretics, lithium, seizure medications (phenytoin), or theophylline — these all have documented interactions with ingredients in this blend. No interactions are documented for the ingredients we could not check (amylase, cellulase, glucoamylase, alpha-galactosidase, hemicellulase, and the proprietary plant enzyme blend).

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with strong clinical evidence behind its ingredients' uses. Major medication interactions have been identified, and safety information is well characterized.

This product may appeal to those looking for digestive enzyme support, though evidence for most of its active ingredients is limited. If you take HIV medications, thyroid hormone, blood thinners, diabetes drugs, heart medications, diuretics, or lithium, talk with your doctor or pharmacist before starting — several ingredients pose documented interactions that could affect how your drugs work.

The same goes for anyone on immunosuppressants or anti-seizure medications. Pregnant or breastfeeding women should check with their provider first, particularly around fenugreek and horsetail.

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

Assessment coverage: 6 of 11 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Apr 25, 2018.

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 S2 To S4 Para, straight from the product label.

Brand Chiro-Zyme
Barcode (UPC) 697706004618
Net contents 180 Capsule(s)
Market status On market
Date entered into DSLD Apr 25, 2018
DSLD ID 176513
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for S2 To S4 Para by Chiro-Zyme, 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 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
90
UPC/BARCODE
697706004618
IngredientAmount% DV
Amylase0 NP--
Protease0 NP--
Lipase0 NP--
Cellulase0 NP--
Glucoamylase0 NP--
Alpha-Galactosidase0 NP--
Hemicellulase0 NP--
Proprietary Plant Enzyme Blend60 mg--
Fenugreek200 mg--
Shiitake70 mg--
Calcium52 mg5%
Horsetail140 mg--

Other ingredients: Capsule, Phytase

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.
Brand IP Statement(s)

pHBS pH balancing system

EFI Enzyme Formulations, Inc.

FDA Disclaimer Statement

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

Precautions

Keep out of reach of children

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

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

Storage

To ensure freshness and potency, keep bottle tightly closed and store in a cool, dry place.

General

I-64188-3

FDA Statement of Identity

A Dietary Supplement

Suggested/Recommended/Usage/Directions

Directions for use: Take 2 capsules, 3 times daily after meals or as directed.

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

See for yourself

S2 To S4 Para by Chiro-Zyme label

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

S2 To S4 Para 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 S2 To S4 Para by Chiro-Zyme

These are the 11 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container90 Amounts shown are per serving.

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

Proprietary Plant Enzyme Blend

60 mg per serving
  • › Amylase
  • › Protease
  • › Lipase
  • › Cellulase
  • › Glucoamylase
  • › Alpha-Galactosidase
  • › Hemicellulase

Fenugreek

Interacts with
389 drugs
200 mg per serving

Fenugreek is a common kitchen spice that is also taken as a supplement, mainly for blood sugar, cholesterol, and to support breast milk production. So...

Fenugreek monograph & interactions

Shiitake

Interacts with
312 drugs
70 mg per serving

Shiitake is a popular edible mushroom that is nutritious and safe to eat as food for most people. Some of its extracts (like lentinan and AHCC) have b...

Shiitake monograph & interactions

Calcium

Interacts with
168 drugs
52 mg per serving Form: Calcium Lactate, Tricalcium Phosphate

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet f...

Calcium monograph & interactions

Horsetail

Interacts with
188 drugs
140 mg per serving

Horsetail is a traditional herb most often used as a mild diuretic and for hair, nail, and bone support, but high-quality human evidence is limited. I...

Horsetail monograph & interactions

Other (inactive) ingredients: Capsule, Phytase. These complete the product’s ingredient list but are not active constituents.

Interaction report

S2 To S4 Para by Chiro-Zyme Drug Interactions

Want to check YOUR meds against S2 To S4 Para?

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
774Drugs
7 Major 679 Moderate 88 Minor

Ingredients driving the most interactions

Fenugreek 389
Shiitake 312
Horsetail 188
Calcium 168

Individual Drug Interactions

The ingredients in S2 To S4 Para interact with 774 drugs. Click any drug to see the details.

4 of the 11 ingredients in S2 To S4 Para interact with drugs. Each result below shows which ingredient is responsible. Fenugreek Shiitake Horsetail Calcium

Each ingredient & the kinds of drugs it affects

For each ingredient in S2 To S4 Para 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.

Fenugreek9 drug types · 389 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, fenugreek might have additive effects when used with anticoagulant or antiplatelet drugs.
Some of the constituents in fenugreek have antiplatelet effects in animal and in vitro research. However, common fenugreek products might not contain sufficient concentrations of these constituents for clinical effects. A clinical study in patients with coronary artery disease or diabetes shows that taking fenugreek seed powder 2.5 grams twice daily for 3 months does not affect platelet aggregation, fibrinolytic activity, or fibrinogen levels .

Likelihood Unlikely Evidence B
Antidiabetes Drugs

Theoretically, fenugreek seed might have additive hypoglycemic effects when used with antidiabetes drugs.
Clinical research shows that fenugreek seed can reduce fasting blood glucose and 2-hour postprandial glucose levels in adults with type 2 diabetes.

Likelihood Probable Evidence B
Clopidogrel (Plavix)

Theoretically, fenugreek seed might alter the clinical effects of clopidogrel by inhibiting its conversion to the active form.
Animal research shows that fenugreek seed 200 mg/kg daily for 14 days increases the maximum serum concentration of clopidogrel by 21%. It is unclear how this affects the pharmacokinetics of the active metabolite of clopidogrel; however, this study found that concomitant use of fenugreek seed and clopidogrel prolonged bleeding time by an additional 11%.

Likelihood Possible Evidence D
Metoprolol (Toprol)

Theoretically, fenugreek seed might have additive hypotensive effects when used with metoprolol.
Animal research shows that fenugreek seed 300 mg/kg daily for 2 weeks decreases systolic and diastolic blood pressure by 9% and 11%, respectively, when administered alone, and by 15% and 22%, respectively, when given with metoprolol 10 mg/kg.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Theoretically, fenugreek might decrease plasma levels of phenytoin.
Animal research shows that taking fenugreek seeds for 1 week decreases maximum concentrations and the area under the curve of a single dose of phenytoin by 44% and 72%, respectively. This seems to be related to increased clearance. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Sildenafil (Viagra)

Theoretically, concurrent use of sildenafil and fenugreek might reduce levels and therapeutic effects of sildenafil.
Animal research shows that taking fenugreek seeds for 1 week reduces maximum concentrations and the area under the curve of a single dose of sildenafil by 27% and 48%, respectively. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Theophylline

Theoretically, fenugreek may reduce the levels and clinical effects of theophylline.
Animal research shows that fenugreek 50 grams daily for 7 days reduces the maximum serum concentration (Cmax) of theophylline by 28% and the area under the plasma drug concentration-time curve (AUC) by 22%.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, fenugreek might have additive effects with warfarin and increase the international normalized ratio (INR).
Some fenugreek constituents have antiplatelet effects, although these might not be present in concentrations that are clinically significant. In one case report, a patient taking warfarin experienced an increased INR when starting to take fenugreek in combination with boldo.

Likelihood Possible Evidence D
Antihypertensive Drugs

Fenugreek may also have an additive effect on blood pressure-lowering medications. Studies on animals have shown that fenugreek seed can decrease both systolic and diastolic blood pressure by up to 22% when combined with metoprolol. Therefore, it is essential to monitor your blood pressure regularly if you are taking fenugreek and metoprolol together or any other antihypertensive drugs.

Likelihood Possible Evidence C
Fenugreek full monograph & interactions

Shiitake2 drug types · 312 drugs

Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, shiitake mushroom might decrease levels of drugs metabolized by CYP2D6.
In vitro studies suggest that the shiitake mushroom extract AHCC might induce the CYP2D6 enzyme. This effect has not been reported in humans.

Likelihood Possible Evidence D
Immunosuppressants

Theoretically, taking shiitake mushroom might decrease the effects of immunosuppressive therapy.
In vitro evidence suggests that shiitake mushroom extracts stimulate immune function.

Likelihood Possible Evidence D
Shiitake full monograph & interactions

Horsetail5 drug types · 188 drugs

Antidiabetes Drugs

Theoretically, taking horsetail with antidiabetes drugs might increase the risk of hypoglycemia.
Equisetum myriochaetum has demonstrated hypoglycemic activity in clinical research. In an animal diabetic model, Equisetum giganteum had hypoglycemic effects. It is unclear whether other horsetail species have hypoglycemic effects.

Likelihood Possible Evidence D
Diuretic Drugs

Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Laboratory research shows that various species of horsetail have diuretic properties. Due to its diuretic effects, there has been concern that taking horsetail along with potassium-depleting diuretics might increase the risk for hypokalemia. However, pharmacokinetic research in humans shows that taking horsetail 900 mg daily for 4 days does not affect urinary excretion of electrolytes, including potassium and sodium, despite having a diuretic effect similar to taking hydrochlorothiazide 25 mg daily. It is unclear if taking horsetail for a longer duration would affect electrolyte levels. Until more is known, use with caution.

Likelihood Possible Evidence D
Efavirenz (Sustiva)

Theoretically, horsetail might decrease the levels and clinical effects of efavirenz.
In two case reports, patients were found to have detectable viral loads when taking horsetail-containing supplements along with an antiretroviral regimen that included efavirenz. In one case, the antiretroviral regimen included zidovudine, lamivudine, and efavirenz; in the other case, the regimen consisted of emtricitabine, tenofovir disoproxil fumarate, and efavirenz. One month after discontinuing horsetail, the viral loads became undetectable in both cases. The exact mechanism of this interaction is unknown. It is also unclear if this interaction is specific to efavirenz or if it is related to various components of antiretroviral therapy.

Likelihood Possible Evidence D
Lithium

Theoretically, horsetail might increase the levels and adverse effects of lithium.
Animal research suggests that horsetail has diuretic properties. Theoretically, due to these potential diuretic effects, horsetail might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Possible Evidence D
Nucleoside Reverse Transcriptase Inhibitors (Nrtis)

Theoretically, horsetail might decrease the levels and clinical effects of NRTIs.
In two case reports, patients were found to have detectable viral loads when taking horsetail-containing supplements along with an antiretroviral therapy. In one case, the antiretroviral regimen included zidovudine, lamivudine, and efavirenz; in the other case, the regimen consisted of emtricitabine, tenofovir disoproxil fumarate, and efavirenz. One month after discontinuing the supplement, the viral loads became undetectable in both cases. The exact mechanism of these interactions is unknown. It is also unclear if these interactions are specific to NRTIs or if they are related to various components of antiretroviral therapy.

Likelihood Possible Evidence D
Horsetail full monograph & interactions

Calcium18 drug types · 168 drugs

Ceftriaxone (Rocephin)

Co-administration of intravenous calcium and ceftriaxone can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys.
Avoid administering intravenous calcium in any form, such as parenteral nutrition or Lactated Ringers, within 48 hours of intravenous ceftriaxone. Case reports in neonates show that administering intravenous ceftriaxone and calcium can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys. In several cases, neonates have died as a result of this interaction. So far there are no reports in adults; however, there is still concern that this interaction might occur in adults.

Likelihood Probable Evidence D
Dolutegravir (Tivicay)

Calcium seems to reduce levels of dolutegravir.
Advise patients to take dolutegravir either 2 hours before or 6 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium carbonate 1200 mg concomitantly with dolutegravir 50 mg reduces plasma levels of dolutegravir by almost 40%. Calcium appears to decrease levels of dolutegravir through chelation.

Likelihood Probable Evidence B
Elvitegravir (Vitekta)

Calcium seems to reduce levels of elvitegravir.
Advise patients to take elvitegravir either 2 hours before or 2 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium along with elvitegravir can reduce blood levels of elvitegravir through chelation.

Likelihood Probable Evidence B
Aluminum

Calcium citrate might increase aluminum absorption and toxicity. Other types of calcium do not increase aluminum absorption.
Calcium citrate can increase the absorption of aluminum when taken with aluminum hydroxide. The increase in aluminum levels may become toxic, particularly in individuals with kidney disease. However, the effect of calcium citrate on aluminum absorption is due to the citrate anion rather than calcium cation. Calcium acetate does not appear to increase aluminum absorption.

Likelihood Possible Evidence B
Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Calcium might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide and calcium can be taken together if taken with food. However, if taken on an empty stomach, bictegravir/emtricitabine/tenofovir alafenamide should not be taken with, or 2 hours after, calcium containing products.

Likelihood Probable Evidence D
Bisphosphonates

Calcium reduces the absorption of bisphosphonates.
Advise patients to take bisphosphonates at least 30 minutes before calcium, but preferably at a different time of day. Calcium supplements decrease absorption of bisphosphonates.

Likelihood Probable Evidence C
Calcipotriene (Dovonex)

Taking calcipotriene with calcium might increase the risk for hypercalcemia.
Calcipotriene is a vitamin D analog used topically for psoriasis. It can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia. Theoretically, combining calcipotriene with calcium supplements might increase the risk of hypercalcemia.

Likelihood Possible Evidence B
Digoxin (Lanoxin)

Using intravenous calcium with digoxin might increase the risk of fatal cardiac arrhythmias.
Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. However, one retrospective analysis of clinical data suggests that intravenous calcium does not increase the risk of dysrhythmias or mortality in patients receiving digoxin.

Likelihood Possible Evidence B
Diltiazem (Cardizem, Others)

Theoretically, calcium may reduce the therapeutic effects of diltiazem.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, calcium might increase this risk of hypercalcemia and reduce the effectiveness of diltiazem.

Likelihood Probable Evidence D
Levothyroxine (Synthroid, Others)

Calcium seems to reduce the absorption and effectiveness of levothyroxine.
Advise patients to take levothyroxine and calcium supplements at least 4 hours apart. Calcium reduces levothyroxine absorption, probably by forming insoluble complexes. Calcium carbonate supplements reduce effectiveness of levothyroxine in patients with hypothyroidism.

Likelihood Probable Evidence B
Lithium

Theoretically, concomitant use of calcium and lithium may increase this risk of hypercalcemia.
Clinical research suggests that long-term use of lithium may cause hypercalcemia in 10% to 60% of patients. Theoretically, concomitant use of lithium and calcium supplements may further increase this risk.

Likelihood Possible Evidence B
Quinolone Antibiotics

Calcium seems to reduce the absorption of quinolone antibiotics.
Advise patients to take oral quinolones at least 2 hours before or 4-6 hours after calcium supplements or calcium-fortified foods. Taking calcium at the same time as oral quinolones can reduce quinolone absorption. Calcium binds to quinolones in the gut.

Likelihood Probable Evidence B
Raltegravir (Isentress)

Calcium may reduce levels of raltegravir.
Pharmacokinetic research shows that taking a single dose of calcium carbonate 3000 mg along with raltegravir 400 mg twice daily modestly decreases the mean area under the curve of raltegravir, but the decrease does not necessitate a dose adjustment of raltegravir. However, a case of elevated HIV-1 RNA levels and documented resistance to raltegravir has been reported for a patient taking calcium carbonate 1 gram three times daily plus vitamin D3 (cholecalciferol) 400 IU three times daily in combination with raltegravir 400 mg twice daily for 11 months. It is thought that calcium reduced raltegravir levels by chelation, leading to treatment failure.

Likelihood Possible Evidence B
Sotalol (Betapace)

Calcium seems to reduce the absorption of sotalol.
Advise patients to separate doses by at least 2 hours before or 4-6 hours after calcium. Calcium appears to reduce the absorption of sotalol, probably by forming insoluble complexes.

Likelihood Possible Evidence B
Tetracycline Antibiotics

Calcium seems to reduce the absorption of tetracycline antibiotics.
Advise patients to take oral tetracyclines at least 2 hours before, or 4-6 hours after calcium supplements. Taking calcium at the same time as oral tetracyclines can reduce tetracycline absorption. Calcium binds to tetracyclines in the gut.

Likelihood Probable Evidence C
Thiazide Diuretics

Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Thiazides reduce calcium excretion by the kidneys. Using thiazides along with moderately large amounts of calcium carbonate increases the risk of milk-alkali syndrome (hypercalcemia, metabolic alkalosis, renal failure). Patients may need to have their serum calcium levels and/or parathyroid function monitored regularly.

Likelihood Probable Evidence C
Verapamil (Calan, Others)

Theoretically, calcium may reduce the therapeutic effects of verapamil.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, use of calcium supplements may increase this risk of hypercalcemia and reduce the effectiveness of verapamil.

Likelihood Probable Evidence D
Calcium Channel Blockers

Intravenous calcium may decrease the effects of calcium channel blockers; oral calcium is unlikely to have this effect.
Intravenous calcium is used to decrease the effects of calcium channel blockers in the management of overdose. Intravenous calcium gluconate has been used before intravenous verapamil (Isoptin) to prevent or reduce the hypotensive effects without affecting the antiarrhythmic effects. But there is no evidence that dietary or supplemental calcium when taken orally interacts with calcium channel blockers.

Likelihood Unlikely Evidence D
Calcium full monograph & interactions
The maker

Brand information

Manufacturer and brand details for S2 To S4 Para, from the product label.

Chiro-Zyme

See all Chiro-Zyme products
Name
Enzyme Formulations, Inc.
City
Madison
State
Wisconsin
ZipCode
53719
Phone Number
1-800-614-4400
Web Address
www.enzymeformulations.com
Pharmacist Counseling Corner

S2 To S4 Para by Chiro-Zyme: Common Questions

Does S2 To S4 Para by Chiro-Zyme interact with any medications?
Yes. Based on its ingredients, S2 To S4 Para has a known interaction with 774 medications, including 7 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
S2 To S4 Para contains 11 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 it safe to take Chiro-Zyme while pregnant?
Not without talking to your doctor first. Fenugreek is likely unsafe in pregnancy, and horsetail and protease aren't recommended due to insufficient safety data. Lipase and calcium have limited pregnancy data as well. Check with your healthcare provider to see if this product is right for you during pregnancy.
Can I take Chiro-Zyme while breastfeeding?
There isn't enough safety data on most ingredients during breastfeeding. Fenugreek is possibly safe and sometimes used to boost milk supply, but that should be discussed with your provider. Protease, lipase, horsetail, and shiitake all lack sufficient breastfeeding data — talk with your healthcare provider first.
What side effects might I experience from this product?
The most common are digestive — bloating, gas, diarrhea, nausea, and stomach upset. Rare but serious allergic reactions including swelling, wheezing, and bronchospasm have been reported, especially with fenugreek and shiitake. Stop and seek immediate care if you experience signs of allergy.
Does this product actually help with digestion?
The evidence is limited. Protease and lipase don't have established effectiveness ratings in our data. Fenugreek, shiitake, and horsetail lack sufficient evidence for digestive support specifically. If you're considering this for a digestive condition, discuss it with your doctor or pharmacist first.
What is the proprietary plant enzyme blend in this product?
The ingredient list notes it's a proprietary blend, which means the exact contents and amounts aren't disclosed. We hold no separate interaction or safety data on what's inside it, so we can't check it for you independently. Ask the manufacturer for details if you need to know the specific enzymes included.

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

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Go deeper

The Full Monographs Behind S2 To S4 Para’s Ingredients

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

Herb & supplement monograph

Proteolytic Enzymes (proteases)

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

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

Lipase

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

Read the full Lipase monograph → Herb & supplement monograph

Fenugreek

Interacts with 389 drugs

Fenugreek is a common kitchen spice that is also taken as a supplement, mainly for blood sugar, cholesterol, and to support breast milk production. Some early research is encouraging for blo...

Read the full Fenugreek monograph → Herb & supplement monograph

Shiitake Mushroom

Interacts with 312 drugs

Shiitake is a popular edible mushroom that is nutritious and safe to eat as food for most people. Some of its extracts (like lentinan and AHCC) have been studied as immune support, mainly al...

Read the full Shiitake Mushroom monograph → Herb & supplement monograph

Calcium

Interacts with 168 drugs

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet falls short. Most people do best getting...

Read the full Calcium monograph → Herb & supplement monograph

Horsetail

Interacts with 188 drugs

Horsetail is a traditional herb most often used as a mild diuretic and for hair, nail, and bone support, but high-quality human evidence is limited. It can cause thiamine (vitamin B1) loss w...

Read the full Horsetail monograph →
Sources

Sources & How We Checked

S2 To S4 Para'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 177 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.

Proteolytic Enzymes (proteases) 3 references
  1. Weeks JA, Harper RA, Simon RA, Burdick JD. Assessment of sensitization risk of a laundry pre-spotter containing protease. Cutan Ocul Toxicol. 2011;30(4):272-9. PubMed
  2. Marquès LI, Lara S, Abós T, Bartolomé B. Occupational rhinitis due to pepsin. J Investig Allergol Clin Immunol. 2006;16(2):136-7. DOI
  3. Cartier A, Malo JL, Pineau L, Dolovich J. Occupational asthma due to pepsin. J Allergy Clin Immunol. 1984;73(5 Pt 1):574-7. PubMed

See these in context on the Proteolytic Enzymes (proteases) monograph →

Lipase 1 reference
  1. Casper C, Hascoet JM, Ertl T, et al. Recombinant bile salt-stimulated lipase in preterm infant feeding: A randomized phase 3 study. PLoS One. 2016;11(5):e0156071. PubMed

See these in context on the Lipase monograph →

Fenugreek 30 references
  1. Madar Z, Thorne R. Dietary fiber. Prog Food Nutr Sci 1987;11:153-74.
  2. Sharma RD, Raghuram TC, Rao NS. Effect of fenugreek seeds on blood glucose and serum lipids in type I diabetes. Eur J Clin Nutr 1990;44:301-6.
  3. Patil SP, Niphadkar PV, Bapat MM. Allergy to fenugreek (Trigonella foenum graecum). Ann Allergy Asthma Immunol 1997;78:297-300. PubMed
  4. Lambert J, Cormier J. Potential interaction between warfarin and boldo-fenugreek. Pharmacotherapy 2001;21:509-12. PubMed
  5. Bordia A, Verma SK, Srivastava KC. Effect of ginger (Zingiber officinale Rosc.) and fenugreek (Trigonella foenumgraecum L.) on blood lipids, blood sugar and platelet aggregation in patients with coronary artery disease. Prostaglandins Leukot Essent Fatty PubMed
  6. Yalcin SS, Tekinalp G, Ozalp I. Peculiar odor of traditional food and maple syrup urine disease. Pediatr Int 1999;41:108-9. PubMed
  7. Sewell AC, Mosandl A, Bohles H. False diagnosis of maple syrup urine disease owing to ingestion of herbal tea. N Engl J Med 1999;341:769.. PubMed
  8. Abdo MS, al-Kafawi AA. Experimental studies on the effect of Trigonella foenum-graecum (abstract). Planta Med 1969;17:14-8.
  9. Gupta A, Gupta R, Lal B. Effect of Trigonella foenum-graecum (fenugreek) seeds on glycaemic control and insulin resistance in type 2 diabetes mellitus: a double blind placebo controlled study. J Assoc Physicians India 2001;49:1057-61.
  10. Gabay MP. Galactogogues: medications that induce lactation. J Hum Lact 2002;18:274-9. PubMed
  11. Chevassus H, Gaillard JB, Farret A, et al. A fenugreek seed extract selectively reduces spontaneous fat intake in overweight subjects. Eur J Clin Pharmacol 2010;66(5):449-55. PubMed
  12. Turkyilmaz C, Onal E, Hirfanoglu IM, et al. The effect of galactagogue herbal tea on breast milk production and short-term catch-up of birth weight in the first week of life. J Altern Complement Med 2011;17(2):139-42. PubMed
  13. Swafford S, Berens P. Effect of fenugreek on breast milk volume. Abstract presented at: 5th International Meeting of the Academy of Breastfeeding Medicine; September 11-13,2000, Tucson, Arizona.
  14. Abdel-Barry, J. A., Abdel-Hassan, I. A., Jawad, A. M., and al Hakiem, M. H. Hypoglycaemic effect of aqueous extract of the leaves of Trigonella foenum-graecum in healthy volunteers. East Mediterr.Health J 2000;6(1):83-88. DOI
  15. Parvizpur, A., Ahmadiani, A., and Kamalinejad, M. Probable role of spinal purinoceptors in the analgesic effect of Trigonella foenum (TFG) leaves extract. J Ethnopharmacol 3-8-2006;104(1-2):108-112. PubMed
  16. Mora, A., Herrrera, A., Lopez, C., Dahbi, G., Mamani, R., Pita, J. M., Alonso, M. P., Llovo, J., Bernardez, M. I., Blanco, J. E., Blanco, M., and Blanco, J. Characteristics of the Shiga-toxin-producing enteroaggregative Escherichia coli O104:H4 German ou
  17. Blanco, J. [Stx2a-producing enteroaggregative Escherichia coli O104:H4-ST678. Microbiological diagnostic already, for this and other STEC/VTEC serotypes!]. Enferm.Infecc.Microbiol.Clin. 2012;30(2):84-89.
  18. Beutin, L. and Martin, A. Outbreak of Shiga toxin-producing Escherichia coli (STEC) O104:H4 infection in Germany causes a paradigm shift with regard to human pathogenicity of STEC strains. J Food Prot. 2012;75(2):408-418. PubMed
  19. King LA, Nogareda F, Weill FX, Mariani-Kurkdjian P, Loukiadis E, Gault G, Jourdan-DaSilva N, Bingen E, Macé M, Thevenot D, Ong N, Castor C, Noël H, Van Cauteren D, Charron M, Vaillant V, Aldabe B, Goulet V, Delmas G, Couturier E, Le Strat Y, Combe C, Delm
  20. Reeder C, Legrand A, O'Connor-Von SK. The Effect of Fenugreek on Milk Production and Prolactin Levels in Mothers of Preterm Infants. Clinical Lactation 2013;4(4):159-165. DOI
  21. Al-Jenoobi FI, Ahad A, Mahrous GM, Al-Mohizea AM, AlKharfy KM, Al-Suwayeh SA. Effects of fenugreek, garden cress, and black seed on theophylline pharmacokinetics in beagle dogs. Pharm Biol 2015;53(2):296-300. PubMed
  22. Rao A, Steels E, Inder WJ, Abraham S, Vitetta L. Testofen, a specialised Trigonella foenum-graecum seed extract reduces age-related symptoms of androgen decrease, increases testosterone levels and improves sexual function in healthy aging males in a doubl
  23. Steels E, Rao A, Vitetta L. Physiological aspects of male libido enhanced by standardized Trigonella foenum-graecum extract and mineral formulation. Phytother Res. 2011 Sep;25(9):1294-300.
  24. Gong J, Fang K, Dong H, Wang D, Hu M, Lu F. Effect of fenugreek on hyperglycaemia and hyperlipidemia in diabetes and prediabetes: A meta-analysis. J Ethnopharmacol. 2016 Dec 24;194:260-268. PubMed
  25. Ouzir M, El Bairi K, Amzazi S. Toxicological properties of fenugreek (Trigonella foenum graecum). Food Chem Toxicol. 2016 Oct;96:145-54. PubMed
  26. Khodamoradi K, Khosropanah MH, Ayati Z, et al. The Effects of Fenugreek on Cardiometabolic Risk Factors in Adults: A Systematic Review and Meta-analysis. Complement Ther Med. 2020;52:102416. PubMed
  27. Alkharfy K, Jan B, Alotaibi K, et al. Clopidogrel-herb Interactions: A Pharmacokinetic and Pharmacodynamic Assessment in a Rat Model. Curr Drug Metab 2021;22(12):969-977. PubMed
  28. Bin Jardan YA, Ahad A, Raish M, Alam MA, Al-Mohizea AM, Al-Jenoobi FI. Effects of garden cress, fenugreek and black seed on the pharmacodynamics of metoprolol: an herb-drug interaction study in rats with hypertension. Pharm Biol 2021;59(1):1088-1097. PubMed
  29. Al-Mohizea AM, Ahad A, El-Maghraby GM, et al. Effects of Nigella sativa, Lepidium sativum and Trigonella foenum-graecum on sildenafil disposition in beagle dogs. Eur J Drug Metab Pharmacokinet. 2015;40(2):219-24. PubMed
  30. Alkharfy KM, Al-Jenoobi FI, Al-Mohizea AM, et al. Effects of Lepidium sativum, Nigella sativa and Trigonella foenum-graceum on phenytoin pharmacokinetics in beagle dogs. Phytother Res. 2013;27(12):1800-4.

See these in context on the Fenugreek monograph →

Shiitake Mushroom 67 references
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  2. Hanada K, Hashimoto I. Flagellate mushroom (Shiitake) dermatitis and photosensitivity. Dermatol 1998;197:255-7. PubMed
  3. Levy AM, Kita H, Phillips SF, et al. Eosinophilia and gastrointestinal symptoms after ingestion of shiitake mushrooms. J Allergy Clin Immunol 1998;101:613-20. PubMed
  4. Murakami M, Kawabe K, Hosoi Y, et al. Decreased pulmonary perfusion in hypersensitivity pneumonitis caused by Shiitake mushroom spores. J Intern Med 1997;241:85-8. PubMed
  5. Matsui S, Nakazawa T, Umegae Y, Mori M. Hypersensitivity pneumonitis induced by Shiitake mushroom spores. Intern Med 1992;31:1204-6.
  6. Nakamura T. Shiitake (Lentinus edodes) dermatitis. Contact Dermatitis 1992;27:65-70.
  7. Ueda A, Obama K, Aoyama K, et al. Allergic contact dermatitis in shiitake (Lentinus edodes (Berk) Sing) growers. Contact Dermatitis 1992;26:228-33.
  8. Burikhanov, R. B., Wakame, K., Igarashi, Y., Wang, S., and Matsuzaki, S. Suppressive effect of active hexose correlated compound (AHCC) on thymic apoptosis induced by dexamethasone in the rat. Endocr.Regul. 2000;34(4):181-188.
  9. Gao, Y., Zhang, D., Sun, B., Fujii, H., Kosuna, K., and Yin, Z. Active hexose correlated compound enhances tumor surveillance through regulating both innate and adaptive immune responses. Cancer Immunol.Immunother. 2006;55(10):1258-1266. PubMed
  10. Ritz, B. W., Nogusa, S., Ackerman, E. A., and Gardner, E. M. Supplementation with active hexose correlated compound increases the innate immune response of young mice to primary influenza infection. J Nutr. 2006;136(11):2868-2873. PubMed
  11. Aviles, H., O'Donnell, P., Sun, B., and Sonnenfeld, G. Active hexose correlated compound (AHCC) enhances resistance to infection in a mouse model of surgical wound infection. Surg.Infect.(Larchmt.) 2006;7(6):527-535. PubMed
  12. Spierings, E. L., Fujii, H., Sun, B., and Walshe, T. A Phase I study of the safety of the nutritional supplement, active hexose correlated compound, AHCC, in healthy volunteers. J Nutr Sci Vitaminol.(Tokyo) 2007;53(6):536-539. PubMed
  13. Aviles, H., O'Donnell, P., Orshal, J., Fujii, H., Sun, B., and Sonnenfeld, G. Active hexose correlated compound activates immune function to decrease bacterial load in a murine model of intramuscular infection. Am J Surg. 2008;195(4):537-545. PubMed
  14. Ritz, B. W. Supplementation with active hexose correlated compound increases survival following infectious challenge in mice. Nutr.Rev. 2008;66(9):526-531. PubMed
  15. Terakawa, N., Matsui, Y., Satoi, S., Yanagimoto, H., Takahashi, K., Yamamoto, T., Yamao, J., Takai, S., Kwon, A. H., and Kamiyama, Y. Immunological effect of active hexose correlated compound (AHCC) in healthy volunteers: a double-blind, placebo-controll
  16. Mach, C. M., Fugii, H., Wakame, K., and Smith, J. Evaluation of active hexose correlated compound hepatic metabolism and potential for drug interactions with chemotherapy agents. J Soc Integr.Oncol. 2008;6(3):105-109.
  17. Wang, S., Welte, T., Fang, H., Chang, G. J., Born, W. K., O'Brien, R. L., Sun, B., Fujii, H., Kosuna, K., and Wang, T. Oral administration of active hexose correlated compound enhances host resistance to West Nile encephalitis in mice. J Nutr. 2009;139(3 PubMed
  18. Sumiyoshi, Y., Hashine, K., Kakehi, Y., Yoshimura, K., Satou, T., Kuruma, H., Namiki, S., and Shinohara, N. Dietary administration of mushroom mycelium extracts in patients with early stage prostate cancers managed expectantly: a phase II study. Jpn.J Cl PubMed
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  20. Lee, W. W., Lee, N., Fujii, H., and Kang, I. Active Hexose Correlated Compound promotes T helper (Th) 17 and 1 cell responses via inducing IL-1beta production from monocytes in humans. Cell Immunol. 2012;275(1-2):19-23.
  21. Daddaoua, A., Martinez-Plata, E., Ortega-Gonzalez, M., Ocon, B., Aranda, C. J., Zarzuelo, A., Suarez, M. D., de Medina, F. S., and Martinez-Augustin, O. The nutritional supplement Active Hexose Correlated Compound (AHCC) has direct immunomodulatory actio
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See these in context on the Shiitake Mushroom monograph →

Calcium 62 references
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Horsetail 14 references
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Parts of this content are provided by the Therapeutic Research Center, LLC.

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

© 2021 Therapeutic Research Center, LLC

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