Herbal Calcium Formula Ingredients & Drug Interactions
by Christopher's Original Formulas
What is this page for?
First and foremost: checking Herbal Calcium Formula 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
Herbal Calcium Formula is a dietary supplement by Christopher's Original Formulas with 4 active ingredients. Its ingredients are commonly taken for lowering cholesterol, heart and digestive health, soothing itchy or irritated skin.Based on those ingredients, 190 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Horsetail, Nettle, Oatstraw. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Herbal Calcium Formula by Christopher's Original Formulas
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AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Herbal Calcium Formula by Christopher's Original Formulas
Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.
What’s inside
Low disclosure
This formula contains 4 active ingredients: oatstraw, lobelia, nettle, and horsetail, blended together to provide a combination approach to calcium and mineral support. Oatstraw contributes fiber and minerals from the plant; lobelia is a traditional herbal ingredient; nettle leaf supplies additional minerals; and horsetail is included for its mineral content.
The product also contains inactive ingredients listed as a base.
Does it work?
Strong evidence
The evidence is limited. Oatstraw is likely effective for lowering cholesterol and supporting heart health.
For the other ingredients—lobelia, nettle, and horsetail—the data we hold either rates them as insufficient evidence or possibly ineffective. We don't have effectiveness ratings for this product's stated calcium or mineral support purpose, so we can't tell you from our data how well it may work for that.
How safe is it?
Well-documented data
Oatstraw is generally well tolerated; the most common side effects are bloating, flatulence, and abdominal distention, usually mild and temporary when you start. Lobelia carries a caution label for toxicity at higher doses (symptoms include sweating, rapid heart rate, tremors, and in severe cases, dangerous drops in blood pressure).
Nettle is generally well tolerated but may cause constipation or diarrhea. Horsetail should be used short-term only; long-term use carries risks, and crude horsetail can cause thiamine deficiency with prolonged use.
For pregnancy: oatstraw eaten as food is considered likely safe, but concentrated oat supplements are less studied. Lobelia, nettle, and horsetail are all advised against in pregnancy due to lack of safety data or toxicity concerns.
For breastfeeding, the same caution applies to all but oatstraw—safety data for supplement forms is insufficient, so talk with your doctor or pharmacist before use.
Meds to double-check
Moderate interaction found
Before taking this product, double-check with your doctor or pharmacist if you're on any antidiabetes drugs or insulin (oatstraw, nettle, and horsetail may lower blood sugar); any diuretics or water pills (nettle and horsetail); warfarin or other blood thinners (nettle contains vitamin K); lithium for mood (lobelia, nettle, and horsetail may raise lithium levels); or HIV medications like efavirenz or other NRTIs (horsetail may reduce their effectiveness). No interactions are documented for the proprietary blend container itself.
The bottom line
Scorecard at a glanceFormula with limited ingredient disclosure with strong clinical evidence behind its ingredients' uses. Moderate medication interactions have been identified, and safety information is well characterized.
This product combines four herbal ingredients with a history in traditional medicine, though modern evidence for its stated purpose (calcium support) isn't established in our data. The biggest concern is that it interacts with several important medication types—antidiabetes drugs, insulin, blood thinners, lithium, and HIV medications.
If you take any prescription medication, especially for diabetes, blood pressure, blood clotting, mood, or HIV, check your exact drugs with your doctor or pharmacist before starting.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 4 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Apr 25, 2019.
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
General information
Key facts about Herbal Calcium Formula, straight from the product label.
| Brand | Christopher's Original Formulas |
|---|---|
| Barcode (UPC) | 084783498087 |
| Net contents | 2 fl. Oz.; 59 mL |
| Market status | On market |
| Date entered into DSLD | Apr 25, 2019 |
| DSLD ID | 200440 |
| Product type | Botanical |
| Supplement form | Liquid |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years) |
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 Herbal Calcium Formula by Christopher's Original Formulas, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Proprietary Blend | 0 NP | -- |
| Oatstraw | 0 NP | -- |
| Lobelia | 0 NP | -- |
| Nettle | 0 NP | -- |
| Horsetail | 0 NP | -- |
Other ingredients: A base of
Tap any ingredient to jump to its full detail below.
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.
Suggested/Recommended/Usage/Directions
Directions: As a dietary supplement take two droppersful three times a day, or as directed by your health care professional.
Storage
Store in a cool dry place.
Precautions
Warning: Do not use during pregnancy or give to small children except as directed by your health care professional
Warning: Do not use during pregnancy or give to small children except as directed by your health care professional
Brand IP Statement(s)
2010 Wholistic Botanicals L.L.C All Rights Reserved
John R. Christopher
FDA Statement of Identity
Dietary Supplement
Formulation
No added fillers or chemicals.
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 disease.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Herbal Calcium Formula by Christopher's Original Formulas label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Herbal Calcium Formula by Christopher's Original Formulas
These are the 4 active ingredients this product is made of. Select any to open its full monograph.
Serving size2 Dropper(s) Dosage formLiquid Servings per container29 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.
Other (inactive) ingredients: A base of. These complete the product’s ingredient list but are not active constituents.
Herbal Calcium Formula by Christopher's Original Formulas Drug Interactions
HelloPharmacist Interaction Report
Herbal Calcium Formula by Christopher's Original Formulas contains four active ingredients—oatstraw, lobelia, nettle, and horsetail—that together have documented interactions with medications.
The most serious concern is lobelia's interaction with lithium: lobelia's diuretic properties may reduce lithium excretion and raise blood levels, requiring a dose adjustment.
Read the full breakdown — every affected drug type, severity by severity
Oatstraw and nettle both interact with antidiabetes drugs and insulin, raising the risk of low blood sugar (hypoglycemia)—a Moderate-severity issue. Nettle and horsetail also interact with diuretic drugs; nettle's vitamin K content may interfere with warfarin (a blood thinner); and horsetail has documented interactions with HIV medications (NRTIs and efavirenz), potentially reducing their effectiveness.
Nettle and horsetail both interact with lithium in ways that could increase lithium levels.
Altogether, these interactions span 190 individual medications. Use the search tool below to check your exact prescriptions before you start this product.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Herbal Calcium Formula?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Herbal Calcium Formula interact with 190 drugs. Click any drug to see the details.
4 of the 4 ingredients in Herbal Calcium Formula interact with drugs. Each result below shows which ingredient is responsible. Horsetail Nettle Oatstraw Lobelia
Abacavir Sulfate, Dolutegravir, LamivudineTriumeq
How Abacavir Sulfate, Dolutegravir, Lamivudine interacts with Herbal Calcium Formula — through 1 ingredient. Tap an ingredient for the detail:
HorsetailNucleoside Reverse Transcriptase Inhibitors (nrtis) Moderate
Interaction Summary
Theoretically, horsetail might decrease the levels and clinical effects of NRTIs.
Read the full Horsetail + Abacavir Sulfate, Dolutegravir, Lamivudine interactionAbacavir, LamivudineEpzicom
How Abacavir, Lamivudine interacts with Herbal Calcium Formula — through 1 ingredient. Tap an ingredient for the detail:
HorsetailNucleoside Reverse Transcriptase Inhibitors (nrtis) Moderate
Interaction Summary
Theoretically, horsetail might decrease the levels and clinical effects of NRTIs.
Read the full Horsetail + Abacavir, Lamivudine interactionAcarboseGlucobay, Prandase, Precose
How Acarbose interacts with Herbal Calcium Formula — through 3 ingredients. Tap an ingredient for the detail:
HorsetailAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full Horsetail + Acarbose interactionNettleAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Read the full Nettle + Acarbose interactionOatstrawAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oats may have additive effects with antidiabetic agents and might increase the risk of hypoglycemia.
Read the full Oatstraw + Acarbose interactionAcetaminophen, Caffeine, PyrilamineMidol Max Strength Menstrual
How Acetaminophen, Caffeine, Pyrilamine interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
NettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Acetaminophen, Caffeine, Pyrilamine interactionHorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Acetaminophen, Caffeine, Pyrilamine interactionAcetaminophen, Pamabrom, PyrilamineMidol Max Strength PMS, Pamprin, Pamprin ES
How Acetaminophen, Pamabrom, Pyrilamine interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
HorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Acetaminophen, Pamabrom, Pyrilamine interactionNettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Acetaminophen, Pamabrom, Pyrilamine interactionAcetazolamideAk-Zol, Diamox
How Acetazolamide interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
NettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Acetazolamide interactionHorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Acetazolamide interactionAcetohexamideDymelor
How Acetohexamide interacts with Herbal Calcium Formula — through 3 ingredients. Tap an ingredient for the detail:
HorsetailAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full Horsetail + Acetohexamide interactionNettleAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Read the full Nettle + Acetohexamide interactionOatstrawAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oats may have additive effects with antidiabetic agents and might increase the risk of hypoglycemia.
Read the full Oatstraw + Acetohexamide interactionAdefovirHepsera
How Adefovir interacts with Herbal Calcium Formula — through 1 ingredient. Tap an ingredient for the detail:
HorsetailNucleoside Reverse Transcriptase Inhibitors (nrtis) Moderate
Interaction Summary
Theoretically, horsetail might decrease the levels and clinical effects of NRTIs.
Read the full Horsetail + Adefovir interactionAlbiglutideTanzeum
How Albiglutide interacts with Herbal Calcium Formula — through 3 ingredients. Tap an ingredient for the detail:
HorsetailAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full Horsetail + Albiglutide interactionNettleAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Read the full Nettle + Albiglutide interactionOatstrawAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oats may have additive effects with antidiabetic agents and might increase the risk of hypoglycemia.
Read the full Oatstraw + Albiglutide interactionAlogliptinNesina
How Alogliptin interacts with Herbal Calcium Formula — through 3 ingredients. Tap an ingredient for the detail:
NettleAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Read the full Nettle + Alogliptin interactionOatstrawAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oats may have additive effects with antidiabetic agents and might increase the risk of hypoglycemia.
Read the full Oatstraw + Alogliptin interactionHorsetailAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full Horsetail + Alogliptin interactionAlogliptin, MetforminKazano
How Alogliptin, Metformin interacts with Herbal Calcium Formula — through 3 ingredients. Tap an ingredient for the detail:
HorsetailAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full Horsetail + Alogliptin, Metformin interactionNettleAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Read the full Nettle + Alogliptin, Metformin interactionOatstrawAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oats may have additive effects with antidiabetic agents and might increase the risk of hypoglycemia.
Read the full Oatstraw + Alogliptin, Metformin interactionAlogliptin, PioglitazoneOseni
How Alogliptin, Pioglitazone interacts with Herbal Calcium Formula — through 3 ingredients. Tap an ingredient for the detail:
NettleAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Read the full Nettle + Alogliptin, Pioglitazone interactionOatstrawAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oats may have additive effects with antidiabetic agents and might increase the risk of hypoglycemia.
Read the full Oatstraw + Alogliptin, Pioglitazone interactionHorsetailAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full Horsetail + Alogliptin, Pioglitazone interactionAmiloride, HydrochlorothiazideAmil-Co, Amilzide, Moduret 25, Moduretic
How Amiloride, Hydrochlorothiazide interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
HorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Amiloride, Hydrochlorothiazide interactionNettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Amiloride, Hydrochlorothiazide interactionAmmonium ChlorideAmmonium Chloride
How Ammonium Chloride interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
NettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Ammonium Chloride interactionHorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Ammonium Chloride interactionAntidiabetes, Dipeptidyl Peptidase-4 (dpp-iv) InhibitorGlyxambi
How Antidiabetes, Dipeptidyl Peptidase-4 (dpp-iv) Inhibitor interacts with Herbal Calcium Formula — through 3 ingredients. Tap an ingredient for the detail:
HorsetailAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full Horsetail + Antidiabetes, Dipeptidyl Peptidase-4 (dpp-iv) Inhibitor interactionNettleAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Read the full Nettle + Antidiabetes, Dipeptidyl Peptidase-4 (dpp-iv) Inhibitor interactionOatstrawAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oats may have additive effects with antidiabetic agents and might increase the risk of hypoglycemia.
Read the full Oatstraw + Antidiabetes, Dipeptidyl Peptidase-4 (dpp-iv) Inhibitor interactionAtenolol, ChlortalidoneAtenixCo, Tenoret 50, Totaretic
How Atenolol, Chlortalidone interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
NettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Atenolol, Chlortalidone interactionHorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Atenolol, Chlortalidone interactionAtenolol, ChlorthalidoneTenoretic
How Atenolol, Chlorthalidone interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
HorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Atenolol, Chlorthalidone interactionNettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Atenolol, Chlorthalidone interactionAzilsartan, ChlorthalidoneEdarbyclor
How Azilsartan, Chlorthalidone interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
NettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Azilsartan, Chlorthalidone interactionHorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Azilsartan, Chlorthalidone interactionBenazepril, HydrochlorothiazideLotensin HCT
How Benazepril, Hydrochlorothiazide interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
HorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Benazepril, Hydrochlorothiazide interactionNettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Benazepril, Hydrochlorothiazide interactionBendroflumethiazideAprinox, Naturetin, Neo-NaClex
How Bendroflumethiazide interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
NettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Bendroflumethiazide interactionHorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Bendroflumethiazide interactionBendroflumethiazide, NadololCorzide
How Bendroflumethiazide, Nadolol interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
HorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Bendroflumethiazide, Nadolol interactionNettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Bendroflumethiazide, Nadolol interactionBendroflumethiazide, PotassiumCentyl K, Neo-NaClex-K
How Bendroflumethiazide, Potassium interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
NettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Bendroflumethiazide, Potassium interactionHorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Bendroflumethiazide, Potassium interactionBendroflumethiazide, Rauwolfia SerpentinaRauzide
How Bendroflumethiazide, Rauwolfia Serpentina interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
HorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Bendroflumethiazide, Rauwolfia Serpentina interactionNettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Bendroflumethiazide, Rauwolfia Serpentina interactionBenzthiazideExna
How Benzthiazide interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
NettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Benzthiazide interactionHorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Benzthiazide interactionBisoprolol, HydrochlorothiazideZiac
How Bisoprolol, Hydrochlorothiazide interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
HorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Bisoprolol, Hydrochlorothiazide interactionNettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Bisoprolol, Hydrochlorothiazide interactionBumetanideBurinex
How Bumetanide interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
NettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Bumetanide interactionHorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Bumetanide interactionBumetanide, PotassiumBurinex K
How Bumetanide, Potassium interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
HorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Bumetanide, Potassium interactionNettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Bumetanide, Potassium interactionCaffeine, Potassium Salicylate, SalicylamideTrim-Elim
How Caffeine, Potassium Salicylate, Salicylamide interacts with Herbal Calcium Formula — through 2 ingredients. Tap an ingredient for the detail:
NettleDiuretic Drugs Moderate
Interaction Summary
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Read the full Nettle + Caffeine, Potassium Salicylate, Salicylamide interactionHorsetailDiuretic Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Read the full Horsetail + Caffeine, Potassium Salicylate, Salicylamide interactionCanagliflozinInvokana
How Canagliflozin interacts with Herbal Calcium Formula — through 3 ingredients. Tap an ingredient for the detail:
HorsetailAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full Horsetail + Canagliflozin interactionNettleAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Read the full Nettle + Canagliflozin interactionOatstrawAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oats may have additive effects with antidiabetic agents and might increase the risk of hypoglycemia.
Read the full Oatstraw + Canagliflozin interactionCanagliflozin, MetforminInvokamet
How Canagliflozin, Metformin interacts with Herbal Calcium Formula — through 3 ingredients. Tap an ingredient for the detail:
NettleAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Read the full Nettle + Canagliflozin, Metformin interactionOatstrawAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, oats may have additive effects with antidiabetic agents and might increase the risk of hypoglycemia.
Read the full Oatstraw + Canagliflozin, Metformin interactionHorsetailAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking horsetail with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full Horsetail + Canagliflozin, Metformin interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Herbal Calcium Formula 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.
Horsetail
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.
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.
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.
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.
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.
Nettle
Antidiabetes Drugs
Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Clinical research shows that stinging nettle might decrease blood glucose levels in patients with diabetes.
Diuretic Drugs
Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Animal research suggests that the above ground parts and roots of stinging nettle may have a diuretic effect.
Lithium
Theoretically, stinging nettle might reduce excretion and increase levels of lithium.
Animal research suggests that stinging nettle has diuretic and natriuretic properties, which could alter the excretion of lithium. The dose of lithium might need to be decreased.
Warfarin (Coumadin)
There is some concern that stinging nettle might decrease the effects of anticoagulant drugs such as warfarin.
Stinging nettle contains a significant amount of vitamin K. When taken in large quantities, this might interfere with the activity of warfarin.
Oatstraw
Antidiabetes Drugs
Theoretically, oats may have additive effects with antidiabetic agents and might increase the risk of hypoglycemia.
Consuming oats can decrease blood glucose in patients with diabetes. In those who require insulin, taking oats 100 grams daily for 2 days reduces the insulin dose required to achieve metabolic control.
Insulin
Concomitant use of oats and insulin might increase the risk of hypoglycemia.
In patients with insulin-dependent type 2 diabetes, taking oats 100 grams daily for 2 days reduces the insulin dose required to achieve metabolic control.
Lobelia
Lithium
Lobelia is thought to have diuretic properties. Theoretically, due to these potential diuretic effects, lobelia might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.
Brand information
Manufacturer and brand details for Herbal Calcium Formula, from the product label.
Christopher's Original Formulas
See all Christopher's Original Formulas products- Name
- Wholistic Botanicals L.L.C.
- City
- Spanish Fork
- State
- UT
- ZipCode
- 84660
- Phone Number
- 1-800-453-1406
- Web Address
- www.drchristopher.com
Herbal Calcium Formula by Christopher's Original Formulas: Common Questions
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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.
The Full Monographs Behind Herbal Calcium Formula’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Oats
Interacts with 86 drugsOats are a well-studied whole grain whose soluble fiber (beta-glucan) can help lower cholesterol and support heart health when eaten regularly. As a food, oats are safe for most people, and...
Read the full Oats monograph → Herb & supplement monographLobelia
Interacts with 1 drugLobelia is a traditional herb once used for breathing problems and to help people quit smoking, but reliable evidence supporting these uses is lacking. It can be toxic in higher amounts, cau...
Read the full Lobelia monograph → Herb & supplement monographStinging Nettle
Interacts with 164 drugsStinging nettle is a common plant used as food and in traditional medicine, most often for prostate symptoms, allergies, and joint pain. The evidence is mixed and mostly preliminary, so it i...
Read the full Stinging Nettle monograph → Herb & supplement monographHorsetail
Interacts with 188 drugsHorsetail 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 & How We Checked
Herbal Calcium Formula'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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 56 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.
Oats 13 references
- Cooper SG, Tracey EJ. Small-bowel obstruction caused by oat-bran bezoar. N Engl J Med 1989;320:1148-9. DOI
- Pick ME, Hawrysh ZJ, Gee MI, et al. Oat bran concentrate bread products improve long-term control of diabetes: a pilot study. J Am Diet Assoc 1996;96:1254-61. PubMed
- Braaten JT, Scott FW, Wood PJ, et al. High beta-glucan oat bran and oat gum reduce postprandial blood glucose and insulin in subjects with and without type 2 diabetes. Diabet Med 1994;11:312-8.
- Rosario PG, Gerst PH, Prakash K, Albu E. Dentureless distention: oat bran bezoars cause obstruction. J Am Geriatr Soc 1990;38:608. PubMed
- Food and Drug Administration. Food labeling: health claims: oats and coronary heart disease. Fed Regist 1996;61:296-313.
- Foulke J. FDA Allows Whole Oat Foods To Make Health Claim on Reducing the Risk of Heart Disease. FDA Talk Paper. 1997. Available at: http://www.fda.gov/bbs/topics/ANSWERS/ANS00782.html.
- Chandalia M, Garg A, Lutjohann D, et al. Beneficial effects of high dietary fiber intake in patients with type 2 diabetes mellitus. N Engl J Med 2000;342:1392-8. PubMed
- Lembo A, Camilleri M. Chronic constipation. N Engl J Med 2003;349:1360-8. . PubMed
- De Paz Arranz S, Perez Montero A, Remon LZ, Molero MI. Allergic contact urticaria to oatmeal. Allergy 2002;57:1215. . PubMed
- Delgado G, Kleber ME, Krämer BK, et al. Dietary intervention with oatmeal in patients with uncontrolled type 2 diabetes mellitus - A crossover study. Exp Clin Endocrinol Diabetes. 2019;127(9):623-629. PubMed
- Sobhan M, Hojati M, Vafaie SY, Ahmadimoghaddam D, Mohammadi Y, Mehrpooya M. The efficacy of colloidal oatmeal cream 1% as add-on therapy in the management of chronic irritant hand eczema: A double-blind study. Clin Cosmet Investig Dermatol. 2020;13:241-25
- Hou Q, Li Y, Li L, Cheng G, Sun X, Li S, Tian H. The metabolic effects of oats intake in patients with type 2 diabetes: A systematic review and meta-analysis. Nutrients. 2015;7(12):10369-87. PubMed
- González-Afonso M, Cañas JA, Sastre B, et al. A Case of Anaphylaxis After Ingestion of Oats: Research Into New Allergens. J Investig Allergol Clin Immunol 2022;32(6):506-508. PubMed
Lobelia 6 references
- Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
- Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
- McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
- McChargue DE, Collins FL Jr, Cohen LM. Effect of non-nicotinic moist snuff replacement and lobeline on withdrawal symptoms during 48-h smokeless tobacco deprivation. Nicotine Tob Res 2002;4:195-200. PubMed
- Stead LF, Hughes JR. Lobeline for smoking cessation. Cochrane Database Syst Rev 2000;2:CD000124. PubMed
- Plakun, A. L., Ambrus, J., Bross, I., Graham, S., Levin, M. L., and Ross, C. A. Clinical factors in smoking withdrawal: preliminary report. Am J Public Health Nations.Health 1966;56(3):434-441. PubMed
Stinging Nettle 23 references
- Monographs on the medicinal uses of plant drugs. Exeter, UK: European Scientific Co-op Phytother, 1997.
- Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
- The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
- Schulz V, Hansel R, Tyler VE. Rational Phytotherapy: A Physician's Guide to Herbal Medicine. Terry C. Telger, transl. 3rd ed. Berlin, GER: Springer, 1998.
- Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
- Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
- Mittman P. Randomized, double-blind study of freeze-dried Urtica dioica in the treatment of allergic rhinitis. Planta Med 1990;56:44-7.
- Vontobel HP, Herzog R, Rutishauser G, Kres H. [Results of a double-blind study on the effectiveness of ERU (extractum radicis Urticae) capsules in conservative treatment of benign prostatic hyperplasia]. (Abstract). Urologe A 1985;24:49-51.
- Randall C, Randall H, Dobbs F, et al. Randomized controlled trial of nettle sting for treatment of base-of-thumb pain. J R Soc Med 2000;93:305-9. PubMed
- Caliskaner Z, Karaayvaz M, Ozturk S. Misuse of a herb: stinging nettle (Urtica urens) induced severe tongue oedema. Complement Ther Med 2004;12:57-8. PubMed
- Krzeski, T., Kazon, M., Borkowski, A., Witeska, A., and Kuczera, J. Combined extracts of Urtica dioica and Pygeum africanum in the treatment of benign prostatic hyperplasia: double-blind comparison of two doses. Clin Ther 1993;15(6):1011-1020.
- Randall, C., Meethan, K., Randall, H., and Dobbs, F. Nettle sting of Urtica dioica for joint pain--an exploratory study of this complementary therapy. Complement Ther Med 1999;7(3):126-131. PubMed
- Tahri, A., Yamani, S., Legssyer, A., Aziz, M., Mekhfi, H., Bnouham, M., and Ziyyat, A. Acute diuretic, natriuretic and hypotensive effects of a continuous perfusion of aqueous extract of Urtica dioica in the rat. J Ethnopharmacol 2000;73(1-2):95-100. PubMed
- Sahin, M., Yilmaz, H., Gursoy, A., Demirel, A. N., Tutuncu, N. B., and Guvener, N. D. Gynaecomastia in a man and hyperoestrogenism in a woman due to ingestion of nettle (Urtica dioica). N.Z.Med.J. 2007;120(1265):U2803.
- Randall, C., Dickens, A., White, A., Sanders, H., Fox, M., and Campbell, J. Nettle sting for chronic knee pain: a randomised controlled pilot study. Complement Ther.Med. 2008;16(2):66-72. PubMed
- Rayburn, K., Fleischbein, E., Song, J., Allen, B., Kundert, M., Leiter, C., and Bush, T. Stinging nettle cream for osteoarthritis. Altern.Ther.Health Med. 2009;15(4):60-61.
- Oliver, F., Amon, E. U., Breathnach, A., Francis, D. M., Sarathchandra, P., Black, A. K., and Greaves, M. W. Contact urticaria due to the common stinging nettle (Urtica dioica)-- histological, ultrastructural and pharmacological studies. Clin Exp Dermato PubMed
- Kulze, A. and Greaves, M. Contact urticaria caused by stinging nettles. Br.J Dermatol. 1988;119(2):269-270. PubMed
- Patten G. Medicinal plant review: Urtica. Aust J Med Herbalism 1993;5(1):5-13.
- Maor D, Little M. Skin contact with a stinging tree requiring intensive care unit admission. Contact Dermatitis. 2017 Nov;77(5):335-37. PubMed
- Easton L, Vaid S, Nagel AK, Venci JV, Fortuna RJ. Stinging Nettle (Urtica dioica): An Unusual Case of Galactorrhea. Am J Case Rep 2021;22:e933999. PubMed
- Niazi B, Ahmed K, Ahmed M, Ali S, Song K, Elias S. Drug-Induced Liver Injury from Herbal Liver Detoxification Tea. Case Rep Gastroenterol 2022;16(3):612-617. PubMed
- Nnamani I, Tolu-Akinnawo O, Dufera RR, Akintunde A, Maliakkal B. Tinospora cordifolia (Guduchi/Giloy)-Induced Liver Injury: A Case Review. Cureus 2023;15(5):e39793. PubMed
Horsetail 14 references
- Sudan BJ. Seborrhoeic dermatitis induced by nicotine of horsetails (Equisetum arvense L.). Contact Dermatitis 1985;13:201-2.
- Perez Gutierrez RM, Laguna GY, Walkowski A. Diuretic activity of Mexican equisetum. J Ethnopharmacol 1985;14:269-72. PubMed
- Lemus I, Garcia R, Erazo S, et al. Diuretic activity of an Equisetum bogotense tea (Platero herb): evaluation in healthy volunteers. J Ethnopharmacol 1996;54:55-8. PubMed
- Revilla MC, Andrade-Cetto A, Islas S, Wiedenfeld H. Hypoglycemic effect of Equisetum myriochaetum aerial parts on type 2 diabetic patients. J Ethnopharmacol 2002;81:117-20. PubMed
- Tiktinskii, O. L. and Bablumian, I. A. [Therapeutic action of Java tea and field horsetail in uric acid diathesis]. Urol.Nefrol.(Mosk) 1983;3(1):47-50.
- Henderson JA, Evans EV, and McIntosh RA. The antithiamine action of Equisetum. J Amer Vet Med Assoc 1952;120:375-378.
- Carneiro DM, Freire RC, Honório TC, Zoghaib I, Cardoso FF, Tresvenzol LM, de Paula JR, Sousa AL, Jardim PC, da Cunha LC. Randomized, Double-Blind Clinical Trial to Assess the Acute Diuretic Effect of Equisetum arvense (Field Horsetail) in Healthy Voluntee
- Klnçalp S, Ekiz F, Basar Ö, Coban S, Yüksel O. Equisetum arvense (Field Horsetail)-induced liver injury. Eur J Gastroenterol Hepatol. 2012 Feb;24(2):213-4. PubMed
- Ortega García JA, Angulo MG, Sobrino-Najul EJ, Soldin OP, Mira AP, Martínez-Salcedo E, Claudio L. Prenatal exposure of a girl with autism spectrum disorder to 'horsetail' (Equisetum arvense) herbal remedy and alcohol: a case report. J Med Case Rep. 2011 M PubMed
- Cordova E, Morganti L, Rodriguez C. Possible Drug-Herb Interaction between Herbal Supplement Containing Horsetail (Equisetum arvense) and Antiretroviral Drugs. J Int Assoc Provid AIDS Care. 2017;16(1):11-13.
- García Gavilán MD, Moreno García AM, Rosales Zabal JM, Navarro Jarabo JM, Sánchez Cantos A. Case of drug-induced acute pancreatitis produced by horsetail infusions. Rev Esp Enferm Dig. 2017 Apr;109(4):301-304. PubMed
- Vieira GT, de Oliveira TT, Carneiro MAA, et al. Antidiabetic effect of Equisetum giganteum L. extract on alloxan-diabetic rabbit. J Ethnopharmacol. 2020;260:112898. PubMed
- Health Canada. Organism-Equisetum arvense. Available at: http://webprod.hc-sc.gc.ca/nhpid-bdipsn/ingredReq.do?id=6117&lang=eng. Accessed 21-July 2021.
- Bates D, Duong TB, Kheyson S, Moore K. Hyponatremia Secondary to Decreased Oral Intake and SIADH and Possibly Exacerbated by Horsetail (Equisetum arvense). Can J Hosp Pharm 2021;74(4):386-389. PubMed
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