TrueJoint FLX Ingredients & Drug Interactions
by NatureCity
What is this page for?
First and foremost: checking TrueJoint FLX 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
TrueJoint FLX is a dietary supplement by NatureCity with 4 active ingredients. Its ingredients are commonly taken for bone health and osteoporosis, correcting vitamin d deficiency, immune system support.Based on those ingredients, 978 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Vitamin D, ParActin. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against TrueJoint FLX by NatureCity
Ask about any prescription or over-the-counter medication and we check it for interactions with TrueJoint FLX by NatureCity — and tell you which ingredient is responsible.
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 TrueJoint FLX by NatureCity
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
Full disclosure
TrueJoint FLX has four active ingredients. Vitamin D is included to support bone and mineral metabolism.
ParActin is the brand name for andrographis, a plant extract used in joint and inflammatory support. Two other actives — TamaFlex and TendoGuard — are also in the formula, though we don't have detailed information on them in our files.
The capsules also contain inactive ingredients: gelatin, rice flour, stearic acid, silica, and medium chain triglyceride.
Does it work?
Strong evidence
Vitamin D is effective for treating rickets, osteomalacia, renal bone disease, and certain metabolic disorders — conditions where vitamin D deficiency causes bone or mineral problems. For andrographis (ParActin), the evidence is weaker: it's rated possibly effective for inflammatory bowel conditions like ulcerative colitis, sore throat, and osteoarthritis, but the evidence for familial Mediterranean fever is insufficient to rate.
Because this product is marketed as a joint formula, the effectiveness data we hold don't directly address joint health in otherwise healthy people — that evidence isn't in our files.
How safe is it?
Well-documented data
Vitamin D is generally well tolerated at recommended doses, but very high doses taken over time can cause toxicity — symptoms include high blood calcium, bone loss, eye irritation, and vision problems. Andrographis is often well tolerated in the short term, but long-term safety isn't well established.
The most common side effects are stomach upset, nausea, diarrhea, dizziness, headache, fatigue, rash, and itching; serious allergic reactions including anaphylaxis are rare. Andrographis carries enough concern in pregnancy and breastfeeding that the data advises against it during both — vitamin D has no pregnancy or breastfeeding rating in our files, so talk to your doctor about its use if you're pregnant or nursing.
Meds to double-check
Moderate interaction found
Check these medication types before taking TrueJoint FLX: heart rhythm drugs like digoxin or verapamil (Moderate risk from vitamin D), thiazide water pills (Moderate), blood pressure medications (Moderate risk from andrographis), blood thinners like warfarin or aspirin (Moderate), cholesterol drugs like atorvastatin (Moderate), and drugs that suppress your immune system (Moderate). Also mention any aluminum-containing antacids and diabetes drugs like glipizide.
The bottom line
Scorecard at a glanceFully disclosed formula with strong clinical evidence behind its ingredients' uses. Moderate medication interactions have been identified, and safety information is well characterized.
If you take heart rhythm drugs, blood thinners, blood pressure medications, cholesterol drugs, or immune-suppressing drugs, you need to check this product with your pharmacist before starting. The vitamin D dose matters: stay within recommended limits to avoid high blood calcium.
If you're pregnant or breastfeeding, talk to your doctor first.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 2 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Mar 22, 2023.
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 TrueJoint FLX, straight from the product label.
| Brand | NatureCity |
|---|---|
| Barcode (UPC) | 859003007079 |
| Net contents | 120 Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Mar 22, 2023 |
| DSLD ID | 283379 |
| Product type | Other Combinations |
| Supplement form | Capsule |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Gluten Free |
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 TrueJoint FLX by NatureCity, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Vitamin D | 20 mcg, 10 mcg | 100%, 50% |
| TamaFlex | 250 mg, 125 mg | -- |
| TendoGuard | 750 mg, 375 mg | -- |
| ParActin | 300 mg, 150 mg | -- |
Other ingredients: Gelatin, Rice Flour, Stearic Acid, Silica, Medium Chain Triglyceride
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
Suggested Use: Take two (2) capsules twice a day with water (a total of four (4) capsules per day) or as directed by your health care practitioner.
Precautions
Keep out of reach of children
Do not use if seal is broken or missing
Contains egg.
Storage
Store in a cool dry place
Formula
TamaFlex TendoGuard ParActin
FDA Disclaimer Statement
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
Formulation
Gluten Free Non GMO Soy Free
Joint & Muscle Support
Seals/Symbols
Blended & Packaged in the USA
FDA Statement of Identity
Dietary Supplement
Brand IP Statement(s)
TendoGuard is a trademark of Certified Nutraceuticals, Inc. ParActin is a registered trademark of HP Ingredients. TamaFlex is a trademark of NXT USA, Inc. Patents Pending.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
TrueJoint FLX by NatureCity 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 TrueJoint FLX by NatureCity
These are the 4 active ingredients this product is made of. Select any to open its full monograph.
Serving size2 Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.
Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.
Vitamin D
Interacts with715 drugs
Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people,...
Vitamin D monograph & interactionsTamaFlex
TendoGuard
ParActin
Interacts with413 drugs
Andrographis is a bitter Asian herb traditionally used for colds, flu, and infections, and some studies suggest it may ease cold symptoms and shorten...
ParActin monograph & interactionsOther (inactive) ingredients: Gelatin, Rice Flour, Stearic Acid, Silica, Medium Chain Triglyceride. These complete the product’s ingredient list but are not active constituents.
TrueJoint FLX by NatureCity Drug Interactions
HelloPharmacist Interaction Report
TrueJoint FLX contains vitamin D and andrographis (ParActin), both of which have documented interactions with medications.
The most serious concern is vitamin D's interaction with thiazide diuretics, verapamil, and digoxin — all classed as Moderate severity — because high-dose vitamin D can raise blood calcium levels (hypercalcemia), which may reduce how well heart rhythm drugs work or increase the risk of dangerous heartbeat problems. Vitamin D also interacts with blood thinners (anticoagulants) like warfarin, atorvastatin (a cholesterol drug), and aluminum-containing products, again at Moderate severity and again centered on the risk of high blood calcium or reduced drug absorption.
Read the full breakdown — every affected drug type, severity by severity
Andrographis (ParActin) has its own Moderate interactions with blood pressure medications, blood thinners, and drugs that suppress the immune system — it may lower blood pressure further, increase bleeding risk, or interfere with immunosuppression. It also carries Minor interactions with the arthritis drug etoricoxib and the diabetes drug glipizide.
Additionally, vitamin D may induce liver enzymes (CYP3A4) that metabolize many drugs, a Minor interaction.
We could not check two other ingredients — TamaFlex and TendoGuard — because we hold no data for them.
Altogether, these interactions span 964 individual medications. Before you start this product, use the medication checker on this page to look up your exact prescriptions.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against TrueJoint FLX?
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 TrueJoint FLX interact with 978 drugs. Click any drug to see the details.
2 of the 4 ingredients in TrueJoint FLX interact with drugs. Each result below shows which ingredient is responsible. Vitamin D ParActin
6-mercaptopurinePurinethol
How 6-mercaptopurine interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinImmunosuppressants Moderate
Interaction Summary
Theoretically, andrographis might interfere with the effects of immunosuppressive drugs.
Read the full Paractin + 6-mercaptopurine interactionAbciximabReoPro
How Abciximab interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Read the full Paractin + Abciximab interactionAbrocitinibCibinqo
How Abrocitinib interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinAnticoagulant/antiplatelet Drugs, Immunosuppressants Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Read the full Paractin + Abrocitinib interactionAcebutololRhotral, Sectral
How Acebutolol interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinAntihypertensive Drugs Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of hypotension when used with antihypertensive drugs.
Read the full Paractin + Acebutolol interactionAcenocoumarolSintrom
How Acenocoumarol interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Read the full Paractin + Acenocoumarol interactionAcetaminophen, AspirinGemnisyn
How Acetaminophen, Aspirin interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Read the full Paractin + Acetaminophen, Aspirin interactionAcetaminophen, Aspirin, CaffeineExcedrin, Excedrin Extra Strength, Excedrin Migraine
How Acetaminophen, Aspirin, Caffeine interacts with TrueJoint FLX — through 2 ingredients. Tap an ingredient for the detail:
ParactinAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Read the full Paractin + Acetaminophen, Aspirin, Caffeine interactionVitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Aspirin, Caffeine interactionAcetaminophen, IbuprofenCombogesic
How Acetaminophen, Ibuprofen interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Read the full Paractin + Acetaminophen, Ibuprofen interactionAcetazolamideAk-Zol, Diamox
How Acetazolamide interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinAntihypertensive Drugs Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of hypotension when used with antihypertensive drugs.
Read the full Paractin + Acetazolamide interactionAcetylsalicylic AcidEntrophen
How Acetylsalicylic Acid interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Read the full Paractin + Acetylsalicylic Acid interactionAdalimumabHumira
How Adalimumab interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinImmunosuppressants Moderate
Interaction Summary
Theoretically, andrographis might interfere with the effects of immunosuppressive drugs.
Read the full Paractin + Adalimumab interactionAdalimumab-adazHyrimoz
How Adalimumab-adaz interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinImmunosuppressants Moderate
Interaction Summary
Theoretically, andrographis might interfere with the effects of immunosuppressive drugs.
Read the full Paractin + Adalimumab-adaz interactionAdalimumab-adbmCyltezo
How Adalimumab-adbm interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinImmunosuppressants Moderate
Interaction Summary
Theoretically, andrographis might interfere with the effects of immunosuppressive drugs.
Read the full Paractin + Adalimumab-adbm interactionAdalimumab-afzbAbrilada
How Adalimumab-afzb interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinImmunosuppressants Moderate
Interaction Summary
Theoretically, andrographis might interfere with the effects of immunosuppressive drugs.
Read the full Paractin + Adalimumab-afzb interactionAdalimumab-attoAmjevita
How Adalimumab-atto interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinImmunosuppressants Moderate
Interaction Summary
Theoretically, andrographis might interfere with the effects of immunosuppressive drugs.
Read the full Paractin + Adalimumab-atto interactionAdalimumab-bwwdHadlima
How Adalimumab-bwwd interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinImmunosuppressants Moderate
Interaction Summary
Theoretically, andrographis might interfere with the effects of immunosuppressive drugs.
Read the full Paractin + Adalimumab-bwwd interactionAdalimumab-fkjpHulio
How Adalimumab-fkjp interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinImmunosuppressants Moderate
Interaction Summary
Theoretically, andrographis might interfere with the effects of immunosuppressive drugs.
Read the full Paractin + Adalimumab-fkjp interactionAlefaceptAmevive
How Alefacept interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinImmunosuppressants Moderate
Interaction Summary
Theoretically, andrographis might interfere with the effects of immunosuppressive drugs.
Read the full Paractin + Alefacept interactionAlemtuzumabCampath
How Alemtuzumab interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinImmunosuppressants Moderate
Interaction Summary
Theoretically, andrographis might interfere with the effects of immunosuppressive drugs.
Read the full Paractin + Alemtuzumab interactionAlginic Acid, Aluminum HydroxideRafton
How Alginic Acid, Aluminum Hydroxide interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DAluminum Moderate
Interaction Summary
Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
Read the full Vitamin D + Alginic Acid, Aluminum Hydroxide interactionAliskirenTekturna
How Aliskiren interacts with TrueJoint FLX — through 2 ingredients. Tap an ingredient for the detail:
ParactinAntihypertensive Drugs Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of hypotension when used with antihypertensive drugs.
Read the full Paractin + Aliskiren interactionVitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Aliskiren interactionAlteplase, TpaActilyse, Activase
How Alteplase, Tpa interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
ParactinAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Read the full Paractin + Alteplase, Tpa interactionAluminum Acetate, Benzethonium ChlorideBuro-Sol Otic Solution
How Aluminum Acetate, Benzethonium Chloride interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DAluminum Moderate
Interaction Summary
Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
Read the full Vitamin D + Aluminum Acetate, Benzethonium Chloride interactionAluminum ChlorideAluminum Chloride, Anhydrol Forte, Driclor, Drysol
How Aluminum Chloride interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DAluminum Moderate
Interaction Summary
Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
Read the full Vitamin D + Aluminum Chloride interactionAluminum HydroxideAlu-Cap, Amphojel, Gaviscon
How Aluminum Hydroxide interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DAluminum Moderate
Interaction Summary
Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
Read the full Vitamin D + Aluminum Hydroxide interactionAluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium HydroxideAscriptin Codeine #2
How Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interacts with TrueJoint FLX — through 2 ingredients. Tap an ingredient for the detail:
Vitamin DAluminum Moderate
Interaction Summary
Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
Read the full Vitamin D + Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interactionParactinAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Read the full Paractin + Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide interactionAluminum Hydroxide, Aspirin, Magnesium HydroxideAscriptin
How Aluminum Hydroxide, Aspirin, Magnesium Hydroxide interacts with TrueJoint FLX — through 2 ingredients. Tap an ingredient for the detail:
ParactinAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, andrographis might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Read the full Paractin + Aluminum Hydroxide, Aspirin, Magnesium Hydroxide interactionVitamin DAluminum Moderate
Interaction Summary
Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
Read the full Vitamin D + Aluminum Hydroxide, Aspirin, Magnesium Hydroxide interactionAluminum Hydroxide, Magnesium Hydroxide (otc Drug)Maalox, Mucogel
How Aluminum Hydroxide, Magnesium Hydroxide (otc Drug) interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DAluminum Moderate
Interaction Summary
Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
Read the full Vitamin D + Aluminum Hydroxide, Magnesium Hydroxide (otc Drug) interactionAluminum Hydroxide, Magnesium Hydroxide, Simethicone (otc Drug)Mylanta
How Aluminum Hydroxide, Magnesium Hydroxide, Simethicone (otc Drug) interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DAluminum Moderate
Interaction Summary
Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
Read the full Vitamin D + Aluminum Hydroxide, Magnesium Hydroxide, Simethicone (otc Drug) interactionAluminum, CalciumDomeboro
How Aluminum, Calcium interacts with TrueJoint FLX — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DAluminum Moderate
Interaction Summary
Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
Read the full Vitamin D + Aluminum, Calcium interactionEach ingredient & the kinds of drugs it affects
For each ingredient in TrueJoint FLX 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.
Vitamin D
Aluminum
Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
The protein that transports calcium across the intestinal wall can also bind and transport aluminum. This protein is stimulated by vitamin D, which may therefore increase aluminum absorption. This mechanism may contribute to increased aluminum levels and toxicity in people with renal failure, when they take vitamin D and aluminum-containing phosphate binders chronically.
Atorvastatin (Lipitor)
Vitamin D might reduce absorption of atorvastatin.
A small, low-quality clinical study shows that taking vitamin D reduces levels of atorvastatin and its active metabolites by up to 55%. However, while atorvastatin levels decreased, total cholesterol, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol levels did not substantially change. Atorvastatin is metabolized in the gut by CYP3A4 enzymes, and researchers theorized that vitamin D might induce CYP3A4, causing reduced levels of atorvastatin. However, this proposed mechanism was not specifically studied.
Calcipotriene (Dovonex)
Taking calcipotriene with vitamin D increases 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 vitamin D supplements might increase the risk of hypercalcemia.
Digoxin (Lanoxin)
Theoretically, hypercalcemia induced by high-dose vitamin D can increase the risk of arrhythmia from digoxin.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and digoxin concurrently.
Diltiazem (Cardizem, Others)
Theoretically, hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of diltiazem for arrhythmia.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically this could also occur with diltiazem. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and diltiazem concurrently.
Thiazide Diuretics
Theoretically, taking thiazide diuretics and high-dose vitamin D can increase the risk of hypercalcemia.
Thiazide diuretics decrease urinary calcium excretion, which could lead to hypercalcemia if vitamin D supplements are taken concurrently. This has been reported in people being treated with vitamin D for hypoparathyroidism, and also in elderly people with normal parathyroid function who were taking a thiazide, vitamin D, and calcium-containing antacids daily.
Verapamil (Calan, Others)
Hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of verapamil for arrhythmia.
Hypercalcemia due to high doses of vitamin D can reduce the effectiveness of verapamil in atrial fibrillation. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and verapamil concurrently.
Cytochrome P450 3A4 (Cyp3A4) Substrates
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
There is some concern that vitamin D might induce CYP3A4. In vitro research suggests that vitamin D induces CYP3A4 transcription. Additionally, observational research has found that increased UV light exposure and serum vitamin D levels are associated with decreased serum levels of CYP3A4 substrates such as tacrolimus and sirolimus, while no association between UV light exposure or vitamin D levels and levels of mycophenolic acid, a non-CYP3A4 substrate, was found. A small, low-quality clinical study shows that taking vitamin D reduces levels of the CYP3A4 substrate atorvastatin and its active metabolites by up to 55%; however, the clinical effects of atorvastatin were not reduced. While researchers theorized that vitamin D might induce CYP3A4, this proposed mechanism was not specifically studied.
ParActin
Anticoagulant/Antiplatelet Drugs
Theoretically, andrographis might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Animal and laboratory studies suggest that andrographis has antiplatelet effects.
Antihypertensive Drugs
Theoretically, andrographis might increase the risk of hypotension when used with antihypertensive drugs.
Animal research suggests that andrographis has hypotensive effects.
Immunosuppressants
Theoretically, andrographis might interfere with the effects of immunosuppressive drugs.
Laboratory research suggests that andrographolide has immunostimulant activity.
Celecoxib (Celebrex)
Theoretically, andrographis extract might increase the maximum concentration and time to peak concentration of celecoxib. The clinical significance of these changes is unclear.
Animal research suggests that andrographis extract taken orally increases the maximum concentration and time to peak concentration of celecoxib but does not appear to impact the area under the curve.
Etoricoxib (Arcoxia)
Theoretically, andrographis might decrease the absorption of etoricoxib, although the clinical significance is unclear.
Animal research shows that andrographis extract, or the constituent andrographolide, taken orally with etoricoxib decreases the bioavailability of etoricoxib. However, this reduced bioavailability is not correlated with a reduction in the anti-inflammatory effects of etoricoxib in arthritic mice models. The clinical significance of this interaction is unclear.
Glipizide (Glucotrol)
Theoretically, andrographis extract might increase the maximum concentration and area under the curve of glipizide; however, opposite effects are seen with the constituent, andrographolide. The clinical significance of this interaction is unclear.
Animal research suggests that andrographis extract taken orally with glipizide in diabetes-induced rats increases the maximum concentration and area under the curve of glipizide. However, the opposite effect is seen with the constituent, andrographolide, in which the maximum concentration and area under the curve are decreased when taken with glipizide.
Brand information
Manufacturer and brand details for TrueJoint FLX, from the product label.
TrueJoint FLX by NatureCity: Common Questions
Does TrueJoint FLX by NatureCity interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Can I take this if I'm on a blood thinner like warfarin?
Is there vitamin D in this product, and how much?
Can I take this while pregnant?
What is andrographis and what is it for?
What are the most common side effects?
Can I take this long-term?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if TrueJoint FLX is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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 TrueJoint FLX’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Vitamin D
Interacts with 715 drugsVitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people, especially those with low sun exposure,...
Read the full Vitamin D monograph → Herb & supplement monographAndrographis
Interacts with 413 drugsAndrographis is a bitter Asian herb traditionally used for colds, flu, and infections, and some studies suggest it may ease cold symptoms and shorten how long they last. The evidence is limi...
Read the full Andrographis monograph →Sources & How We Checked
TrueJoint FLX'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 52 references behind this product’s interaction data
Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.
Vitamin D 26 references
- McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
- Tatro DS, ed. Drug Interactions Facts. Facts and Comparisons Inc., St. Louis, MO. 1999.
- Koutkia P, Chen TC, Holick MF. Vitamin D intoxication associated with an over-the-counter supplement. N Engl J Med 2001;345:66-7. PubMed
- Bar-Or D, Yoel G. Calcium and calciferol antagonize effect of verapamil in atrial fibrillation. Br Med J 1981;282:1585-6.
- Demontis R, Leflon A, Fournier A, et al. 1 alpha(OH) vitamin D3 increases plasma aluminum in hemodialyzed patients taking AI(OH)3. Clin Nephrol 1986;26:146-9.
- Crowe M, Wollner L, Griffiths RA. Hypercalcemia following vitamin D and thiazide therapy in the elderly. Practitioner 1984;228:312-3.
- Parfitt AM. Thiazide-induced hypercalcemia in vitamin D-treated hypoparathyroidism. Ann Intern Med 1972;77:557-63. PubMed
- Thiazide diuretics and the risk of osteoporosis. Pharmacist's Letter/Prescriber's Letter 2003;19(11):191105.
- Moon J. The role of vitamin D in toxic metal absorption. J Am Coll Nutr 1994;13:559-64.
- Demontis R, Reissi D, Noel C, et al. Indirect clinical evidence that 1alphaOH vitamin D<SUB>3</SUB> increases the intestinal absorption of aluminum. Clin Nephrol 1989;31:123-7.
- Adler AJ, Berlyne GM. Duodenal aluminum absorption in the rat: effect of vitamin D. Am J Physiol 1985;249:G209-13. PubMed
- Schwartz JB. Effects of vitamin D supplementation in atorvastatin-treated patients: A new drug interaction with an unexpected consequence. Clin Pharmacol Ther 2009;85:198-203. PubMed
- Dietary reference intakes for calcium and vitamin D. Institute of Medicine, November 30, 2010. Available at: http://www.iom.edu/~/media/Files/Report%20Files/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D/Vitamin%20D%20and%20Calcium%202010%20Repo
- Cox KA, Dunn MA. Aluminum toxicity alters the regulation of calbindin-D28k protein and mRNA expression in chick intestine. J Nutr 2001;131:2007-13. PubMed
- Escribano, J., Balaguer, A., Pagone, F., Feliu, A., and Roque, I. Figuls. Pharmacological interventions for preventing complications in idiopathic hypercalciuria. Cochrane.Database.Syst.Rev. 2009;(1):CD004754. PubMed
- Carlton, S., Clopton, D., and Cappuzzo, K. A. Vitamin D deficiency: appropriate replenishment therapies and the effects of vitamin D toxicity. Consult Pharm 2010;25(3):171-177. PubMed
- Wang, H., Xia, N., Yang, Y., and Peng, D. Q. Influence of vitamin D supplementation on plasma lipid profiles: a meta-analysis of randomized controlled trials. Lipids Health Dis. 2012;11:42. PubMed
- Turner AN, Carr Reese P, Fields KS, Anderson J, Ervin M, Davis JA, Fichorova RN, Roberts MW, Klebanoff MA, Jackson RD. A blinded, randomized controlled trial of high-dose vitamin D supplementation to reduce recurrence of bacterial vaginosis. Am J Obstet G PubMed
- Weiner M, Epstein FH. Signs and symptoms of electrolyte disorders. Yale J Biol Med. 1970;43(2):76-109.
- Lappe J, Watson P, Travers-Gustafson D, Recker R, Garland C, Gorham E, Baggerly K, McDonnell SL. Effect of Vitamin D and Calcium Supplementation on Cancer Incidence in Older Women: A Randomized Clinical Trial. JAMA. 2017 Mar 28;317(12):1234-1243. PubMed
- Roth DE, Leung M, Mesfin E, Qamar H, Watterworth J, Papp E. Vitamin D supplementation during pregnancy: state of the evidence from a systematic review of randomised trials. BMJ. 2017;359:j5237. PubMed
- Murai IH, Fernandes AL, Sales LP, et al. Effect of a single high dose of vitamin D3 on hospital length of stay in patients with moderate to severe COVID-19: A randomized clinical trial. JAMA. 2021.
- Wang Z, Schuetz EG, Xu Y, Thummel KE. Interplay between vitamin D and the drug metabolizing enzyme CYP3A4. J Steroid Biochem Mol Biol 2013;136:54-8. PubMed
- Doyle D, Browne U, Brickley A, Murphy D. Vitamin D-induced hypercalcaemia and acute kidney injury in sarcoidosis. BMJ Case Rep 2023;16(1):e250580. PubMed
- Williamson A, Martineau AR, Sheikh A, Jolliffe D, Griffiths CJ. Vitamin D for the management of asthma. Cochrane Database Syst Rev 2023;2(2):CD011511. PubMed
- Kinesya E, Santoso D, Gde Arya N, et al. Vitamin D as adjuvant therapy for diabetic foot ulcers: Systematic review and meta-analysis approach. Clin Nutr ESPEN 2023;54:137-143. PubMed
Andrographis 26 references
- McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
- Thamlikitkul V, Dechatiwongse T, Theerapong S, et al. Efficacy of Andrographis paniculata, Nees for pharyngotonsillitis in adults. J Med Assoc Thai 1991;74:437-42.
- Zhang CY, Tan BK. Mechanisms of cardiovascular activity of Andrographis paniculata in the anaesthetized rat. J Ethnopharmacol 1997;56:97-101. PubMed
- Zhao HY, Fang WY. Antithrombotic effects of Andrographis paniculata nees in preventing myocardial infarction. Chin Med J (Engl) 1991;104:770-5.
- Amroyan E, Gabrielian E, Panossian A, et al. Inhibitory effect of andrographolide from Andrographis paniculata on PAF-induced platelet aggregation. Phytomedicine 1999;6:27-31. PubMed
- Zhang C, Kuroyangi M, Tan BK. Cardiovascular activity of 14-deoxy-11,12-didehydroandrographolide in the anaesthetised rat and isolated right atria. Pharmacol Res 1998;38:413-7. PubMed
- Puri A, Saxena R, Saxena RP, et al. Immunostimulant agents from Andrographis paniculata. J Nat Prod 1993;56:995-9. PubMed
- Melchoir J, Spasov AA, Ostrovskij OV, et al. Double-blind, placebo-controlled pilot and phase III study of activity of standardized Andrographis paniculata Herba Nees extract fixed combination (Kan Jang) in the treatment of uncomplicated upper-respirator
- Calabrese C, Berman SH, Babish JG, et al. A phase I trial of andrographolide in HIV positive patients and normal volunteers. Phytother Res 2000;14:333-8. PubMed
- Gabrielian ES, Shukarian AK, Goukasova GI, et al. A double blind, placebo-controlled study of Andrographis paniculata fixed combination Kan Jang in the treatment of acute upper respiratory tract infections including sinusitis. Phytomedicine 2002;9:589-97 PubMed
- Poolsup N, Suthisisang C, Prathanturarug S, et al. Andrographis paniculata in the symptomatic treatment of uncomplicated upper respiratory tract infection: systematic review of randomized controlled trials. J Clin Pharm Ther 2004;29:37-45. PubMed
- Coon JT, Ernst E. Andrographis paniculata in the treatment of upper respiratory tract infections: a systematic review of safety and efficacy. Planta Med 2004;70:293-8.
- Kligler, B., Ulbricht, C., Basch, E., Kirkwood, C. D., Abrams, T. R., Miranda, M., Singh Khalsa, K. P., Giles, M., Boon, H., and Woods, J. Andrographis paniculata for the treatment of upper respiratory infection: a systematic review by the natural standa
- Burgos, R. A., Hancke, J. L., Bertoglio, J. C., Aguirre, V., Arriagada, S., Calvo, M., and Caceres, D. D. Efficacy of an Andrographis paniculata composition for the relief of rheumatoid arthritis symptoms: a prospective randomized placebo-controlled tria
- Saxena, R. C., Singh, R., Kumar, P., Yadav, S. C., Negi, M. P., Saxena, V. S., Joshua, A. J., Vijayabalaji, V., Goudar, K. S., Venkateshwarlu, K., and Amit, A. A randomized double blind placebo controlled clinical evaluation of extract of Andrographis pa
- Tang, T., Targan, S. R., Li, Z. S., Xu, C., Byers, V. S., and Sandborn, W. J. Randomised clinical trial: herbal extract HMPL-004 in active ulcerative colitis - a double-blind comparison with sustained release mesalazine. Aliment.Pharmacol Ther 2011;33(2) PubMed
- Sandborn, W. J., Targan, S. R., Byers, V. S., Rutty, D. A., Mu, H., Zhang, X., and Tang, T. Andrographis paniculata extract (HMPL-004) for active ulcerative colitis. Am J Gastroenterol. 2013;108(1):90-98. PubMed
- Melchior, J., Palm, S., and Wikman, G. Controlled clinical study of standardized Andrographis paniculata extract in common cold - a pilot trial. Phytomedicine. 1997;3(4):315-318. PubMed
- Balap A, Atre B, Lohidasan S, et al. Pharmacokinetic and pharmacodynamic herb-drug interaction of Andrographis paniculata (Nees) extract and andrographolide with etoricoxib after oral administration in rats. J Ethnopharmacol. 2016 May 13;183:9-17. PubMed
- Bertoglio JC, Baumgartner M, Palma R, et al. Andrographis paniculata decreases fatigue in patients with relapsing-remitting multiple sclerosis: a 12-month double-blind placebo-controlled pilot study. BMC Neurol. 2016; 16(1):77. PubMed
- Suwankesawong W, Saokaew S, Permsuwan U, et al. Characterization of hypersensitivity reactions reported among Andrographis paniculata users in Thailand using Health Product Vigilance Center (HPVC) database. BMC Complement Altern Med. 2014; 14:515. PubMed
- Ciampi E, Uribe-San-Martin R, Cárcamo C, et al. Efficacy of andrographolide in not active progressive multiple sclerosis: a prospective exploratory double-blind, parallel-group, randomized, placebo-controlled trial. BMC Neurol 2020;20(1):173. PubMed
- Worakunphanich W, Thavorncharoensap M, Youngkong S, Thadanipon K, Thakkinstian A. Safety of Andrographis paniculata: A systematic review and meta-analysis. Pharmacoepidemiol Drug Saf 2021;30(6):727-739.
- More SJ, Tandulwadkar SS, Balap AR, Lohidasan S, Sinnathambi A, Mahadik KR. Effect of Andrographis paniculata extract and Andrographolide on the pharmacokinetics of Aceclofenac and Celecoxib in rats. Futur J Pharm Sci. 2023;9(1):1. PubMed
- Sundhani E, Nugroho AE, Nurrochmad A, Puspitasari I, Amalia Prihati D, Lukitaningsih E. Pharmacokinetic Herb-Drug Interactions of Glipizide with Andrographis paniculata (Burm. f.) and Andrographolide in Normal and Diabetic Rats by Validated HPLC Method. M PubMed
- Shang YX, Shen C, Stub T, et al. Adverse Effects of Andrographolide Derivative Medications Compared to the Safe use of Herbal Preparations of Andrographis paniculata: Results of a Systematic Review and Meta-Analysis of Clinical Studies. Front Pharmacol 20 PubMed
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
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