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Dietary supplement

TrueSlim Ingredients & Drug Interactions

by NatureCity

TrueSlim label
See full label image
Capsule Category: Botanical
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 TrueSlim 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

TrueSlim is a dietary supplement by NatureCity with 1 active ingredient. Its ingredients are commonly taken for vitamin c source, digestive upset, stress and relaxation (aromatherapy).Based on those ingredients, 246 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Morosil Sicilian Red Orange Fruit Extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against TrueSlim by NatureCity

Ask about any prescription or over-the-counter medication and we check it for interactions with TrueSlim by NatureCity — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of TrueSlim 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.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

TrueSlim contains one active ingredient: Morosil Sicilian Red Orange Fruit Extract, a concentrated form of red orange fruit. The capsule also includes several inactive ingredients—hypromellose, rice flour, stearic acid, and rice hull concentrate—which serve as the capsule shell and binding materials but play no active role in the product.

Does it work?

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

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use — see Sweet Orange's own graded uses on its monograph.

Why this rating?
  • The label markets this product for: weight management support.
  • We looked for evidence on: Obesity, weight loss, metabolic support, body composition.
  • The closest evidence on file: Sweet Orange is rated "Insufficient Reliable Evidence To Rate" for Obesity (Natural Medicines).

The evidence we hold does not establish that Morosil Red Orange Extract is effective for any condition. The ingredient has been studied for pre-procedural anxiety, asthma, prostate cancer, common cold, constipation, and depression, but in each case the data is insufficient to rate it as reliable.

If you're considering this product for one of those purposes, the science hasn't settled the question yet.

The evidence, ingredient by ingredient Sweet Orange

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

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

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Sweet orange fruit itself is well tolerated as food for most people, but this product contains a concentrated extract—and concentrated orange extracts and oils have not been studied extensively. The facts advise caution with supplements in this concentrated form.

There have been reports of intestinal cramping in children after eating large amounts of orange peel. During pregnancy and lactation, the data rates this ingredient as likely safe, though remember that applies to the fruit itself rather than a concentrated extract.

Side effects, ingredient by ingredient Sweet Orange

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Sweet Orange.
  • The most serious interaction on file is rated Major.
  • For scale: 246 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 you take this product, double-check with your pharmacist if you're on pravastatin (a cholesterol drug), celiprolol (a heart medication), or ivermectin (an antiparasitic)—all of which interact at Major severity. Also verify any OATP substrates, P-glycoprotein substrates, quinolone antibiotics, and fexofenadine (an allergy medication) with your pharmacist.

The extract is derived from sweet orange, so any medication your doctor has flagged as problematic with orange juice warrants the same caution.

Check your own medication Run your meds through the checker above

The bottom line

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

TrueSlim is a single-ingredient product that carries serious risks if you take certain heart, cholesterol, or allergy medications—or any drug that depends on intestinal transporters to be absorbed. If you take any prescription medication, check it against the list on this page before starting.

Talk to your pharmacist, especially if you're on pravastatin, celiprolol, ivermectin, or fexofenadine.

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

Assessment coverage: 1 of 1 active ingredient 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

At a glance

General information

Key facts about TrueSlim, straight from the product label.

Brand NatureCity
Barcode (UPC) 859003007345
Net contents 30 Veggie Capsule(s)
Market status On market
Date entered into DSLD Mar 22, 2023
DSLD ID 283360
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for TrueSlim by NatureCity, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
30
UPC/BARCODE
859003007345
IngredientAmount% DV
Morosil Sicilian Red Orange Fruit Extract400 mg--

Other ingredients: Hypromellose, Rice Flour, Stearic Acid, Rice hull concentrate

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.
Suggested/Recommended/Usage/Directions

Suggested Use: Take one (1) capsule a day. If taking two (2) capsules daily is desired or directed by your health care practitioner, take one (1) capsule in the morning and one (1) capsule in the evening.

Formula

TrueSlim helps support weight management goals when used in conjunction with appropriate diet and exercise regimens.

Morosil

Precautions

Keep out of reach of children.

Do not use if seal is broken or missing

Storage

Store in a cool dry place

Formulation

Soy Free Non GMO Gluten Free

Weight Management Support

Seals/Symbols

Blended & Packaged in the USA

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.

FDA Statement of Identity

Dietary Supplement

Brand IP Statement(s)

Morosil is a trademark of Bionap S.r.l

General Statements

To re-order call toll-free: 1-800-593-2563

BPA Free

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

See for yourself

TrueSlim by NatureCity label

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

TrueSlim 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 TrueSlim by NatureCity

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container30 Amounts shown are per serving.

Morosil Sicilian Red Orange Fruit Extract

Interacts with
246 drugs
400 mg per serving

Sweet orange is a common citrus fruit that is a good source of vitamin C, fiber, and antioxidants, and is enjoyed as a food worldwide. Its peel and es...

Morosil Sicilian Red Orange Fruit Extract monograph & interactions

Other (inactive) ingredients: Hypromellose, Rice Flour, Stearic Acid, Rice hull concentrate. These complete the product’s ingredient list but are not active constituents.

Interaction report

TrueSlim by NatureCity Drug Interactions

Want to check YOUR meds against TrueSlim?

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
246Drugs
48 Major 198 Moderate

Ingredients driving the most interactions

Morosil Sicilian Red Orange Fruit Extract 246

Individual Drug Interactions

The ingredients in TrueSlim interact with 246 drugs. Click any drug to see the details.

1 of the 1 ingredient in TrueSlim interact with drugs. Each result below shows which ingredient is responsible. Morosil Sicilian Red Orange Fruit Extract

Each ingredient & the kinds of drugs it affects

For each ingredient in TrueSlim with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Morosil Sicilian Red Orange Fruit Extract7 drug types · 246 drugs

Celiprolol (Celicard)

Consuming sweet orange with celiprolol can decrease oral absorption of celiprolol.
A pharmacokinetic study in healthy volunteers shows that celiprolol levels, after a single dose of 100 mg, are decreased by up to 90% in people who drink sweet orange juice 200 mL three times daily. It's not known if lower consumption of sweet orange juice will have the same effect. Theoretically, this occurs due to short-term inhibition of organic anion transporting polypeptide (OATP). Recommend separating drug administration and consumption of sweet orange by at least 4 hours.

Likelihood Likely Evidence B
Ivermectin (Stromectol, Others)

Consuming sweet orange juice with ivermectin can decrease the oral absorption of ivermectin.
A pharmacokinetic study in healthy volunteers shows that taking ivermectin orally with sweet orange juice 750 mL over 4 hours reduces the bioavailability of ivermectin. This effect does not seem to be related to effects on P-glycoprotein. The effect on ivermectin is more pronounced in males compared to females.

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

Consuming sweet orange juice can decrease oral absorption of OATP substrates. Separate administration by at least 4 hours.
Clinical research shows that consuming sweet orange juice inhibits OATP, which reduces bioavailability of oral drugs that are substrates of OATP. For example, sweet orange juice decreases bioavailability of fexofenadine, a substrate of OATP, by about 72% and of celiprolol, another OATP substrate, by up to 90%. Since sweet orange juice seems to affect OATP for a short time, recommend separating drug administration and consumption of sweet orange juice by at least 4 hours.

Likelihood Likely Evidence B
Pravastatin (Pravachol)

Consuming sweet orange juice with pravastatin can increase the absorption of pravastatin.
A small pharmacokinetic study in healthy volunteers shows that consuming sweet orange juice 800 mL over 3 hours, including before, during, and after taking pravastatin 10 mg, increases pravastatin levels by about 149%, without affecting pravastatin elimination. Theoretically this effect might be due to modulation of organic anion transporting polypeptides (OATPs) by sweet orange juice. Sweet orange juice does not seem to affect simvastatin levels, but it is not known if sweet orange affects any of the other statins.

Likelihood Likely Evidence B
Fexofenadine (Allegra)

Consuming sweet orange juice with fexofenadine can decrease oral absorption of fexofenadine.
Clinical research shows that coadministration of sweet orange juice 1200 mL decreases bioavailability of fexofenadine by about 72%. In an animal model, sweet orange juice decreased bioavailability of fexofenadine by 31%. Fexofenadine manufacturer data indicates that concomitant administration of sweet orange juice and fexofenadine results in larger wheal and flare sizes in research models. This suggests that sweet orange reduces the clinical response to fexofenadine. Theoretically, this occurs due to short-term inhibition of organic anion transporting polypeptide (OATP). Recommend separating drug administration and consumption of sweet orange by at least 4 hours.

Likelihood Likely Evidence B
P-Glycoprotein Substrates

Sweet orange juice seems to modulate P-glycoprotein (P-gp), which might affect the blood levels of P-gp substrates.
Animal and in vitro research suggest that orange juice extract inhibits drug efflux by P-gp, increasing absorption and levels of P-gp substrates. In contrast, pharmacokinetic research in humans shows that drinking large amounts of sweet orange juice decreases absorption and levels of the P-gp substrate celiprolol. This suggests that orange juice actually induces drug efflux by P-gp or affects drug levels by another mechanism such as inhibiting the gut drug transporter called organic anion transporting polypeptide (OATP). Until more is known, sweet orange juice should be used cautiously in people taking P-gp substrates.

Likelihood Possible Evidence B
Quinolone Antibiotics

Calcium-fortified sweet orange juice might reduce quinolone absorption.
Calcium binds to quinolones in the gut. Theoretically, the calcium in certain fortified orange juices can also bind to quinolone antibiotics and reduce their absorption and levels.

Likelihood Possible Evidence D
Morosil Sicilian Red Orange Fruit Extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for TrueSlim, from the product label.

NatureCity

See all NatureCity products
Name
NatureCity
Street Address
990 S. Rogers Circle
City
Boca Raton
State
FL
ZipCode
33487
Phone Number
1-800-593-2563
Web Address
www.naturecity.com
Pharmacist Counseling Corner

TrueSlim by NatureCity: Common Questions

Does TrueSlim by NatureCity interact with any medications?
Yes. Based on its ingredients, TrueSlim has a known interaction with 246 medications, including 48 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
TrueSlim contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is this safe to take if I'm pregnant or breastfeeding?
According to the data we hold, the red orange ingredient is rated likely safe during pregnancy and lactation. That said, this is a concentrated extract rather than whole fruit, and concentrated extracts haven't been studied as thoroughly. Talk to your doctor or pharmacist about whether it's right for your situation.
Does TrueSlim actually work for weight loss or any health condition?
The evidence we hold is insufficient to rate the ingredient as effective for any condition—including constipation, anxiety, asthma, prostate cancer, common cold, or depression. The science hasn't settled whether it works for its intended purpose.
What are the side effects?
Concentrated orange extracts haven't been well studied for side effects. The only adverse effect on record is intestinal cramping reported in children who ate large amounts of orange peel. For a concentrated supplement, use caution and watch how you feel.
Why does this interact with so many medications?
The extract comes from sweet orange, and orange juice is well known to interfere with how your body absorbs and processes many drugs. It blocks key transporters in your gut (like OATP and P-glycoprotein) that let drugs pass through the intestinal wall. That's why it can weaken some drugs or strengthen others dangerously.
If I take this product with orange juice, does the effect get worse?
The data we hold doesn't directly address stacking this extract with fresh orange juice. But since they're the same source, it's logical that drinking juice alongside it could intensify the interaction. Check with your pharmacist about how much orange juice, if any, is safe while taking this product.
Can I just space out my medication and this supplement by a few hours?
For OATP substrates, you need at least 4 hours between the two. For other drugs—especially pravastatin, celiprolol, and ivermectin—spacing alone may not be enough. Your pharmacist can tell you whether spacing works for your specific medications or if you need to avoid the combination altogether.

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.

TrueSlim label
Go deeper

The Full Monographs Behind TrueSlim’s Ingredients

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

Herb & supplement monograph

Sweet Orange

Interacts with 246 drugs

Sweet orange is a common citrus fruit that is a good source of vitamin C, fiber, and antioxidants, and is enjoyed as a food worldwide. Its peel and essential oil are used in aromatherapy and...

Read the full Sweet Orange monograph →
Sources

Sources & How We Checked

TrueSlim'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 17 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.

Sweet Orange 17 references
  1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  2. FDA, CFSAN. FDA-approved potassium health claim notification for potassium containing foods. 2000. Available at: www.cfsan.fda.gov/~dms/hclm-k.html.
  3. Kurowska EM, Spence JD, Jordan J, et al. HDL-cholesterol-raising effect of orange juice in subjects with hypercholesterolemia. Am J Clin Nutr 2000;72:1095-100. PubMed
  4. Murry JJ, Healy MD. Drug-mineral interactions: a new responsibility for the hospital dietician. J Am Diet Assoc 1991;91:66-73.
  5. Bailey DG, Dresser GK, Munoz C, et al. Reduction of fexofenadine bioavailability by fruit juices. Clin Pharmacol Ther 2001;69:P21.
  6. Pletz MW, Petzold P, Allen A, et al. Effect of calcium carbonate on bioavailability of orally administered gemifloxacin. Antimicrob Agents Chemother 2003;47:2158-60.. PubMed
  7. Lilja JJ, Juntti-Patinen L, Neuvonen PJ. Orange juice substantially reduces the bioavailability of the beta-adrenergic-blocking agent celiprolol. Clin Pharmacol Ther 2004;75:184-90.
  8. Tian R, Koyabu N, Takanaga H, et al. Effects of grapefruit juice and orange juice on the intestinal efflux of P-glycoprotein substrates. Pharm Res 2002;19:802-9. PubMed
  9. Vanapalli SR, Chen Y, Ellingrod VL, et al. Orange juice decreases the oral bioavailability of ivermectin in health volunteers. Clin Pharmacol Ther 2003;73 (Abstract PDII-A-10):P94.
  10. Huang SM, Lesko LJ. Drug-drug, drug-dietary supplement, and drug-citrus fruit and other food interactions: what have we learned? J Clin Pharmacol 2004;44:559-69. PubMed
  11. Koitabashi Y, Kumai T, Matsumoto N, et al. Orange juice increased the bioavailability of pravastatin, 3-hydroxy-3-methylglutaryl CoA reductase inhibitor, in rats and healthy human subjects. Life Sci 2006;78:2852-9. PubMed
  12. Takanaga H, Ohnishi A, Yamada S, et al. Polymethoxylated flavones in orange juice are inhibitors of P-glycoprotein but not cytochrome P450 3A4. J Pharmacol Exp Ther 2000;293:230-6. DOI
  13. Greenblatt DJ. Analysis of drug interactions involving fruit beverages and organic anion-transporting polypeptides. J Clin Pharmacol 2009;49:1403-7. PubMed
  14. Bailey DG. Fruit juice inhibition of uptake transport: a new type of food-drug interaction. Br J Clin Pharmacol 2010;70:645-55. PubMed
  15. Kamath AV, Yao M, Zhang Y, Chong S. Effect of fruit juices on the oral bioavailability of fexofenadine in rats. J Pharm Sci 2005;94:233-9. PubMed
  16. Kays MB, Overholser BR, Mueller BA, et al. Effects of sevelamer hydrochloride and calcium acetate on the oral bioavailability of ciprofloxacin. Am J Kidney Dis. 2003;42(6):1253-9. PubMed
  17. Neuhofel, A. L., Wilton, J. H., Victory, J. M., Hejmanowsk, L. G., and Amsden, G. W. Lack of bioequivalence of ciprofloxacin when administered with calcium-fortified orange juice: a new twist on an old interaction. J Clin Pharmacol. 2002;42(4):461-466. DOI

See these in context on the Sweet Orange monograph →

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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