Annatto Drug Interactions, Uses, Effectiveness, Safety & More
What is this page for?
First and foremost: how Annatto interacts with medications. The heart of this page is the interaction list — every drug Annatto is known to interact with, and how serious each one is.
But these pages have grown well beyond that into a full monograph — what Annatto is, what people use it for and how strong the evidence is, its safety and side effects, and answers to the questions we’re asked most — written and reviewed by the clinical staff at HelloPharmacist. It’s educational information from our licensed clinical databases, not medical advice, and we don’t sell or endorse products. Our editorial policy
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Add one medicationAnnatto Drug Interactions: The Bottom Line
From the HelloPharmacist Editorial Team · Updated July 2026Based on the available evidence, the overall risk of a clinically significant Annatto drug interaction appears low for most people, since the concerns identified so far rest on animal research rather than proven effects in humans. None of the listed interactions are rated major, and although a fair number of medications appear, they are all rated moderate and trace back to a single, poorly documented concern.
The one area worth watching is diabetes medications. Animal studies suggest annatto extracts might raise or lower blood sugar, so in theory it could blunt these drugs or add to their glucose-lowering effect. Because blood sugar control is closely monitored, people taking insulin or oral diabetes drugs should keep an eye on their readings and mention annatto to their prescriber. This has not been confirmed in human studies.
The long list of interacting medications can look worrying, but nearly all of it reflects that one theoretical blood sugar concern applied across the many drugs used to treat diabetes. A predicted effect in animals or the lab does not mean a harmful interaction actually happens in people, and for annatto no interaction has been well documented in humans so far.
Based on HelloPharmacist’s Annatto interaction data and reviewed under our editorial standards.
Drugs that interact with Annatto
86 medications have a known interaction with Annatto, graded by severity. Select any drug for the full evidence-based detail.
Don’t want to scroll the list? Just ask.
Tell us the medications you take and we’ll check each one against Annatto using our pharmacist-reviewed interaction data.
AI summaries are generated from our Annatto interaction data for education only — always confirm with your pharmacist. How we use AI
No drugs match “”.
What Severity, Likelihood & Evidence Mean
Severity — How Serious It Can Be
- Major. Clinically significant; generally best avoided, or used only under direct professional supervision.
- Moderate. May need monitoring, a dose adjustment, or separating the times you take each one.
- Minor. Generally not clinically significant, but still worth noting and mentioning to your pharmacist.
- No known interaction. Checked against our sources with nothing documented — not the same as proven safety.
Likelihood — How Well It’s Documented
- Likely. Well-controlled human studies have demonstrated the likely existence of this interaction
- Probable. Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
- Possible. Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
- Unlikely. Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Where This Data Comes From
- Interaction records are evidence-graded and sourced from the Natural Medicines database (TRC Healthcare), the same reference used by pharmacists and hospitals.
- Each drug listed above links to the full report for that exact Annatto combination — clinical detail, likelihood, evidence level, and citations.
- Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.
The kinds of drugs Annatto affects
Every type of medication (drug category) Annatto is known to interact with. Open any category for the detail — or search your exact drug in the checker above.
Antidiabetes Drugs
Animal studies suggest that certain annatto extracts may have hypoglycemic or hyperglycemic effects. Theoretically, taking annatto with antidiabetes drugs could reduce the therapeutic effects of these drugs or increase the risk for additive hypoglycemia. Monitor blood glucose levels closely.
Annatto: Uses, Safety & Side Effects
Annatto is a plant-based coloring made from the seeds of the achiote tree and is widely used as a safe food dye. While it has a long history in traditional medicine and contains antioxidant compounds, there is little high-quality human research supporting its use as a supplement. It can trigger allergic reactions in some people, so use caution and talk with your pharmacist or doctor.

- Scientific name
- Bixa orellana
- Family
- Bixaceae
- Part used
- Seeds (and the colored coating around them); leaves are sometimes used
- Common forms
- Food coloring, powder, seed extract, capsules, oil-based extracts
- Natural food and cosmetic coloring
- Source of antioxidants
- Antimicrobial/anti-infective (traditional use)
- Athletic performance and muscle soreness
- Skin and bad-breath remedies (traditional use)
Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.
Generally recognized as safe as a food coloring, but supplement use is not well studied and it can cause allergies in some people.
There is insufficient reliable information available about the safety of annatto during pregnancy and breast-feeding.
Read the full pregnancy detailThere is insufficient reliable information available about the safety of annatto during pregnancy and breast-feeding.
Read the full breastfeeding detailPregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center). Safety guidance is general; always confirm with your pharmacist or doctor for your situation.
Overview
Annatto is a natural coloring made from the seeds of the achiote tree (Bixa orellana). This small tree grows in tropical parts of Central and South America and is now found in many warm regions around the world. The tree produces spiky red pods filled with small seeds covered in a red-orange coating.
The seeds are ground into a powder or made into a paste or oil to add a yellow, orange, or red color to foods like cheese, butter, rice, and snack foods. People also use annatto to dye fabric and cosmetics. In addition to coloring, the seeds have a mild, slightly sweet and peppery flavor and are used as a spice in some cuisines.
Beyond cooking, annatto has been used in traditional medicine for many purposes, such as a source of antioxidants and as a folk remedy for skin and infections.
How it works
The orange-red color of annatto comes mainly from a pigment called bixin and a related compound called norbixin. These are types of carotenoids, the same family of plant pigments found in carrots and tomatoes.
In laboratory studies, these carotenoids act as antioxidants, meaning they may help neutralize unstable molecules called free radicals. Annatto also contains tocotrienols, which are a form of vitamin E. Some lab and animal research suggests possible antimicrobial and anti-inflammatory effects.
It is important to remember that most of this information comes from test-tube and animal research. What happens in a lab does not always carry over to real benefits in people.
Does Annatto work?
How to read these evidence grades
Natural Medicines’ 7-point scale. We show each rating’s label word-for-word.
For Annatto, current evidence isn’t strong enough to rate any specific use. The conditions it has been studied for are listed below.
Also studied for 4 conditions — evidence insufficient to rate
Insufficient Reliable Evidence To Rate Athletic performance
Preliminary clinical research in adult male athletes shows that taking a specific supplement containing annatto powder 143 mg and ginger powder 190 mg (ReWin(d), Natural Origins), 6 capsules daily, increases muscle power during repeat eccentric exercise when compared with placebo. The supplement was taken for 4 weeks prior to, and 3 days after, the eccentric exercise. Another small clinical trial in male recreational runners aged 40-60 years with chronic knee discomfort shows that taking a product containing annatto seed, devil's claw root, and ginger rhizome in a ratio of 0.375:1:0.75 (Exten(d), Natural Origins), 2 grams orally daily in 3 divided doses for 4 weeks, reduces leg fat mass when compared with placebo. It is unclear if knee discomfort is improved, or whether the effects are due to annatto, other ingredients, or the combination.
Insufficient Reliable Evidence To Rate Benign prostatic hyperplasia (BPH)
Preliminary clinical research in adults with BPH and moderate lower urinary tract symptoms shows that taking powdered annatto leaf 250 mg three times daily for 12 months does not improve symptoms when compared with placebo.
Insufficient Reliable Evidence To Rate Exercise-induced muscle soreness
Preliminary clinical research in adult male athletes shows that taking a specific supplement containing annatto powder 143 mg and ginger powder 190 mg (ReWin(d), Natural Origins), 6 capsules daily, reduces muscle soreness after eccentric exercise when compared with placebo. However, blood creatine kinase levels were not different between groups. The supplement was taken for 4 weeks prior to, and 3 days after, the eccentric exercise.
Insufficient Reliable Evidence To Rate Halitosis
Preliminary clinical research in adults with halitosis shows that applying annatto extract 20% to the tongue as a photosensitizer for antimicrobial photodynamic therapy (aPDT) immediately reduces volatile sulfur levels in the mouth when compared with baseline. However, after 7 days, volatile sulfur levels were similar to baseline levels. The changes in volatile sulfur levels were similar to those treated with tongue scraping or tongue scraping followed by aPDT. However, the study may have been inadequately powered to detect a difference between groups.
Source & disclaimer. Effectiveness ratings and evidence summaries are provided by Natural Medicines (Therapeutic Research Center) and shown as licensed. Where Natural Medicines hasn’t rated a use, HelloPharmacist’s pharmacists may add their own reviewed rating and evidence (each such entry is labeled). This is educational information, not medical advice — talk with your pharmacist or doctor before starting, stopping, or changing a supplement.
Safety & precautions
As a food coloring, annatto is widely used and generally considered safe in the small amounts found in foods. Less is known about the safety of concentrated supplement doses, which have not been well studied.
The main concern is allergic reactions. Some people have reported reactions to annatto in foods, ranging from mild to more serious. If you have known food or color allergies, be cautious.
For pregnancy and breastfeeding, the amounts used to color food are likely fine, but there is not enough information on the safety of supplement-strength annatto. To be safe, avoid concentrated supplements during pregnancy and breastfeeding unless your doctor approves. Children, older adults, and people with chronic illness should also check with a healthcare provider before using annatto supplements.
Side effects
When used as a food coloring, annatto rarely causes problems for most people. The most reported side effect is an allergic reaction. Symptoms can include hives, itching, swelling, stomach upset, or in rare cases more severe reactions such as trouble breathing.
If you notice signs of a serious allergic reaction, such as swelling of the lips, tongue, or throat, or difficulty breathing, stop using it and seek emergency medical care right away.
Because supplement doses are not well studied, other side effects are possible but not well documented.
Annatto: Reported Adverse Effects
Documented safety reports on Annatto from the evidence-graded Natural Medicines (TRC Healthcare) database, shown word-for-word from the licensed record.
Orally, annatto leaf seems to be well tolerated. Rarely, annatto has been reported to cause constipation. When used as a coloring agent, annatto has been reported to cause allergic reactions, including anaphylaxis.
- Zegarra, L., Vaisberg, A., Loza, C., Aguirre, R. L., Campos, M., Fernandez, I., Talla, O., and Villegas, L. Double-blind randomized placebo-controlled study of Bixa orellana in patients with lower urinary tract symptoms associated to benign prostatic hyp
- Ebo, D. G., Ingelbrecht, S., Bridts, C. H., and Stevens, W. J. Allergy for cheese: evidence for an IgE-mediated reaction from the natural dye annatto. Allergy 2009;64(10):1558-1560.
- Nish, W. A., Whisman, B. A., Goetz, D. W., and Ramirez, D. A. Anaphylaxis to annatto dye: a case report. Ann.Allergy 1991;66(2):129-131.
- Koc E, Arca E, Surucu B, Kurumlu Z. An open, randomized, controlled, comparative study of the combined effect of intralesional triamcinolone acetonide and onion extract gel and intralesional triamcinolone acetonide alone in the treatment of hypertrophic s
- Raddatz-Mota D, Pérez-Flores LJ, Carrari F, et al. Achiote (Bixa orellana L.): a natural source of pigment and vitamin E. J Food Sci Technol 2017;54(6):1729-1741.
Constipation Gastrointestinal
Orally, annatto leaf powder has been reported to cause constipation. Annatto food coloring has been associated with an increase in symptoms of irritable bowel syndrome (IBS) in one case report. A woman with frequent symptoms of diarrhea, bloating, and abdominal pain experienced an improvement in all symptoms upon elimination of annatto-containing products; symptoms returned after these products were added back into her diet.
- Zegarra, L., Vaisberg, A., Loza, C., Aguirre, R. L., Campos, M., Fernandez, I., Talla, O., and Villegas, L. Double-blind randomized placebo-controlled study of Bixa orellana in patients with lower urinary tract symptoms associated to benign prostatic hyp
- Stein HL. Annatto and IBS. J Clin Gastroenterol 2009;43(10):1014-5.
Hypotension Immunologic
When used as a food coloring, annatto causes rare cases of allergic reactions in children and adults. Reactions have occurred after consumption of cereal, cheese, ice cream, and other foods containing annatto food coloring, and use of cosmetics containing annatto. Symptoms include urticaria, angioedema, severe hypotension, and anaphylaxis (31619,31621,95157.109549). One patient with a history of urticaria after using cosmetics, or ingesting food containing annatto, was given oral doses of annatto gradually increasing from 1 mg to 100 mg at hourly intervals. Severe urticaria requiring treatment with antihistamines and corticosteroids occurred with doses of 50-100 mg, while milder reactions started at around 20 mg. Reactions to annatto food coloring are possibly due to traces of seed protein.
- Sadowska B, Sztormowska M, Chelminska M. Annatto hypersensitivity after oral ingestion confirmed by placebo-controlled oral challenge. Ann Allergy Asthma Immunol. 2021 Oct;127(4):510-511.
- Raddatz-Mota D, Pérez-Flores LJ, Carrari F, et al. Achiote (Bixa orellana L.): a natural source of pigment and vitamin E. J Food Sci Technol 2017;54(6):1729-1741.
Adverse-effects data: Natural Medicines, Therapeutic Research Center
Dosing
There is no established standard dose for annatto as a supplement. The amounts used to color foods are very small, and research has not defined a safe or effective dose for health purposes.
If you use an annatto supplement, follow the directions on the product label and do not exceed the recommended amount. Because supplement quality and strength can vary widely, it is a good idea to choose products from reputable brands and to check with your pharmacist or doctor before starting.
Annatto & Pregnancy
Annatto & Breastfeeding
© 2026 Therapeutic Research Center
Pregnancy & lactation ratings: Natural Medicines, Therapeutic Research Center
References & further reading
The 15 references that drive our Annatto monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.
- Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
- Fernandes, A. C., Almeida, C. A., Albano, F., Laranja, G. A., Felzenszwalb, I., Lage, C. L., de Sa, C. C., Moura, A. S., and Kovary, K. Norbixin ingestion did not induce any detectable DNA breakage in liver and kidney but caused a considerable impairment
- Russell, K. R., Morrison, E. Y., and Ragoobirsingh, D. The effect of annatto on insulin binding properties in the dog. Phytother Res 2005;19(5):433-436. PubMed
- Morrison, E. Y., Thompson, H., Pascoe, K., West, M., and Fletcher, C. Extraction of an hyperglycaemic principle from the annatto (Bixa orellana), a medicinal plant in the West Indies. Trop.Geogr.Med 1991;43(1-2):184-188.
- Zegarra, L., Vaisberg, A., Loza, C., Aguirre, R. L., Campos, M., Fernandez, I., Talla, O., and Villegas, L. Double-blind randomized placebo-controlled study of Bixa orellana in patients with lower urinary tract symptoms associated to benign prostatic hyp
- Russell, K. R., Omoruyi, F. O., Pascoe, K. O., and Morrison, E. Y. Hypoglycaemic activity of Bixa orellana extract in the dog. Methods Find.Exp.Clin.Pharmacol. 2008;30(4):301-305.
- Ebo, D. G., Ingelbrecht, S., Bridts, C. H., and Stevens, W. J. Allergy for cheese: evidence for an IgE-mediated reaction from the natural dye annatto. Allergy 2009;64(10):1558-1560. PubMed
- Nish, W. A., Whisman, B. A., Goetz, D. W., and Ramirez, D. A. Anaphylaxis to annatto dye: a case report. Ann.Allergy 1991;66(2):129-131.
- Stein HL. Annatto and IBS. J Clin Gastroenterol 2009;43(10):1014-5.
- Raddatz-Mota D, Pérez-Flores LJ, Carrari F, et al. Achiote (Bixa orellana L.): a natural source of pigment and vitamin E. J Food Sci Technol 2017;54(6):1729-1741. PubMed
- Koc E, Arca E, Surucu B, Kurumlu Z. An open, randomized, controlled, comparative study of the combined effect of intralesional triamcinolone acetonide and onion extract gel and intralesional triamcinolone acetonide alone in the treatment of hypertrophic s
- Gonçalves MLL, da Mota ACC, Deana AM, et al. Antimicrobial photodynamic therapy with Bixa orellana extract and blue LED in the reduction of halitosis-A randomized, controlled clinical trial. Photodiagnosis Photodyn Ther. 2020 Jun;30:101751. PubMed
- Dominguez-Balmaseda D, Diez-Vega I, Larrosa M, et al. Effect of a blend of Zingiber officinale Roscoe and Bixa orellana L. herbal supplement on the recovery of delayed-onset muscle soreness induced by unaccustomed eccentric resistance training: A randomiz
- González-Gross M, Quesada-González C, Rueda J, et al. Analysis of effectiveness of a supplement combining Harpagophytum procumbens, Zingiber officinale and Bixa orellana in healthy recreational runners with self-reported knee pain: a pilot, randomized, tr
- Sadowska B, Sztormowska M, Chelminska M. Annatto hypersensitivity after oral ingestion confirmed by placebo-controlled oral challenge. Ann Allergy Asthma Immunol. 2021 Oct;127(4):510-511. PubMed
This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.
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
Brands that make products with Annatto
380 brands in our database make a supplement containing Annatto.
Supplement products with Annatto
1,881 products in our database contain Annatto. Open any to see its full ingredient list and every drug interaction we check.
Annatto: Common Questions
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Does Annatto interact with prescription medications?
How are Annatto interactions rated?
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Where does this Annatto interaction information come from?
What is Annatto used for?
Is Annatto safe to eat?
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Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Products that contain Annatto
A rotating sample of real supplements in our database that list Annatto — open any to see its full ingredients and every drug interaction we check.
- Collagen Gummies 500 mg by Applied Nutrition
- Men's Once Daily by Garden of Life MyKind Organics
- Q-Gel Forte Coenzyme Q10 30 mg by Tishcon Corp.
- Liver Detox & Blood Refresh by Irwin Naturals
- CoQ10 Plus by Herbalife Nutrition
- Annatto by Hawaii Pharm
- Hair Support by NaturesPlus AgeLoss
- Disney Pirates Of The Caribbean Sour Gummies Multivitamin by NatureSmart
- Wheybolic Ripped Chocolate Fudge by GNC AMP Advanced Muscle Performance
- Probiotic with Prebiotic Fiber by L'il Critters
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