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Dietary supplement

Formula 681 Ingredients & Drug Interactions

by DC

Formula 681 label
See full label image
Capsule Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Formula 681 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: Moderate

Formula 681 is a dietary supplement by DC with 1 active ingredient. Its ingredients are commonly taken for general nutrition and energy, antioxidant support, cholesterol and metabolic health.Based on those ingredients, 628 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Spirulina. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Formula 681 by DC

Ask about any prescription or over-the-counter medication and we check it for interactions with Formula 681 by DC — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Formula 681 by DC

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 30, 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 2 of its 2 active ingredients.
  • “Spirulina” is listed as a grouped ingredient — the label gives one combined amount (500 mg) without saying how much of each component you get.

Formula 681 contains 2 active ingredients: natural chlorophyll and spirulina. Chlorophyll is the pigment that gives plants their green color and has been studied for various health purposes.

Spirulina is a blue-green algae used as a nutritional supplement. The capsules also contain gelatin and vegetable magnesium stearate as inactive ingredients.

Does it work?

Couldn't assess
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 assessable

This is a single-ingredient Chlorophyll product and its label doesn't state a use — see Chlorophyll's own graded uses on its monograph.

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.

The evidence we hold doesn't establish that natural chlorophyll is effective for genital herpes, wound healing, herpes zoster (shingles), nonmelanoma skin cancer, or pancreatitis—the data on these uses is insufficient. For spirulina, effectiveness information isn't in our data.

We don't have effectiveness ratings for high-quality protein as an ingredient.

The evidence, ingredient by ingredient Blue-green Algae Chlorophyll

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.

Chlorophyll is generally well tolerated in short-term use, though high-quality safety data are limited. The most common side effect is photosensitization—sensitivity to sunlight.

Topically, it can cause dermatitis. Rarely, oral use has been linked to pseudoporphyria (a blistering condition similar to porphyria).

Because there isn't enough reliable safety information, chlorophyll should be avoided during pregnancy. Safety during breastfeeding is unknown, so avoid it unless your doctor advises otherwise.

We don't have safety data on file for the other ingredients in this product.

Side effects, ingredient by ingredient Blue-green Algae Chlorophyll

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Chlorophyll.
  • The most serious interaction on file is rated Moderate.
  • For scale: 337 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, check with your own doctor or pharmacist if you take methotrexate (a drug used for cancer, autoimmune conditions, and other diseases)—chlorophyll may slow how your body clears it. Also double-check if you're on any photosensitizing medications (drugs that make your skin react to sunlight), since chlorophyll can intensify that effect.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This product is mainly a concern if you take methotrexate or medications that increase sun sensitivity—in those cases, you'll want to check with your doctor or pharmacist first. If you're pregnant or breastfeeding, the safety data on chlorophyll isn't strong enough to recommend it without talking it over with your own healthcare provider.

Short-term use appears generally well tolerated in people who aren't on interacting medications.

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

Assessment coverage: 1 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Apr 22, 2021.

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 Formula 681, straight from the product label.

Brand DC
Net contents 90 Capsule(s)
Market status On market
Date entered into DSLD Apr 22, 2021
DSLD ID 245143
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years), Kosher, Women (not pregnant or lactating), 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 Formula 681 by DC, 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)
IngredientAmount% DV
natural Chlorophyll30 mg--
Spirulina500 mg--
high quality Protein300 mg--

Other ingredients: Gelatin, Vegetable Magnesium Stearate

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

Directions: As a dietary supplement, take 1 capsule three times daily.

Formula

Spirulina is an aquatic plant made directly by the interaction of sunlight and water (photosynthesis). It is farmed in a controlled environment which is free of pesticides and pollutants. It is the most concentrated form of any known organic food and contains 18 of the 22 known amino acids, including all of the essential amino acids, making it a complete protein.

Spirulina 500 mg Blue green microalgae

Ko Kosher Service

Precautions

Tamper Evident: Do not use this product if imprinted foil seal under cap is broken or missing.

Keep out of reach of children.

Caution: If you are pregnant or nursing do not take this product.

Formulation

Mfg. in an FDA Registered Facility using Good Manufacturing Practices (GMPs)

Conforms to USP <2091> for weight. Meets USP <2040> disintegration for maximum bioavailability.

Gluten free

A protein-rich vegetable food source, high in essential nutrients.

Made in USA

Storage

Keep tightly closed. Store at room temperature: 59 degrees - 86 degrees F (15 degrees to 30 degrees C).

Seals/Symbols

Quali Pure

Ko Kosher Service

FDA Statement of Identity

Dietary Supplement

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

See for yourself

Formula 681 by DC label

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

Formula 681 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 Formula 681 by DC

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

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

Spirulina

Interacts with
327 drugs
500 mg per serving

Blue-green algae are nutrient-rich aquatic microorganisms (such as spirulina and Klamath Lake algae) taken as a supplement for energy, nutrition, and...

Spirulina monograph & interactions

Other (inactive) ingredients: Gelatin, Vegetable Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Formula 681 by DC Drug Interactions

Want to check YOUR meds against Formula 681?

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
628Drugs
628 Moderate

Ingredients driving the most interactions

Spirulina 327

Individual Drug Interactions

The ingredients in Formula 681 interact with 628 drugs. Click any drug to see the details.

1 of the 1 ingredient in Formula 681 interact with drugs. Each result below shows which ingredient is responsible. Spirulina

Each ingredient & the kinds of drugs it affects

For each ingredient in Formula 681 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.

Spirulina3 drug types · 327 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, spirulina blue-green algae might increase the risk of bleeding if used with other anticoagulant or antiplatelet drugs. However, this is unlikely.
Spirulina blue-green algae have shown antiplatelet and anticoagulant effects in vitro. However, one preliminary study in 24 patients receiving spirulina blue-green algae 2.3 grams daily for 2 weeks showed no effect on platelet activation or measures of clotting time.

Likelihood Unlikely Evidence D
Antidiabetes Drugs

Theoretically, taking blue-green algae with antidiabetes drugs might increase the risk of hypoglycemia.
Human research shows that spirulina blue-green algae can have hypoglycemic effects in patients with diabetes, at least some of whom were using antidiabetes drugs. However, blue-green algae does not seem to improve glycated hemoglobin (HbA1c) levels in patients with diabetes. A meta-analysis of animal studies also suggests that spirulina blue-green algae have hypoglycemic effects.

Likelihood Possible Evidence B
Immunosuppressants

Theoretically, concurrent use of blue-green algae might interfere with immunosuppressive therapy.
Blue-green algae have been shown to stimulate the immune system.

Likelihood Possible Evidence D
Spirulina full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Formula 681, from the product label.

DC

See all DC products
Name
Dee Cee Laboratories, Inc.
Street Address
304 Dee Cee Rd.
City
White House
State
TN
ZipCode
37188
Pharmacist Counseling Corner

Formula 681 by DC: Common Questions

Does Formula 681 by DC interact with any medications?
Yes. Based on its ingredients, Formula 681 has a known interaction with 628 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Formula 681 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.
What exactly is chlorophyll, and why is it in this product?
Chlorophyll is the green pigment plants use to capture sunlight. It's been studied for uses like wound healing and immune support, though the evidence we hold is insufficient to confirm it works for those purposes. It's included here as a nutritional ingredient.
Can I take this if I'm sensitive to the sun?
Chlorophyll can cause photosensitization—increased sensitivity to sunlight—especially with oral use. If you already have sun sensitivity or take medications that make you sun-sensitive, this product isn't the best choice. Talk to your doctor or pharmacist first.
Is it safe to take while pregnant?
No—there isn't enough reliable safety information about chlorophyll in pregnancy, so the data advises against it. If you're pregnant or planning to be, discuss this product with your doctor or pharmacist.
What about while breastfeeding?
Safety during breastfeeding is unknown. Unless your doctor advises otherwise, it's best to avoid it. Talk with your doctor or pharmacist if you're breastfeeding and considering this product.
What side effects might I notice?
The most common effect is photosensitization—your skin becomes more reactive to sun exposure. Rarely, oral chlorophyll has been linked to pseudoporphyria, a blistering condition on the hands. Significant adverse effects haven't been widely reported, but thorough safety testing hasn't been completed.
Does this product have fillers or additives?
Yes—the capsules contain gelatin and vegetable magnesium stearate as inactive ingredients. If you need a vegan option or have sensitivities to gelatin, you'll want to look elsewhere.

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.

Formula 681 label
Go deeper

The Full Monographs Behind Formula 681’s Ingredients

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

Herb & supplement monograph

Blue-green Algae

Interacts with 327 drugs

Blue-green algae are nutrient-rich aquatic microorganisms (such as spirulina and Klamath Lake algae) taken as a supplement for energy, nutrition, and general wellness. Evidence for most heal...

Read the full Blue-green Algae monograph → Herb & supplement monograph

Chlorophyll

Interacts with 337 drugs

Chlorophyll is the green pigment found in plants and algae, and supplements often use a stable form called chlorophyllin. It is most studied for reducing body and fecal odor and as a topical...

Read the full Chlorophyll monograph →
Sources

Sources & How We Checked

Formula 681'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 27 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.

Chlorophyll 5 references
  1. Mathews-Roth MM. Carotenoids in erythropoietic protoporphyria and other photosensitivity diseases. Ann N Y Acad Sci, 1993; 691:127-38. PubMed
  2. Belen'kii, G. B. and Krikun, B. L. [Treatment of herpes simplex and herpes zoster by chlorophyll preparations]. Sov.Med. 1971;34(1):151-152.
  3. Brooks SL, Sanders J, Seymour JF, Mellor JD. A case of delayed methotrexate clearance following administration of a complementary medication containing chlorophyll. J Oncol Pharm Pract. 2014 Jun;20(3):225-8. PubMed
  4. Rossi E, Borchard K, Cole JM. Pseudoporphyria following self-medication with chlorophyll. Australas J Dermatol. 2015 Feb;56(1):47-8. PubMed
  5. Zhao CY, Frew JW, Muhaidat J, et al. Chlorophyll-induced pseudoporphyria with ongoing photosensitivity after cessation - a case series of four patients. J Eur Acad Dermatol Venereol 2016;30(7):1239-42. PubMed

See these in context on the Chlorophyll monograph →

Blue-green Algae 22 references
  1. Jensen GS, Ginsberg DJ, Huerta P, et al. Consumption of Aphanizomenon flos-aquae has rapid effects on the circulation and function of immune cells in humans. A novel approach to nutritional mobilization of the immune system. JANA 2000;2:50-6.
  2. Iwasa M, Yamamoto M, Tanaka Y, et al. Spirulina-associated hepatotoxicity. Am J Gastroenterol 2002;97:3212-13. PubMed
  3. Hayashi O, Katoh T, Okuwaki Y. Enhancement of antibody production in mice by dietary Spirulina platensis. J Nutr Sci Vitaminol (Tokyo) 1994;40:431-41.. PubMed
  4. Vitale S, Miller NR, Mejico LJ, et al. A randomized, placebo-controlled, crossover clinical trial of super blue-green algae in patients with essential blepharospasm or Meige syndrome. Am J Ophthalmol 2004;138:18-32. PubMed
  5. Mani UV, Desai S, Iyer U. Studies on the long-term effect of spirulina supplementation on serum lipid profile and glycated proteins in NIDDM patients. J Nutraceut 2000;2(3):25-32. DOI
  6. Chiu HF, Yang SP, Kuo YL, et al. Mechanisms involved in the antiplatelet effect of C-phycocyanin. Br J Nutr 2006;95:435-40. PubMed
  7. Hsiao G, Chou PH, Shen MY, et al. C-phycocyanin, a very potent and novel platelet aggregation inhibitor from Spirulina platensis. J Agric Food Chem 2005;53:7734-40.
  8. Katz M, Levine AA, Kol-Degani H, Kav-Venaki L. A compound herbal preparation (CHP) in the treatment of children with ADHD: a randomized controlled trial. J Atten Disord 2010;14:281-91. PubMed
  9. Madhyastha, H. K., Radha, K. S., Sugiki, M., Omura, S., and Maruyama, M. Purification of c-phycocyanin from Spirulina fusiformis and its effect on the induction of urokinase-type plasminogen activator from calf pulmonary endothelial cells. Phytomedicine PubMed
  10. Mazokopakis, E. E., Karefilakis, C. M., Tsartsalis, A. N., Milkas, A. N., and Ganotakis, E. S. Acute rhabdomyolysis caused by Spirulina (Arthrospira platensis). Phytomedicine. 2008;15(6-7):525-527. PubMed
  11. Halidou, Doudou M., Degbey, H., Daouda, H., Leveque, A., Donnen, P., Hennart, P., and Dramaix-Wilmet, M. [The effect of spiruline during nutritional rehabilitation: systematic review]. Rev.Epidemiol.Sante Publique 2008;56(6):425-431.
  12. Konno, T., Umeda, Y., Umeda, M., Kawachi, I., Oyake, M., and Fujita, N. [A case of inflammatory myopathy with widely skin rash following use of supplements containing Spirulina]. Rinsho Shinkeigaku 2011;51(5):330-333. PubMed
  13. Le TM, Knulst AC, Röckmann H. Anaphylaxis to Spirulina confirmed by skin prick test with ingredients of Spirulina tablets. Food Chem Toxicol 2014;74:309-10. PubMed
  14. Rzymski P, Niedzielski P, Kaczmarek N, Jurczak T, Klimaszyk P. The multidisciplinary approach to safety and toxicity assessment of microalgae-based food supplements following clinical cases of poisoning. Harmful Algae 2015;46:34-42. DOI
  15. Petrus M, Culerrier R, Campistron M, et al. First case report of anaphylaxis to spirulin: identification of phycocyanin as responsible allergen. Allergy 2010;65(7):924-5. PubMed
  16. Marles RJ, Barrett ML, Barnes J, et al. United States Pharmacopeia safety evaluation of spirulina. Crit Rev Food Sci Nutr 2011;51(7):593-604. PubMed
  17. Majdoub H, Ben Mansour M, Chaubet F, et al. Anticoagulant activity of a sulfated polysaccharide from the green alga Arthrospira platensis. Biochim Biophys Acta 2009;1790(10):1377-81. PubMed
  18. Cha BG, Kwak HW, Park AR, et al. Structural characteristics and biological performance of silk fibroin nanofiber containing microalgae spirulina extract. Biopolymers 2014;101(4):307-18. PubMed
  19. Jensen GS, Drapeau C, Lenninger M, Benson KF. Clinical safety of a high dose of phycocyanin-enriched aqueous extract from Arthrospira (Spirulina) platensis: results from a randomized, double-Blind, placebo-controlled study with a focus on anticoagulant ac
  20. Hamedifard Z, Milajerdi A, Reiner Z, Taghizadeh M, Kolahdooz F, Asemi Z. The effects of spirulina on glycemic control and serum lipoproteins in patients with metabolic syndrome and related disorders: A systematic review and meta-analysis of randomized con
  21. Moradi S, Zobeiri M, Feizi A, Clark CCT, Entezari MH. The effects of spirulina (Arthrospira platensis) supplementation on anthropometric indices, blood pressure, sleep quality, mental health, fatigue status and quality of life in patients with ulcerative
  22. Ghanbari F, Amerizadeh A, Behshood P, Moradi S, Asgary S. Effect of microalgae arthrospira on biomarkers of glycemic control and glucose metabolism: a systematic Review and meta-analysis. Curr Probl Cardiol 2022;47(10):100942. PubMed

See these in context on the Blue-green Algae 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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