Drug & supplement interaction

Agar + Insulin (rDNA)

Insulin (rDNA) brand names: Humalog, Humalog Mix 75/25, Humulin R, Humulin N, Humulin L, and others.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Agar and Insulin (rDNA) in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the label for Insulin (rDNA) states a food rule worth keeping to.

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Interaction report

Agar and Insulin (rDNA)

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Insulin (rDNA) and Agar in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Agar safety at a glance

Agar overall Use caution Generally safe as a food, but supplement doses should be taken with plenty of water to avoid blockage.
Pregnancy Use caution Likely fine in normal food amounts, but avoid concentrated supplement doses unless your doctor approves.
Breastfeeding Use caution Food amounts are likely fine, but there is little safety data on supplement doses.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Insulin (rDNA) and Agar? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Insulin (rDNA)

Interactions in our licensed database are recorded against drug classes, not just single drug names. Insulin (rDNA) is filed under 2 classifications — including antidiabetes drugs. Agar has documented interactions with 1 drug class — the most serious being oral drugs (minor) — and none of Insulin (rDNA)’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Agar Does Interact With Other Medications

Agar has 2,022 minor known drug interactions in our database — Insulin (rDNA) isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Agar

Covers the 2,830 medications we’ve checked against Agar. Pick one to open its full report.

What to actually watch for

What Agar Itself Has Been Linked To

This is not an interaction — nothing below involves Insulin (rDNA). It is the side-effect record for Agar on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Agar, this list is the first place to look. One entry is worth acting on rather than waiting out — marked below.

  • A bowel blockage Worth acting on Additional detail

    “Orally, no adverse effects have been reported; however, a thorough evaluation of safety outcomes has not been conducted. Rarely, phytobezoars and esophageal or bowel obstruction have been reported after ingestion of high-fiber foods, such as agar (12,30500).”

    Agar · Natural Medicines adverse-effect record, reported in bowel obstruction.

    2 sources cited
    1. 12. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
    2. 30500. Osada, T., Shibuya, T., Kodani, T., Beppu, K., Sakamoto, N., Nagahara, A., Ohkusa, T., Ogihara, T., and Watanabe, S. Obstructing small bowel bezoars due to an agar diet: diagnosis using double balloon enteroscopy. Intern.Med 2008;47(7):617-620. PubMed

    “Orally, phytobezoars, which are concentrations of fruit and vegetable fibers in the gastrointestinal tract, have been rarely reported following ingestion of high-fiber foods, such as agar. Esophageal or bowel obstruction has also been reported when agar is consumed without sufficient fluid intake (12).”

    Agar · Natural Medicines adverse-effect record, reported in bowel obstruction.

    2 sources cited
    1. 30500. Osada, T., Shibuya, T., Kodani, T., Beppu, K., Sakamoto, N., Nagahara, A., Ohkusa, T., Ogihara, T., and Watanabe, S. Obstructing small bowel bezoars due to an agar diet: diagnosis using double balloon enteroscopy. Intern.Med 2008;47(7):617-620. PubMed
    2. 12. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.

Everything above comes from the Natural Medicines adverse-effect record for Agar — expand a row for the licensed statement it rests on. We read the ADVERSE REACTIONS section of Insulin (rDNA)’s FDA label too, and the two lists don’t meaningfully overlap — which is why no Insulin (rDNA) column appears here.

How to take them

Some Insulin (rDNA) Products Have a Food Rule — Agar Should Not Break It

At least one FDA label for a product containing Insulin (rDNA) says to take it with food. If you take Agar on an empty stomach out of habit, keep them separate — and take Insulin (rDNA) with a meal where the label says to.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Insulin (rDNA) products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.

( 2.1 , 2.2 , 2.3 , 2.4 ) Subcutaneous injection ( 2.2 ): Administer HUMALOG ® U-100 or U-200 by subcutaneous injection into the abdominal wall, thigh, upper arm, or buttocks within 15 minutes before a meal or immediately after a meal.

From the Dosage and Administration section of the FDA label we read for Insulin (rDNA) — where that label names a specific product, the instruction is that product's. See the Insulin (rDNA) drug page ›

A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.

Overlapping uses

What Insulin (rDNA) Is Prescribed For, and What Agar Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Insulin (rDNA) is a prescription medicine with approved uses on its FDA label. Agar is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Insulin (rDNA) is prescribed for: Insulin lispro injection is used to improve glycemic control (blood sugar management) in people with diabetes mellitus. It is a rapid-acting insulin analog approved for use in both type 1 and type 2 diabetes. Admelog is specifically indicated to improve glycemic control in patients with diabetes mellitus. Humalog Mix75/25 is indicated to improve glycemic control in adults with diabetes mellitus; it is a fixed-ratio mixture of insulin lispro and insulin lispro protamine, and its fixed proportions do not allow for separate adjustment of basal (background) and prandial (mealtime) doses.

Agar has been studied for:

  • Diabetes studied, not established Agar has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Agar for diabetes

    Preliminary clinical research in obese patients with type 2 diabetes and impaired glucose tolerance shows that consuming seasoned agar gel (Slim Kanten, Choshiya) 180 grams daily in combination with a conventional Japanese diet for 12 weeks does not improve fasting plasma glucose or insulin resistance when compared to the conventional Japanese diet alone.

    1 source cited
    1. 30496. Maeda, H., Yamamoto, R., Hirao, K., and Tochikubo, O. Effects of agar (kanten) diet on obese patients with impaired glucose tolerance and type 2 diabetes. Diabetes Obes.Metab 2005;7(1):40-46.

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Insulin (rDNA) on your own; if you are taking Agar for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

Everything else you take

See Every Supplement That Interacts With Insulin (rDNA)

This page covers Agar only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Insulin (rDNA) page lists 242 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Chelation Therapy Products (major), Siberian Cocklebur (major), Acai (moderate), African Wild Potato (moderate) and Agaricus Mushroom (moderate).

By severity: 2 major · 211 moderate · 29 minor.

From our pharmacist’s overview on the Insulin (rDNA) page

“A weed called Siberian cocklebur has caused severe low blood sugar in humans and is the one ingredient to avoid outright while using insulin (rDNA) products like Humalog or Humulin. This list deserves real respect.”

Reviewed by 2 · Jul 18, 2026

Open the Insulin (rDNA) interaction page

One more smart check

Taking Agar as Part of a Dietary Supplement Product? Check It for Interactions

We hold 23 real supplement products containing Agar, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Agar. Even though Agar itself has no known interaction with Insulin (rDNA), another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Agar and Insulin (rDNA) Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Agar
Top half

#517 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Insulin (rDNA)
Top half

#781 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Agar reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Agar and Insulin (rDNA) records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Agar

What is Agar?

Agar
  • Constipation
  • Weight loss
  • Vegetarian gelatin substitute
  • Source of dietary fiber
  • Appetite control

Agar is a plant-based gel made from red seaweed that is widely used as a vegetarian alternative to gelatin and as a source of dietary fiber. It is sometimes taken as a bulk-forming laxative or weight-loss aid, but solid human evidence for these health uses is limited. It is generally considered safe as a food, but you should drink plenty of water with it and check with your pharmacist before using it as a supplement.

Cell wall extract of red algae (seaweed) · Powder, flakes, bars, capsules, food-grade gel

An interaction check asks whether these two react with each other — it does not ask whether Agar is a good idea for someone in your situation. Here is what our Agar record says about it on its own.

Agar: dosing

There is no official, well-established medical dose of agar. The amount used in cooking depends on the recipe, and supplement products vary widely.If you use an agar supplement, follow the directions on the product label and take it with plenty of water.

From our Agar monograph — the full record covers uses, side effects and every documented interaction.

Read the full Agar monograph & all interactions
Medication

About Insulin Lispro Injection

What Is Insulin Lispro Injection Used For?

Brand names: Humalog, Humalog Mix 75/25, Humulin R, Humulin N, Humulin L, Humulin 50/50, Humulin 70/30, Humulin U, NovoLog, Velosulin, Novolog Mix 70/30, Actrapid, Humulin S, Insuman Rapid

Insulin lispro injection is used to improve glycemic control (blood sugar management) in people with diabetes mellitus. It is a rapid-acting insulin analog approved for use in both type 1 and type 2 diabetes.

Admelog is specifically indicated to improve glycemic control in patients with diabetes mellitus. Humalog Mix75/25 is indicated to improve glycemic control in adults with diabetes mellitus; it is a fixed-ratio mixture of insulin lispro and insulin lispro protamine, and its fixed proportions do not allow for separate adjustment of basal (background) and prandial (mealtime) doses.

See full Insulin Lispro Injection drug information
Keep checking

Other Drugs & Agar

Browse every other medication we’ve checked against Agar — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
0Moderate
2,022Minor
807No known interaction
Minor

2,022 interactions

Showing 60 of 2,022 minor interactions — see all 2,022 on the Agar page.

No interaction 807 drugs checked — show the list

We also checked Agar against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 807 medications checked with no known interaction — see the full Agar list.

Evidence & sources

Agar References

The 13 references that drive our Agar 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.

  1. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  3. Kondo H, Osada A. Influence of dietary fiber on the bioavailability of zinc in rats. Biomed Environ Sci. 1996 Sept;9(2-3):204-8.
  4. Romagnoli, C., Polidori, G., Foschini, M., Cataldi, L., De, Turris P., Tortorolo, G., and Mastrangelo, R. Agar in the management of hyperbilirubinaemia in the premature baby. Arch.Dis.Child 1975;50(3):202-204. PubMed
  5. Windorfer, A., Jr., Kunzer, W., Bolze, H., Ascher, K., Wilcken, F., and Hoehne, K. Studies on the effect of orally administered agar on the serum bilirubin level of premature infants and mature newborns. Acta Paediatr.Scand. 1975;64(5):699-702. PubMed
  6. Maeda, H., Yamamoto, R., Hirao, K., and Tochikubo, O. Effects of agar (kanten) diet on obese patients with impaired glucose tolerance and type 2 diabetes. Diabetes Obes.Metab 2005;7(1):40-46.
  7. Osada, T., Shibuya, T., Kodani, T., Beppu, K., Sakamoto, N., Nagahara, A., Ohkusa, T., Ogihara, T., and Watanabe, S. Obstructing small bowel bezoars due to an agar diet: diagnosis using double balloon enteroscopy. Intern.Med 2008;47(7):617-620. PubMed
  8. Kemper, K., Horwitz, R. I., and McCarthy, P. Decreased neonatal serum bilirubin with plain agar: a meta-analysis. Pediatrics 1988;82(4):631-638. DOI
  9. Meloni, T., Costa, S., Corti, R., and Cutillo, S. Agar in control of hyperbilirubinemia of full-term newborn infants with erythrocyte G-6-PD deficiency. Biol.Neonate 1978;34(5-6):295-298. PubMed
  10. Maurer, H. M., Shumway, C. N., Draper, D. A., and Hossaini, A. A. Controlled trial comparing agar, intermittent phototherapy, and continuous phototherapy for reducing neonatal hyperbilirubinemia. J Pediatr. 1973;82(1):73-76.
  11. Caglayan, S., Candemir, H., Aksit, S., Kansoy, S., Asik, S., and Yaprak, I. Superiority of oral agar and phototherapy combination in the treatment of neonatal hyperbilirubinemia. Pediatrics 1993;92(1):86-89. DOI
  12. Harmuth-Hoene, A. E. and Schelenz, R. Effect of dietary fiber on mineral absorption in growing rats. J Nutr 1980;110(9):1774-1784. PubMed
  13. Abdel-Aziz Ali SMA, Mansour Galal S, Sror SM, Hussein O, Abd-El-Haseeb Ahmed AO, Hamed EA. Efficacy of oral agar in management of indirect hyperbilirubinemia in full-term neonates. J Matern Fetal Neonatal Med. 2020:1-6. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Agar and Insulin (rDNA) Together: Common Questions

Is it safe to take Agar with Insulin (rDNA)?
We do not list a known interaction between Agar and Insulin (rDNA). That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Should I take Agar and Insulin (rDNA) at the same time of day?
At least one FDA label for a product containing Insulin (rDNA) says to take it with food. If you take Agar on an empty stomach out of habit, keep them separate and take Insulin (rDNA) with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Insulin (rDNA) products can differ — so check the directions on your own box. This is about absorption, not an interaction.
Are Agar and Insulin (rDNA) used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Agar in each. That is a conversation for your prescriber, especially if Insulin (rDNA) is being adjusted to a target.
How was the Agar and Insulin (rDNA) combination checked?
Interactions in our licensed database are recorded against drug classes. Insulin (rDNA) is filed under 2 classifications, and Agar has documented interactions with 1 drug class — none of Insulin (rDNA)'s classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Agar interact with any other medications?
Yes. Agar has 2,022 documented drug interactions in our database — Insulin (rDNA) is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Insulin (rDNA) interact with any supplements?
Yes. Insulin (rDNA) has documented interactions with 242 supplements in our database — Agar is not one of them. The Insulin (rDNA) interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Insulin (rDNA) and Agar?

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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.