Drug & supplement interaction

Holly + Insulin (rDNA)

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

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 20, 2026
The bottom line No known interaction

We found no known interaction between Holly 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

Holly 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 Holly 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.

Worth understanding: our licensed dataset holds no drug-interaction record for Holly at all — not against Insulin (rDNA), and not against any other medication we track. This verdict therefore rests on the absence of any recorded data, not on research that looked at this combination and found nothing. We cannot rule an interaction out.

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.

Holly safety at a glance

Holly overall Use caution The berries are toxic if eaten, and there is little safety data on leaf preparations.
Pregnancy Unsafe When berries are ingested. There is insufficient reliable information available about the safety of holly leaves; avoid using. Read the full pregnancy detail
Breastfeeding Unsafe When berries are ingested. There is insufficient reliable information available about the safety of holly leaves; avoid using. Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Insulin (rDNA) and Holly? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

What Holly Itself Has Been Linked To

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

  • Diarrhea / Vomiting / Nausea Additional detail

    “Orally, ingestion of holly leaf can cause GI irritation, diarrhea, nausea, and vomiting (6,18). Holly leaf spines may tear or puncture skin or mucous membranes (6). Ingestion of as few as 2 holly berries can cause vomiting and diarrhea in small children (6). Ingestion of more than 5 holly berries can cause nausea, vomiting, and diarrhea (6,18). Ingestion of 20-30 holly berries can cause death (18).”

    Holly · Natural Medicines adverse-effect record, reported in diarrhea.

    2 sources cited
    1. 6. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
    2. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.

    “Orally, ingestion of holly leaf can cause GI irritation, diarrhea, nausea, and vomiting (6,18). Holly leaf spines may tear or puncture skin or mucous membranes (6). Ingestion of as few as 2 holly berries can cause vomiting and diarrhea in small children (6). Ingestion of more than 5 holly berries can cause nausea, vomiting, and diarrhea (6,18).”

    Holly · Natural Medicines adverse-effect record, reported in diarrhea.

    2 sources cited
    1. 6. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
    2. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.

Everything above comes from the Natural Medicines adverse-effect record for Holly — 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.

Special populations

Holly in Pregnancy & Breastfeeding

Pregnancy And Lactation Unsafe

When berries are ingested. There is insufficient reliable information available about the safety of holly leaves; avoid using.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

How to take them

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

At least one FDA label for a product containing Insulin (rDNA) says to take it with food. If you take Holly 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.

Everything else you take

See Every Supplement That Interacts With Insulin (rDNA)

This page covers Holly 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 Holly as Part of a Dietary Supplement Product? Check It for Interactions

We hold 11 real supplement products containing Holly, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Holly. Even though Holly 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 Holly 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 Holly
Steady interest

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

29 days ago today
Medication Insulin (rDNA)
Top half

#883 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 Holly reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Holly 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 Holly

What is Holly?

  • Fever
  • Cough and chest congestion
  • Joint pain (traditional use)
  • Digestive complaints
  • Mild diuretic

Holly (Ilex aquifolium) is a common ornamental shrub whose bright red berries are poisonous and should never be eaten. There is very little reliable human evidence supporting any health benefit of holly leaves, and because of safety concerns it is generally best avoided as a supplement unless guided by a knowledgeable healthcare professional.

Ilex aquifolium · Aquifoliaceae · Leaves and berries (and bark in some traditions) · Dried leaf tea, tinctures, and homeopathic preparations; berries are not used as a supplement

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

Holly: dosing

There is no established or standardized dose for holly, because it has not been properly studied as a medicine. We cannot provide a safe recommended amount.If you choose to use a commercial holly product despite the limited evidence, follow the directions on the label exactly and never exceed them.

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

Read the full Holly 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 & Holly

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

0Major
0Moderate
0Minor
2,829No known interaction
2,829 No interaction
No interaction 2,829 drugs checked — show the list

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

Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Holly list.

See the full Holly interactions page
See every supplement checked against Insulin (rDNA), ranked by severity
Evidence & sources

Holly References

The 2 references that drive our Holly 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. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.

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 Holly and Insulin (rDNA) Together: Common Questions

Is it safe to take Holly with Insulin (rDNA)?
We do not list a known interaction between Holly 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 Holly 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 Holly 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.
Does Insulin (rDNA) interact with any supplements?
Yes. Insulin (rDNA) has documented interactions with 242 supplements in our database — Holly 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

Where next

Keep Exploring

Holly monograph Uses, safety profile, and every drug interaction in one place Insulin Lispro Injection drug information The full plain-English guide to this medication Insulin (rDNA) supplement interactions Every supplement checked against Insulin (rDNA), ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 2 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

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

Our pharmacists answer your medication & supplement questions — free.

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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.