Drug & supplement interaction

Quillaia + Eculizumab

Eculizumab brand name: Soliris.

Moderate Interaction
The bottom line Moderate

Quillaia has a moderate interaction with Eculizumab. Theoretically, concomitant use of quillaia with immunosuppressant drugs might decrease the effectiveness of these drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Quillaia and Eculizumab

Here is the interaction we found between these two, with the evidence behind it.

Moderate

IMMUNOSUPPRESSANTS

Why this applies to Eculizumab

Eculizumab falls under IMMUNOSUPPRESSANTS — the group Quillaia interacts with.

Theoretically, concomitant use of quillaia with immunosuppressant drugs might decrease the effectiveness of these drugs.
In vitro research shows that some quillaia constituents have immunostimulant effects.
Severity Moderate Likelihood Possible Evidence D

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.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the situation with quillaia and Soliris (eculizumab). Eculizumab is a lab-made antibody that works by quieting down a piece of your immune system (the complement pathway) to stop your body from attacking its own blood cells or nerves. It is not a prodrug and isn't processed by the liver enzymes that most herb interactions involve, so this isn't about quillaia changing your drug levels.

The concern is the opposite direction. In test-tube studies, certain quillaia saponins seem to stir up immune activity. Since eculizumab is meant to calm the immune system, a substance pushing the other way could, in theory, blunt how well it works. This is purely theoretical and based on lab data, not real patients, so I wouldn't panic. Still, with a serious condition like PNH or aHUS, run any quillaia supplement past your doctor or pharmacist first.

References
  1. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  3. Wu JY, Gardner BH, Murphy CI, et al. Saponin adjuvant enhancement of antigen-specific immune responses to an experimental HIV-1 vaccine. J Immunol 1992;148:1519-25. DOI
  4. Fleck JD, Betti AH, da Silva FP, et al. Saponins from Quillaja saponaria and Quillaja brasiliensis: particular chemical characteristics and biological activities. Molecules 2019;24(1). pii: E171. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction 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.
  • PossibleInteraction 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.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Quillaia Also Interacts With Other Medications

Quillaia has 120 moderate known drug interactions in our database — the Eculizumab one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Quillaia

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

Everything else you take

See Every Supplement That Interacts With Eculizumab

This page covers Quillaia only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Eculizumab page lists 53 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Active Hexose Correlated Compound (ahcc) (moderate), Alfalfa (moderate), American Ginseng (moderate), Andrographis (moderate) and Ashwagandha (moderate).

By severity: 52 moderate · 1 minor.

From our pharmacist’s overview on the Eculizumab page

“People prescribed eculizumab (Soliris) are usually managing a rare blood or nerve condition, and many of them reach for supplements marketed as immune boosters, things like echinacea, ginseng, or medicinal mushrooms. That instinct is exactly what this list is about.”

Reviewed by 2 · Jul 18, 2026

Open the Eculizumab interaction page

How much people look this up

Where Quillaia and Eculizumab 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 Quillaia
Top half

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

29 days ago today
Medication Eculizumab
Steady interest

#1,762 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.

Supplement

About Quillaia

What is Quillaia?

  • Cough and chest congestion
  • Foaming agent in beverages
  • Vaccine adjuvant (in pharmaceutical manufacturing)
  • Washing and cleansing (traditional soap)
  • Skin conditions

Quillaia (soap bark tree) is a plant whose bark contains foaming compounds called saponins, and it is widely used as an emulsifier in foods and drinks. As a supplement or herbal remedy its benefits are not well proven, and large amounts can be irritating or toxic, so it should be used cautiously and only as directed.

Read the full Quillaia monograph & all interactions
Medication

About Eculizumab Injection

What Is Eculizumab Injection Used For?

Brand name: Soliris

Soliris (eculizumab) injection is approved to treat four serious conditions: paroxysmal nocturnal hemoglobinuria (PNH), a rare blood disorder that causes red blood cell destruction; atypical hemolytic uremic syndrome (aHUS), a condition that causes abnormal blood clotting in small blood vessels; generalized myasthenia gravis (gMG), a neuromuscular disease causing muscle weakness; and neuromyelitis optica spectrum disorder (NMOSD), an inflammatory disease affecting the optic nerves and spinal cord.

For gMG, Soliris is approved for adults and children 6 years and older who test positive for anti-acetylcholine receptor (AChR) antibodies. For NMOSD, Soliris is approved for adults who test positive for anti-aquaporin-4 (AQP4) antibodies. Soliris is not indicated for hemolytic uremic syndrome caused by Shiga toxin-producing E. coli (STEC-HUS).

See full Eculizumab Injection drug information
Keep checking

Other Drugs & Quillaia

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

0Major
120Moderate
0Minor
2,709No known interaction
Moderate

120 interactions

Showing 60 of 120 moderate interactions — see all 120 on the Quillaia page.

No interaction 2,709 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

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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Pharmacist Counseling Corner

Taking Quillaia and Eculizumab Together: Common Questions

Can you take Quillaia with Eculizumab?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Quillaia and Eculizumab interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

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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.