Drug & supplement interaction

Agar + Ceritinib

Ceritinib brand name: Zykadia.

Minor Interaction
The bottom line Minor

Agar has a minor interaction with Ceritinib. Agar forms a thick gel, which may disrupt the absorption of nutrients and medications.

Read the full interaction report
SeverityMinor
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Interaction report

Agar and Ceritinib

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

Minor

ORAL DRUGS

Why this applies to Ceritinib

Ceritinib falls under ORAL DRUGS — the group Agar interacts with.

Agar forms a thick gel, which may disrupt the absorption of nutrients and medications. Animal research suggests that consuming a diet consisting of 5% to 10% agar alters the absorption of nutrients from the diet. In one study, consuming a diet composed of 10% agar reduced the absorption of all evaluated minerals. Theoretically, agar may also impair the absorption of oral drugs.
Severity Minor 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 simple version: agar is a seaweed fiber that swells into a thick gel in your stomach and gut. Because it's bulky and traps things, the worry is that it could grab onto a pill like Ceritinib (Zykadia) as it passes through, so a little less of the drug gets absorbed into your body. Ceritinib works directly as it is, it doesn't need your body to activate it, so the concern here is simply getting too little, not too much.

I want to be honest about how soft this evidence is. It comes from animal studies using diets that were 5 to 10 percent agar, not from people taking cancer medicines. Small amounts of agar in food are unlikely to matter. Still, since Ceritinib fights cancer and steady levels count, please run any agar supplement past your oncologist or pharmacist first, and don't take them at the same time of day.

References
  1. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  2. 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.
  3. 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

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

Agar Also Interacts With Other Medications

Agar has 2,021 minor known drug interactions in our database — the Ceritinib 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 Agar

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

Everything else you take

See Every Supplement That Interacts With Ceritinib

This page covers Agar only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ceritinib page lists 67 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), Arsenic (major), Beer (major) and Cesium (major).

By severity: 10 major · 48 moderate · 9 minor.

From our pharmacist’s overview on the Ceritinib page

“Ceritinib (Zykadia) treats ALK-positive lung cancer, and its label already warns about liver injury and heart rhythm changes, so this list of 67 supplements calls for genuine care. Ten interactions rate major, and most of the risk runs along two lines the drug is already prone to: 38 ingredients can stress the liver, and 13 can prolong…”

Reviewed by 2 · Jul 18, 2026

Open the Ceritinib 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. Your product may carry other ingredients that interact with Ceritinib too, on top of Agar — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Agar and Ceritinib 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

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

29 days ago today
Medication Ceritinib
Steady interest

#2,243 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 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.

Read the full Agar monograph & all interactions
Medication

About Ceritinib

What Is Ceritinib Used For?

Brand name: Zykadia

Zykadia (ceritinib) is used to treat adults with metastatic non-small cell lung cancer (NSCLC) — meaning lung cancer that has spread — when the tumor tests positive for a gene abnormality called ALK (anaplastic lymphoma kinase). An FDA-approved test must confirm ALK positivity before starting treatment.

See full Ceritinib 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
2,021Minor
808No known interaction
Minor

2,021 interactions

Showing 60 of 2,021 minor interactions — see all 2,021 on the Agar page.

No interaction 808 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 808 medications checked with no known interaction — see the full Agar 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

Keep exploring
Pharmacist Counseling Corner

Taking Agar and Ceritinib Together: Common Questions

Can you take Agar with Ceritinib?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Agar and Ceritinib interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

Still Have a Question About Ceritinib and Agar?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.