The short answer
A low-potassium interaction between Rheum undulatum and adagrasib has not been established. Other medicinal-rhubarb species are not equivalent; review the exact product with your oncology pharmacist.
What this answer covers
Oral Rheum undulatum products with oral adagrasib. Do not substitute evidence for R. palmatum, R. officinale, their hybrids or unidentified medicinal rhubarb.
- Supplement or preparation
- Rheum undulatum
- Medication ingredient
- adagrasib
The species name changes the evidence
The European medicinal-rhubarb assessment covers Rheum palmatum, Rheum officinale and their hybrids. This checker entry is Rheum undulatum. Laxative and electrolyte warnings for a different species cannot automatically establish the same interaction for your product.
The original comparison has an important limit
An experimental study found purgative activity for the tested R. palmatum preparation but not the tested R. undulatum preparation. It involved mice and laboratory work, not people taking adagrasib. The result challenges a blanket rhubarb assumption but does not prove that every R. undulatum product is safe.
Adagrasib still requires potassium attention
Krazati can cause digestive adverse effects and QT prolongation, and its label calls for potassium and magnesium assessment when indicated. Report persistent diarrhea or vomiting regardless of its cause. Your clinician can decide whether electrolyte tests or treatment are needed without assuming the herb caused the problem.
Check the actual contents before use
Show the oncology pharmacist the Latin name, plant part, preparation and any additional laxative ingredients. There is no established R. undulatum-specific risk estimate or protective spacing interval with adagrasib. Ask about an appropriate constipation plan instead of treating different rhubarb products as interchangeable.
Evidence and practical considerations
Side effects & toxicity
An increased low-potassium risk specifically from Rheum undulatum with adagrasib has not been established.
- Exact scope
- Oral Rheum undulatum products with oral adagrasib. Do not substitute evidence for R. palmatum, R. officinale, their hybrids or unidentified medicinal rhubarb. with Exact adagrasib RxCUI 2625882 IN, confirmed by current RxNorm properties. Oral Krazati tablets; the August 2026 U.S. label covers single-agent treatment of specified previously treated KRAS G12C-mutated NSCLC. Older cetuximab combination cohorts and regional label instructions are not interchangeable.
- Medication form and route
- Oral
What remains uncertain
- Common medicinal-rhubarb guidance covers different species. A nonclinical comparison found no purgative activity for the tested R. undulatum preparation, but cannot establish human safety or absence of potassium loss.
Factors that may matter: Exact preparation and dose; Treatment phase and duration; Liver function; Electrolyte results and GI symptoms; Other medicines.
Read the supporting source summaries
Source 1: Current U.S. prescribing information
bms.com · Source check Sep 10, 2026
Population: Adults with specified previously treated KRAS G12C-mutated locally advanced or metastatic non-small cell lung cancer.
Warns about GI toxicity, QT prolongation and hepatotoxicity. Monitor/correct electrolytes, particularly potassium and magnesium, and monitor liver tests. Strong CYP3A inducers lower exposure. Avoid strong CYP3A inhibitors until steady state, approximately eight days. High-fat meal did not meaningfully change exposure; tablets may be taken with or without food.
How this applies: Exact current U.S. guidance; newer than the retained March 2026 DailyMed version. Exact adagrasib RxCUI 2625882 IN, confirmed by current RxNorm properties. Oral Krazati tablets; the August 2026 U.S. label covers single-agent treatment of specified previously treated KRAS G12C-mutated NSCLC. Older cetuximab combination cohorts and regional label instructions are not interchangeable.
Not direct evidence of each botanical combination. Strong-inhibitor effects after a single dose differ from steady-state model predictions. Effects of adagrasib on other CYP substrates are a separate direction. No universal supplement prescription.
Source 2: Regulatory botanical assessment scope
ema.europa.eu · Source check Sep 10, 2026
Population: Users of medicinal rhubarb preparations.
Defines the species covered by the medicinal-rhubarb assessment; they are not R. undulatum.
How this applies: Documents the species mismatch underlying a common-name extrapolation.
Cannot transfer the covered species’ laxative or electrolyte risks directly to R. undulatum.
Source 3: Original nonclinical botanical study
kiss.kstudy.com · Source check Sep 10, 2026
Population: Mice and laboratory assays using human intestinal bacteria; not a human clinical trial.
R. palmatum had purgative activity in the reported model; the tested R. undulatum preparation did not.
How this applies: Counterevidence to assuming all rhubarb species have identical laxative activity.
Abstract-only nonclinical comparison. No human potassium outcome, no adagrasib and no basis to infer safety of every R. undulatum product.
Source 4: Authoritative medication terminology
rxnav.nlm.nih.gov · Source check Sep 10, 2026
Population: Medication terminology.
Identifies adagrasib as IN.
How this applies: Exact identity confirmation.
Not clinical interaction evidence.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Article prepared | |
| Sources checked and article drafted. | |
| Research summary published |
Article revision: 9ca61e2820c51de2
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.