Drug & supplement interaction

Job's Tears + Pembrolizumab

Pembrolizumab brand name: Keytruda.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Job's Tears and Pembrolizumab 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.

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Interaction report

Job's Tears and Pembrolizumab

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 Pembrolizumab and Job's Tears 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.

Job's Tears safety at a glance

Job's Tears overall Use caution Generally safe as a cooked food, but concentrated supplement evidence is limited.
Pregnancy Avoid Traditionally avoided in pregnancy and human safety data are lacking.
Breastfeeding Use caution Not enough reliable data; use only ordinary food amounts and check with a clinician.

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

Still wondering about combining Pembrolizumab and Job's Tears? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Pembrolizumab

Interactions in our licensed database are recorded against drug classes, not just single drug names. Pembrolizumab is filed under a single classification — antineoplastics. Job's Tears has documented interactions with 5 drug classes — the most serious being antidiabetes drugs (moderate), chlorzoxazone (parafon forte, paraflex) (moderate) and dextromethorphan (robitussin dm, others) (moderate) — and none of Pembrolizumab’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

Job's Tears Does Interact With Other Medications

Job's Tears has 128 moderate known drug interactions in our database — Pembrolizumab 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 Job's Tears

Covers the 2,830 medications we’ve checked against Job's Tears. Pick one to open its full report.

What to actually watch for

What Pembrolizumab’s Own FDA Label Lists

This is not an interaction — none of it involves Job's Tears. These are the most notable effects listed in the ADVERSE REACTIONS section of Pembrolizumab’s own FDA label, for the medication by itself. Knowing the drug’s own list makes it easier to work out the likely cause if something new turns up while you take both. 10 of them are worth acting on rather than waiting out — marked below.

  • Low magnesium Worth acting on
  • A change in thyroid levels Worth acting on
  • Trouble swallowing Worth acting on
  • High potassium Worth acting on
  • Low sodium Worth acting on
  • Low potassium Worth acting on
  • A heart attack Worth acting on
  • Blood clots Worth acting on
  • Heart failure Worth acting on
  • High blood sugar Worth acting on

Showing the 10 most notable of 57 label-listed effects — ranked by how unusual each one is across medicines generally, with serious effects weighted up.

From the ADVERSE REACTIONS section of the FDA label for Pembrolizumab. Read the label on DailyMed › Job's Tears’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Job's Tears side to compare — that is a limit of the record, not a statement that Job's Tears has no side effects.

Everything else you take

See Every Supplement That Interacts With Pembrolizumab

This page covers Job's Tears only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Pembrolizumab page lists 1 supplement it has a documented interaction with, worst first, each one explained.

The most serious there right now: American Pawpaw (minor).

By severity: 1 minor.

From our pharmacist’s overview on the Pembrolizumab page

“For a drug used against so many different cancers, pembrolizumab (Keytruda) has a remarkably short supplement file. Just one ingredient appears on it, American pawpaw, and even that lone entry is rated minor and judged unlikely to cause real trouble.”

Reviewed by 2 · Jul 18, 2026

Open the Pembrolizumab interaction page

One more smart check

Taking Job's Tears as Part of a Dietary Supplement Product? Check It for Interactions

We hold 111 real supplement products containing Job's Tears, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Job's Tears. Even though Job's Tears itself has no known interaction with Pembrolizumab, 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 Job's Tears and Pembrolizumab 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 Job's Tears
Top half

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

29 days ago today
Medication Pembrolizumab
Steady interest

#2,189 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 Job's Tears reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified October 4, 2026. The Job's Tears and Pembrolizumab records this page draws on were last updated July 11, 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 Job's Tears

What is Job's Tears?

  • Digestive support
  • Skin health and smoothness
  • Mild swelling or water retention
  • General nourishing food/tonic
  • Joint discomfort (traditional use)

Job's Tears is a grain-like seed long used as a food and in traditional medicine, especially in East Asia. While it is generally safe as a food and is being studied for possible effects on metabolism, inflammation, and immunity, strong human evidence for its health claims is limited. Talk with your pharmacist or doctor before using concentrated supplements, especially during pregnancy.

Coix lacryma-jobi · Poaceae · Seeds (grain/kernel), sometimes root · Whole grain, cooked food, tea, powder, capsules, flour

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

Job's Tears: dosing

There is no established standardized dose for Job's Tears as a supplement. As a food, it is simply cooked and eaten like other whole grains.For capsules, powders, or teas, follow the directions on the product label, since strengths vary widely between products.

From our Job's Tears monograph — the full record covers uses, side effects and every documented interaction.

Read the full Job's Tears monograph & all interactions
Medication

About Pembrolizumab Injection

What Is Pembrolizumab Injection Used For?

Brand name: Keytruda

Pembrolizumab Injection (Keytruda) is used to treat many types of cancer. Some uses are for cancer that has spread or can’t be removed by surgery. Others are given before or after surgery.

Main cancer types include melanoma, non-small cell lung cancer, mesothelioma, head and neck squamous cell cancer, classical Hodgkin lymphoma, urothelial (bladder) cancer, colorectal cancer, gastric and esophageal cancer, cervical cancer, liver cancer, biliary tract cancer, Merkel cell carcinoma, kidney cancer, endometrial cancer, cutaneous squamous cell carcinoma, triple-negative breast cancer and ovarian cancer. Many uses depend on tumor tests and are given alone or with other cancer drugs.

Most-Reported Side Effects for Pembrolizumab

From FAERS, the FDA’s public side-effect reporting system (0 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Malignant neoplasm progression 12,012 reports
Diarrhea 5,719 reports
Fatigue 5,113 reports
Fever 3,870 reports
Rash 3,719 reports
See full Pembrolizumab Injection drug information Pembrolizumab NDC codes and packages
Keep checking

Other Drugs & Job's Tears

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

0Major
128Moderate
0Minor
2,701No known interaction
Moderate

128 interactions

Showing 60 of 128 moderate interactions — see all 128 on the Job's Tears page.

No interaction 2,701 drugs checked — show the list
Evidence & sources

Job's Tears References

The 3 references that drive our Job's Tears 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. Chiang W, Cheng C, Chiang M, Chung KT. Effects of dehulled adlay on the culture count of some microbiota and their metabolism in the gastrointestinal tract of rats. J Agric Food Chem 2000;48:829-32. PubMed
  2. Yu YM, Chang WC, Liu CS, Tsai CM. Effect of young barley leaf extract and adlay on plasma lipids and LDL oxidation in hyperlipidemic smokers. Biol Pharm Bull 2004;27:802-5. PubMed
  3. Yao HT, Lin JH, Liu YT, Li ML, Chiang W. Food-Drug Interaction between the Adlay Bran Oil and Drugs in Rats. Nutrients 2019;11(10):2473. 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 Job's Tears and Pembrolizumab Together: Common Questions

Is it safe to take Job's Tears with Pembrolizumab?
We do not list a known interaction between Job's Tears and Pembrolizumab. 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.
How was the Job's Tears and Pembrolizumab combination checked?
Interactions in our licensed database are recorded against drug classes. Pembrolizumab is filed under 1 classification, and Job's Tears has documented interactions with 5 drug classes — none of Pembrolizumab'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 Job's Tears interact with any other medications?
Yes. Job's Tears has 128 documented drug interactions in our database — Pembrolizumab 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 Pembrolizumab interact with any supplements?
Yes. Pembrolizumab has documented interactions with 1 supplement in our database — Job's Tears is not one of them. The Pembrolizumab 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 Pembrolizumab and Job's Tears?

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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.