Drug & supplement interaction

Gras + Obinutuzumab

Obinutuzumab brand name: Gazyva.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Gras and Obinutuzumab 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 Obinutuzumab states a food rule worth keeping to.

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Interaction report

Gras and Obinutuzumab

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 Obinutuzumab and Gras 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 Gras at all — not against Obinutuzumab, 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.

Gras safety at a glance

Gras overall Not established We cannot confirm what "Gras" is, so its safety is unknown.
Pregnancy Avoid Because the product is unidentified, avoid it during pregnancy unless a doctor confirms it is safe.
Breastfeeding Avoid With no reliable information, avoid it while breastfeeding unless cleared by your doctor.

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

Still wondering about combining Obinutuzumab and Gras? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

What Obinutuzumab’s Own FDA Label Lists

This is not an interaction — none of it involves Gras. These are the most notable effects listed in the ADVERSE REACTIONS section of Obinutuzumab’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.

  • High potassium Worth acting on
  • Low sodium Worth acting on
  • Low potassium Worth acting on
  • A low platelet count Worth acting on
  • Kidney problems Worth acting on
  • Anemia Worth acting on
  • A low white blood cell count Worth acting on
  • Liver problems Worth acting on
  • A higher chance of infection Worth acting on
  • An allergic reaction Worth acting on

Showing the 10 most notable of 17 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 Obinutuzumab. Read the label on DailyMed › Gras’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Gras side to compare — that is a limit of the record, not a statement that Gras has no side effects.

How to take them

Some Obinutuzumab Products Have a Food Rule — Gras Should Not Break It

At least one FDA label for a product containing Obinutuzumab says to take it on an empty stomach. Most supplements — Gras included — are taken with a meal, so the easy mistake is swallowing both together at breakfast. Where that rule applies, keep Obinutuzumab on its own and move Gras to a meal later in the day.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Obinutuzumab 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.

650–1,000 mg acetaminophen At least 30 minutes before GAZYVA infusion.

From the Dosage and Administration section of the FDA label we read for Obinutuzumab — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›

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.

How much people look this up

Where Gras and Obinutuzumab 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 Gras
Steady interest

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

29 days ago today
Medication Obinutuzumab
Steady interest

#1,955 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. Gras is not yet covered by that licensed database, so its write-up cites publicly available medical sources directly (see the references below).
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Gras reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Gras and Obinutuzumab records this page draws on were last updated June 20, 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 Gras

What is Gras?

We could not find reliable information about a dietary supplement or herb called "Gras." The name may be a misspelling, a brand name, or a local/regional term, so we cannot confirm what it is, what it does, or whether it is safe. Please double-check the name with your pharmacist or the product label before using it.

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

Gras: dosing

There is no established or recommended dose for "Gras" because the product cannot be reliably identified. We will not guess an amount. If you have a labeled product, follow the manufacturer's instructions only after confirming the actual ingredient with a pharmacist or doctor.

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

Read the full Gras monograph & all interactions
Medication

About Obinutuzumab Injection

What Is Obinutuzumab Injection Used For?

Brand name: Gazyva

Gazyva is used to treat three conditions. For chronic lymphocytic leukemia (CLL), it is given in combination with chlorambucil in patients who have not been treated before. For follicular lymphoma (FL), it is used either with bendamustine (for patients whose disease came back or stopped responding to a rituximab-based regimen) or with chemotherapy (for previously untreated advanced disease) — in both cases followed by Gazyva alone as maintenance therapy.

Gazyva is also approved for active lupus nephritis — a type of kidney inflammation caused by lupus — in adults who are already receiving standard therapy for the condition.

See full Obinutuzumab Injection drug information
Keep checking

Other Drugs & Gras

Browse every other medication we’ve checked against Gras — 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
No interaction 2,829 drugs checked — show the list
Evidence & sources

Gras References

The 3 sources that drive our Gras monograph — publicly available pages from reputable medical and government organizations. Every link was verified to work before publishing. Gras is not covered by the licensed Natural Medicines interaction database, so its page cites these public sources directly.

  1. Dietary and Herbal Supplements — NIH NCCIH Source
  2. Herbs and Supplements — MedlinePlus Source
  3. Generally Recognized as Safe (GRAS) — U.S. Food and Drug Administration Source

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 Gras and Obinutuzumab Together: Common Questions

Is it safe to take Gras with Obinutuzumab?
We do not list a known interaction between Gras and Obinutuzumab. 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 Gras and Obinutuzumab at the same time of day?
At least one FDA label for a product containing Obinutuzumab says to take it on an empty stomach, and supplements are usually taken with a meal — so taking them together at breakfast is the easy mistake. Where that applies, keep Obinutuzumab on its own and move Gras to a meal later in the day. Food instructions belong to the product rather than the ingredient, so check the directions on your own box. This is about absorption, not an interaction.

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

Still Have a Question About Obinutuzumab and Gras?

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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.