Drug & supplement interaction

Chaga + Ritonavir

Ritonavir brand name: Norvir.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Chaga and Ritonavir 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 Ritonavir states a food rule worth keeping to.

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Interaction report

Chaga and Ritonavir

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 Ritonavir and Chaga 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.

Chaga safety at a glance

Chaga overall Use caution Generally used in foods and teas, but human safety data are limited and a few risks have been reported.
Pregnancy Avoid Not enough safety information; best to avoid during pregnancy.
Breastfeeding Avoid Not enough safety information; best to avoid while breastfeeding.

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

Still wondering about combining Ritonavir and Chaga? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Ritonavir

Interactions in our licensed database are recorded against drug classes, not just single drug names. Ritonavir is filed under 10 classifications — including protease inhibitors (pis), cytochrome p450 1a2 (cyp1a2) inducers, cytochrome p450 2d6 (cyp2d6) inhibitors. Chaga has documented interactions with 3 drug classes — the most serious being anticoagulant/antiplatelet drugs (moderate), antidiabetes drugs (moderate) and immunosuppressants (moderate) — and none of Ritonavir’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

Chaga Does Interact With Other Medications

Chaga has 327 moderate known drug interactions in our database — Ritonavir 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 Chaga

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

What to actually watch for

What Chaga Itself Has Been Linked To

This is not an interaction — nothing below involves Ritonavir. It is the side-effect record for Chaga on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Chaga, this list is the first place to look. One entry is worth acting on rather than waiting out — marked below.

  • Kidney problems Worth acting on Additional detail

    “Orally, there have been two cases of kidney failure and one case of acute nephropathy related to excessive chaga consumption, which contains high concentrations of oxalate.”

    Chaga · Natural Medicines adverse-effect record, reported in kidney failure.

    3 sources cited
    1. 96566. Kikuchi Y, Seta K, Ogawa Y, et al. Chaga mushroom-induced oxalate nephropathy. Clin Nephrol 2014;81(6):440-4. PubMed
    2. 105246. Lee S, Lee HY, Park Y, et al. Development of end stage renal disease after long-term ingestion of chaga mushroom: case report and review of literature. J Korean Med Sci. 2020;35(19):e122.
    3. 108756. Kwon O, Kim Y, Paek JH, et al. Chaga mushroom-induced oxalate nephropathy that clinically manifested as nephrotic syndrome: A case report. Medicine (Baltimore) 2022;101(10):e28997. PubMed

Everything above comes from the Natural Medicines adverse-effect record for Chaga — expand a row for the licensed statement it rests on. We read the ADVERSE REACTIONS section of Ritonavir’s FDA label too, and the two lists don’t meaningfully overlap — which is why no Ritonavir column appears here.

How to take them

Some Ritonavir Products Have a Food Rule — Chaga Should Not Break It

At least one FDA label for a product containing Ritonavir says to take it with food. If you take Chaga on an empty stomach out of habit, keep them separate — and take Ritonavir with a meal where the label says to.

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

The bitter aftertaste of NORVIR oral powder may be lessened if administered with food.

From the Dosage and Administration section of the FDA label we read for Ritonavir — where that label names a specific product, the instruction is that product's. See the Ritonavir drug page ›

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.

From our Q&A

Questions About Chaga or Ritonavir

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Chaga or Ritonavir, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Ritonavir

This page covers Chaga only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ritonavir page lists 178 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Grapefruit (major), Siberian Cocklebur (major) and St. John's Wort (major).

By severity: 6 major · 136 moderate · 36 minor.

From our pharmacist’s overview on the Ritonavir page

“If you take ritonavir (Norvir), slow down before adding any supplement from this page. Six of the 178 ingredients here carry a major rating, and St.”

Reviewed by 2 · Jul 18, 2026

Open the Ritonavir interaction page

One more smart check

Taking Chaga as Part of a Dietary Supplement Product? Check It for Interactions

We hold 889 real supplement products containing Chaga, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Chaga. Even though Chaga itself has no known interaction with Ritonavir, 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 Chaga and Ritonavir 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 Chaga
Top 25%

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

29 days ago today
Medication Ritonavir
Steady interest

#1,948 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 Chaga reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Chaga and Ritonavir records this page draws on were last updated July 10, 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 Chaga

What is Chaga?

  • Immune support
  • Antioxidant support
  • General wellness/tonic
  • Blood sugar support
  • Inflammation

Chaga is a fungus that grows mostly on birch trees and is used as a tea or supplement, mainly for immune and antioxidant support. Human evidence for its benefits is very limited, and it may raise some safety concerns such as effects on blood sugar, bleeding, and kidney stones. Talk with your pharmacist or doctor before using it, especially if you have a health condition or take other medicines.

Inonotus obliquus · Hymenochaetaceae · Sclerotium (the dark, hardened growth on the tree) · Tea, powder, capsules, tinctures, liquid extracts

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

Chaga: dosing

There is no standardized or officially established dose for Chaga. The amount in supplements and teas varies widely depending on the product and how it is prepared.The safest approach is to follow the directions on the product label and not exceed the recommended amount.

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

Read the full Chaga monograph & all interactions
Medication

About Ritonavir

What Is Ritonavir Used For?

Brand name: Norvir

Ritonavir (brand name Norvir) is used together with other HIV medicines to treat HIV-1 infection in adults and children older than one month of age. It is always taken as part of a combination regimen — never on its own.

Norvir oral powder is specifically indicated for pediatric patients with HIV-1 infection. Norvir tablets and oral solution are indicated for both adults and pediatric patients with HIV-1 infection. Ritonavir tablets (generic) are also indicated for the treatment of HIV-1 infection in combination with other antiretroviral agents.

Most-Reported Side Effects for Ritonavir

From FAERS, the FDA’s public side-effect reporting system (94,560 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Covid-19 23,011 reports
Disease recurrence 20,169 reports
Dysgeusia 7,508 reports
Diarrhea 5,704 reports
Nausea 4,358 reports
See full Ritonavir drug information
Keep checking

Other Drugs & Chaga

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

0Major
327Moderate
0Minor
2,502No known interaction
Moderate

327 interactions

Showing 60 of 327 moderate interactions — see all 327 on the Chaga page.

No interaction 2,502 drugs checked — show the list
Evidence & sources

Chaga References

The 9 references that drive our Chaga 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. Sun JE, Ao ZH, Lu ZM, et al. Antihyperglycemic and antilipidperoxidative effects of dry matter of culture broth of Inonotus obliquus in submerged culture on normal and alloxan-diabetes mice. J Ethnopharmacol 2008;118(1):7-13. PubMed
  2. Hyun KW, Jeong SC, Lee DH, et al. Isolation and characterization of a novel platelet aggregation inhibitory peptide from the medicinal mushroom, Inonotus obliquus. Peptides 2006;27(6):1173-8. PubMed
  3. Kim YO, Han SB, Lee HW, et al. Immuno-stimulating effect of the endo-polysaccharide produced by submerged culture of Inonotus obliquus. Life Sci 2005;77(19):2438-56. PubMed
  4. Kikuchi Y, Seta K, Ogawa Y, et al. Chaga mushroom-induced oxalate nephropathy. Clin Nephrol 2014;81(6):440-4. PubMed
  5. Lee S, Lee HY, Park Y, et al. Development of end stage renal disease after long-term ingestion of chaga mushroom: case report and review of literature. J Korean Med Sci. 2020;35(19):e122.
  6. Kwon O, Kim Y, Paek JH, et al. Chaga mushroom-induced oxalate nephropathy that clinically manifested as nephrotic syndrome: A case report. Medicine (Baltimore) 2022;101(10):e28997. PubMed
  7. Su L, Xin C, Yang J, et al. A polysaccharide from Inonotus obliquus ameliorates intestinal barrier dysfunction in mice with type 2 diabetes mellitus. Int J Biol Macromol 2022;214:312-323. PubMed
  8. Chen S, Ma Y, Li H, et al. Anti-diabetic e?ects of Inonotus obliquus extract in high fat diet combined streptozotocin-induced type 2 diabetic mice. Nutr Hosp 2022;39(6):1256-1263. PubMed
  9. Ye X, Wu K, Xu L, et al. Methanol extract of Inonotus obliquus improves type 2 diabetes mellitus through modifying intestinal flora. Front Endocrinol (Lausanne) 2023;13:1103972. 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 Chaga and Ritonavir Together: Common Questions

Is it safe to take Chaga with Ritonavir?
We do not list a known interaction between Chaga and Ritonavir. 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 Chaga and Ritonavir at the same time of day?
At least one FDA label for a product containing Ritonavir says to take it with food. If you take Chaga on an empty stomach out of habit, keep them separate and take Ritonavir with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Ritonavir products can differ — so check the directions on your own box. This is about absorption, not an interaction.
How was the Chaga and Ritonavir combination checked?
Interactions in our licensed database are recorded against drug classes. Ritonavir is filed under 10 classifications, and Chaga has documented interactions with 3 drug classes — none of Ritonavir'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 Chaga interact with any other medications?
Yes. Chaga has 327 documented drug interactions in our database — Ritonavir 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 Ritonavir interact with any supplements?
Yes. Ritonavir has documented interactions with 178 supplements in our database — Chaga is not one of them. The Ritonavir 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 Ritonavir and Chaga?

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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.