Drug & supplement interaction

Arenaria Rubra + Cobicistat

Cobicistat brand name: Tybost.

No Known Interaction
Medically reviewed by · Updated June 2026 · Pair last verified Sep 13, 2026
The bottom line No known interaction

We found no known interaction between Arenaria Rubra and Cobicistat 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 Cobicistat states a food rule worth keeping to.

Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Arenaria Rubra and Cobicistat

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 Cobicistat and Arenaria Rubra 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.

Arenaria Rubra safety at a glance

Arenaria Rubra overall Not established Human safety data are very limited, so use cautiously and under professional guidance.
Pregnancy Avoid There is not enough safety information, so it is best avoided during pregnancy.
Breastfeeding Avoid Safety while breastfeeding is unknown, so avoid use to be safe.

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

Still wondering about combining Cobicistat and Arenaria Rubra? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Cobicistat

Interactions in our licensed database are recorded against drug classes, not just single drug names. Cobicistat is filed under 2 classifications — cytochrome p450 3a4 (cyp3a4) inhibitors, oral drugs. Arenaria Rubra has documented interactions with 1 drug class — the most serious being acetylcholinesterase (ache) inhibitors (moderate) — and none of Cobicistat’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

Arenaria Rubra Does Interact With Other Medications

Arenaria Rubra has 17 moderate known drug interactions in our database — Cobicistat isn’t one of them. If you take anything else, check it against the full list below.

Moderate 17 No known interaction 2,813 (incl. Cobicistat)
Taking anything else?

Check Another of Your Medications Against Arenaria Rubra

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

What to actually watch for

What Cobicistat’s Own FDA Label Lists

This is not an interaction — none of it involves Arenaria Rubra. These are the most notable effects listed in the ADVERSE REACTIONS section of Cobicistat’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. 7 of them are worth acting on rather than waiting out — marked below.

  • Kidney problems Worth acting on mentioned in 44.9% of FDA reports for Cobicistat
  • Kidney stones Worth acting on
  • Severe muscle breakdown Worth acting on
  • Yellowing of the skin or eyes Worth acting on
  • Low mood Worth acting on
  • Hives Worth acting on
  • An allergic reaction Worth acting on
  • Vivid dreams or nightmares
  • Trouble sleeping
  • Itching

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 Cobicistat. Read the label on DailyMed › Where a percentage is shown, it is the share of 20,779 voluntary FDA FAERS reports for Cobicistat that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Arenaria Rubra’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Arenaria Rubra side to compare — that is a limit of the record, not a statement that Arenaria Rubra has no side effects.

How to take them

Some Cobicistat Products Have a Food Rule — Arenaria Rubra Should Not Break It

At least one FDA label for a product containing Cobicistat says to take it with food. If you take Arenaria Rubra on an empty stomach out of habit, keep them separate — and take Cobicistat 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 Cobicistat 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.

2 DOSAGE AND ADMINISTRATION TYBOST must be coadministered with atazanavir or darunavir at the same time, with food, and in combination with other HIV-1 antiretroviral agents.

From the Dosage and Administration section of the FDA label we read for Cobicistat — 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.

Everything else you take

See Every Supplement That Interacts With Cobicistat

This page covers Arenaria Rubra only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Cobicistat page lists 30 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Adrafinil (moderate), Cannabidiol (cbd) (moderate), Cannabinol (cbn) (moderate) and Cannabis (moderate).

By severity: 1 major · 19 moderate · 10 minor.

From our pharmacist’s overview on the Cobicistat page

“Activated charcoal is the one entry to understand first if you take cobicistat (Tybost). Charcoal soaks up drugs in the gut, and since cobicistat's entire job is boosting an HIV medicine to protective levels, blunting its absorption can put the whole regimen at risk.”

Reviewed by 2 · Jul 18, 2026

Open the Cobicistat interaction page

How much people look this up

Where Arenaria Rubra and Cobicistat 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 Arenaria Rubra
Steady interest

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

29 days ago today
Medication Cobicistat
Top half

#1,209 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. Arenaria Rubra 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 Arenaria Rubra reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Arenaria Rubra and Cobicistat records this page draws on were last updated June 22, 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 Arenaria Rubra

What is Arenaria Rubra?

Arenaria Rubra
  • Urinary and bladder complaints
  • Kidney stones ("stone-breaking")
  • Mild diuretic
  • Traditional digestive support
  • Antioxidant interest

Arenaria rubra (Spergularia rubra) is a small herb used in folk medicine, mainly for urinary and kidney complaints. Modern evidence is very limited and comes mostly from laboratory studies, so its benefits in people are not proven. Talk with a pharmacist or doctor before using it, especially if you have a medical condition or are pregnant.

Spergularia rubra · Caryophyllaceae · Above-ground parts (aerial parts) · Tea (infusion), dried herb, liquid extracts

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

Arenaria Rubra: dosing

There is no established or standardized dose for Arenaria rubra. Reliable dosing studies in humans are lacking, so a safe and effective amount has not been defined.If you choose to use a commercial product, follow the directions on the label and do not exceed the recommended amount.

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

Read the full Arenaria Rubra monograph & all interactions
Medication

About Cobicistat

What Is Cobicistat Used For?

Brand name: Tybost

Tybost (cobicistat) is not itself an HIV treatment — it works by slowing the breakdown of certain HIV medicines so they stay active in your body long enough to work. Specifically, Tybost is used to boost the HIV medicines atazanavir or darunavir (once-daily dosing) as part of a complete HIV-1 treatment regimen in adults and in children weighing at least 14 kg (about 31 lbs).

Tybost is not interchangeable with ritonavir (another booster) for all HIV medicines. It is not recommended with darunavir twice-daily, fosamprenavir, saquinavir, or tipranavir.

Most-Reported Side Effects for Cobicistat

From FAERS, the FDA’s public side-effect reporting system (20,779 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Bone density decreased 8,112 reports
Chronic kidney disease 4,754 reports
Renal injury 4,577 reports
Tooth loss 4,186 reports
Bone loss 4,107 reports
See full Cobicistat drug information
Keep checking

Other Drugs & Arenaria Rubra

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

0Major
17Moderate
0Minor
2,812No known interaction
17 Moderate 2,812 No interaction
Moderate

17 interactions

No interaction 2,812 drugs checked — show the list

We also checked Arenaria Rubra against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,812 medications checked with no known interaction — see the full Arenaria Rubra list.

See the full Arenaria Rubra interactions page
See every supplement checked against Cobicistat, ranked by severity
Evidence & sources

Arenaria Rubra References

The 2 sources that drive our Arenaria Rubra monograph — publicly available pages from reputable medical and government organizations. Every link was verified to work before publishing. Arenaria Rubra is not covered by the licensed Natural Medicines interaction database, so its page cites these public sources directly.

  1. Using Dietary Supplements Wisely — NIH National Center for Complementary and Integrative Health Source
  2. Herbal Medicine — MedlinePlus (NIH) 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 Arenaria Rubra and Cobicistat Together: Common Questions

Is it safe to take Arenaria Rubra with Cobicistat?
We do not list a known interaction between Arenaria Rubra and Cobicistat. 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 Arenaria Rubra and Cobicistat at the same time of day?
At least one FDA label for a product containing Cobicistat says to take it with food. If you take Arenaria Rubra on an empty stomach out of habit, keep them separate and take Cobicistat with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Cobicistat products can differ — so check the directions on your own box. This is about absorption, not an interaction.
How was the Arenaria Rubra and Cobicistat combination checked?
Interactions in our licensed database are recorded against drug classes. Cobicistat is filed under 2 classifications, and Arenaria Rubra has documented interactions with 1 drug class — none of Cobicistat'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 Arenaria Rubra interact with any other medications?
Yes. Arenaria Rubra has 17 documented drug interactions in our database — Cobicistat 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 Cobicistat interact with any supplements?
Yes. Cobicistat has documented interactions with 30 supplements in our database — Arenaria Rubra is not one of them. The Cobicistat interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Arenaria Rubra monograph Uses, safety profile, and every drug interaction in one place Cobicistat drug information The full plain-English guide to this medication Cobicistat supplement interactions Every supplement checked against Cobicistat, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 2 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Cobicistat and Arenaria Rubra?

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.