Drug & supplement interaction

Spinach + Glycerol Phenylbutyrate

Glycerol Phenylbutyrate brand name: Ravicti.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 20, 2026
The bottom line No known interaction

We found no known interaction between Spinach and Glycerol Phenylbutyrate 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 Glycerol Phenylbutyrate states a food rule worth keeping to, and the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Spinach and Glycerol Phenylbutyrate

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 Glycerol Phenylbutyrate and Spinach 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.

Spinach safety at a glance

Spinach overall Generally safe Spinach is safe and nutritious as a food for most people.
Pregnancy Likely Safe When used in amounts commonly found in foods; avoid medicinal amounts. Read the full pregnancy detail
Breastfeeding Likely Safe When used in amounts commonly found in foods; avoid medicinal amounts. Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Glycerol Phenylbutyrate and Spinach? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Glycerol Phenylbutyrate

Interactions in our licensed database are recorded against drug classes, not just single drug names. Glycerol Phenylbutyrate is filed under a single classification — oral drugs. Spinach has documented interactions with 2 drug classes — the most serious being antidiabetes drugs (moderate) and warfarin (coumadin) (moderate) — and none of Glycerol Phenylbutyrate’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

Spinach Does Interact With Other Medications

Spinach has 88 moderate known drug interactions in our database — Glycerol Phenylbutyrate isn’t one of them. If you take anything else, check it against the full list below.

Moderate 88 No known interaction 2,742 (incl. Glycerol Phenylbutyrate)
Taking anything else?

Check Another of Your Medications Against Spinach

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

What to actually watch for

No Interaction Found — But Data Suggests Spinach and Glycerol Phenylbutyrate May Share a Side Effect

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do.

  • A skin rash Additional detail

    Spinach

    “Topically, contact dermatitis has been reported from spinach in a 54-year-old female farmer.”

    Spinach · Natural Medicines adverse-effect record, reported in dermatitis.

    1 source cited
    1. 41757. Roller, E., Meller, S., Homey, B., Ruzicka, T., and Neumann, N. J. [Contact dermatitis caused by spinach, hedge mustard and chives]. Hautarzt 2003;54(4):374-375.

    Glycerol Phenylbutyrate

    Listed in the ADVERSE REACTIONS section of the FDA label for Glycerol Phenylbutyrate. Read the label on DailyMed ›

Reported for Spinach but not commonly for Glycerol Phenylbutyrate: wheezing.

Effects for Glycerol Phenylbutyrate come from the ADVERSE REACTIONS section of its FDA label; effects for Spinach come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 1,358 voluntary FDA FAERS reports for Glycerol Phenylbutyrate that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Spinach in Pregnancy & Breastfeeding

Pregnancy And Lactation Likely Safe

When used in amounts commonly found in foods; avoid medicinal amounts.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

How to take them

Some Glycerol Phenylbutyrate Products Have a Food Rule — Spinach Should Not Break It

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

Instruct patients to take glycerol phenylbutyrate oral liquid with food or formula and to administer directly into the mouth via oral syringe.

From the Dosage and Administration section of the FDA label we read for Glycerol Phenylbutyrate — 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 Glycerol Phenylbutyrate

This page covers Spinach only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Glycerol Phenylbutyrate page lists 17 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Coffee Charcoal (moderate), European Mandrake (moderate), Glucomannan (moderate) and Guar Gum (moderate).

By severity: 1 major · 7 moderate · 9 minor.

From our pharmacist’s overview on the Glycerol Phenylbutyrate page

“Ravicti (glycerol phenylbutyrate) pulls ammonia out of the blood in people with urea cycle disorders, so a dose that never gets absorbed is not a small problem, it can let ammonia climb toward dangerous levels. That is why this list deserves real attention even though it is short.”

Reviewed by 2 · Jul 18, 2026

Open the Glycerol Phenylbutyrate interaction page

One more smart check

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

We hold 3,925 real supplement products containing Spinach, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Spinach. Even though Spinach itself has no known interaction with Glycerol Phenylbutyrate, 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 Spinach and Glycerol Phenylbutyrate 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 Spinach
Top 10%

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

29 days ago today
Medication Glycerol Phenylbutyrate
Top 10%

#192 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 Spinach reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Spinach and Glycerol Phenylbutyrate 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 Spinach

What is Spinach?

  • General nutrition and antioxidant support
  • Eye health
  • Heart health and blood pressure
  • Athletic performance
  • Constipation and digestive support

Spinach is a nutrient-dense leafy green that is a healthy part of a balanced diet, providing vitamins, minerals, fiber, and antioxidants. While it is very safe as a food, concentrated supplements and extracts are far less studied, and most specific health claims are not strongly proven. People prone to kidney stones or taking blood thinners should be mindful of its oxalate and vitamin K content.

Spinacia oleracea · Amaranthaceae · Leaves · Fresh or cooked leaves, powders, juice, capsules, and extracts

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

Spinach: dosing

There is no official standardized dose for spinach. As a food, it can be enjoyed in normal serving sizes as part of a balanced diet.For supplements such as powders, capsules, or extracts, a proven dose has not been established. More is not always better, especially given spinach's oxalate and vitamin K content.

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

Read the full Spinach monograph & all interactions
Medication

About Glycerol Phenylbutyrate

What Is Glycerol Phenylbutyrate Used For?

Brand name: Ravicti

Glycerol phenylbutyrate oral liquid — available as the brand Ravicti and as a generic — is used for the long-term (chronic) management of urea cycle disorders (UCDs). UCDs are rare inherited conditions where the body cannot properly convert ammonia into urea, causing toxic ammonia levels to build up in the blood and brain.

It is used in patients whose ammonia cannot be controlled by a low-protein diet and/or amino acid supplements alone. It must always be used alongside dietary protein restriction and, in some cases, additional dietary supplements such as essential amino acids, arginine, or citrulline. It is not for treating a sudden, severe spike in ammonia (acute hyperammonemia), and its safety and effectiveness for N-acetylglutamate synthase (NAGS) deficiency have not been established.

Most-Reported Side Effects for Glycerol Phenylbutyrate

From FAERS, the FDA’s public side-effect reporting system (1,358 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Ammonia increased 197 reports
Vomiting 165 reports
Hyperammonaemia 158 reports
Decreased appetite 104 reports
Nausea 74 reports
See full Glycerol Phenylbutyrate drug information
Keep checking

Other Drugs & Spinach

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

0Major
88Moderate
0Minor
2,741No known interaction
88 Moderate 2,741 No interaction
Moderate

88 interactions

Showing 60 of 88 moderate interactions — see all 88 on the Spinach page.

No interaction 2,741 drugs checked — show the list

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

Showing the 60 most looked-up of 2,741 medications checked with no known interaction — see the full Spinach list.

See the full Spinach interactions page
See every supplement checked against Glycerol Phenylbutyrate, ranked by severity
Evidence & sources

Spinach References

The 6 references that drive our Spinach 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. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  2. Karlson, B., Leijd, B., and Hellstrom, K. On the influence of vitamin K-rich vegetables and wine on the effectiveness of warfarin treatment. Acta Med Scand. 1986;220(4):347-350. PubMed
  3. Roller, E., Meller, S., Homey, B., Ruzicka, T., and Neumann, N. J. [Contact dermatitis caused by spinach, hedge mustard and chives]. Hautarzt 2003;54(4):374-375.
  4. Schuller, A., Morisset, M., Maadi, F., Kolopp Sarda, M. N., Fremont, S., Parisot, L., Kanny, G., and Moneret-Vautrin, D. A. Occupational asthma due to allergy to spinach powder in a pasta factory. Allergy 2005;60(3):408-409. PubMed
  5. Gustafsson, K., Asp, N. G., Hagander, B., and Nyman, M. Satiety effects of spinach in mixed meals: comparison with other vegetables. Int.J.Food Sci.Nutr. 1995;46(4):327-334. PubMed
  6. Schreiber, J., Muller, E., Becker, W. M., Zabel, P., Schlaak, M., and Amthor, M. [Spinach powder-induced exogenous allergic alveolitis]. Pneumologie 1998;52(1):61-65.

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 Spinach and Glycerol Phenylbutyrate Together: Common Questions

Is it safe to take Spinach with Glycerol Phenylbutyrate?
We do not list a known interaction between Spinach and Glycerol Phenylbutyrate. 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.
Do Spinach and Glycerol Phenylbutyrate have any of the same side effects?
Yes — our sources link each of them separately to one of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Should I take Spinach and Glycerol Phenylbutyrate at the same time of day?
At least one FDA label for a product containing Glycerol Phenylbutyrate says to take it with food. If you take Spinach on an empty stomach out of habit, keep them separate and take Glycerol Phenylbutyrate with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Glycerol Phenylbutyrate products can differ — so check the directions on your own box. This is about absorption, not an interaction.
How was the Spinach and Glycerol Phenylbutyrate combination checked?
Interactions in our licensed database are recorded against drug classes. Glycerol Phenylbutyrate is filed under 1 classification, and Spinach has documented interactions with 2 drug classes — none of Glycerol Phenylbutyrate'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 Spinach interact with any other medications?
Yes. Spinach has 88 documented drug interactions in our database — Glycerol Phenylbutyrate 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 Glycerol Phenylbutyrate interact with any supplements?
Yes. Glycerol Phenylbutyrate has documented interactions with 17 supplements in our database — Spinach is not one of them. The Glycerol Phenylbutyrate 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

Spinach monograph Uses, safety profile, and every drug interaction in one place Glycerol Phenylbutyrate drug information The full plain-English guide to this medication Glycerol Phenylbutyrate supplement interactions Every supplement checked against Glycerol Phenylbutyrate, 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 6 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Glycerol Phenylbutyrate and Spinach?

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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.