Drug & supplement interaction

Spinach + Quinine

Quinine brand name: Qualaquin.

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

We found no known interaction between Spinach and Quinine 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 Quinine 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 Quinine

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 Quinine 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 Quinine and Spinach? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Quinine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Quinine is filed under 5 classifications — including cytochrome p450 3a4 (cyp3a4) inhibitors, photosensitizing drugs, cytochrome p450 3a4 (cyp3a4) substrates. Spinach has documented interactions with 2 drug classes — the most serious being antidiabetes drugs (moderate) and warfarin (coumadin) (moderate) — and none of Quinine’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 — Quinine 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. Quinine)
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 Quinine May Share Several of the Same Side Effects

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. One of them is worth acting on rather than waiting out — marked below.

  • Wheezing Worth acting on Additional detail

    Spinach

    “Lung inflammation associated with allergic alveolitis has been reported after inhalation of spinach powder. The powder has also been reported to induce occupational asthma in a spinach factory worker.”

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

    2 sources cited
    1. 75871. 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.
    2. 75833. 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

    Quinine

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

  • 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.

    Quinine

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

Effects for Quinine come from the ADVERSE REACTIONS section of its FDA label; effects for Spinach come from the Natural Medicines adverse-effect record, quoted above. 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 Quinine Products Have a Food Rule — Spinach Should Not Break It

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

Quinine sulfate capsules should be taken with food to minimize gastric upset [see Clinical Pharmacology (12.3) ] .

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

From our Q&A

Questions About Spinach or Quinine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Spinach or Quinine, 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 Quinine

This page covers Spinach only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Quinine page lists 175 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Cinchona (major), Foxglove (major), Grapefruit (major) and Lily-of-the-valley (major).

By severity: 9 major · 125 moderate · 41 minor.

From our pharmacist’s overview on the Quinine page

“Quinine (Qualaquin) earns a genuine pause before you add any supplement, because nine of its 175 interacting ingredients are rated major, and two are as everyday as grapefruit and St. John's wort.”

Reviewed by 2 · Jul 18, 2026

Open the Quinine 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 Quinine, 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 Quinine 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%

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

29 days ago today
Medication Quinine
Steady interest

#2,070 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 13, 2026. The Spinach and Quinine 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 Quinine

What Is Quinine Used For?

Brand name: Qualaquin

Quinine sulfate capsules (brands Qualaquin and Quinine Sulfate) are approved to treat uncomplicated Plasmodium falciparum malaria in adults. This includes strains of malaria that have become resistant to chloroquine.

Quinine sulfate capsules are not approved for severe or complicated malaria, for preventing malaria, or for treating or preventing nocturnal leg cramps. Using them for leg cramps carries serious risks that outweigh any potential benefit.

See full Quinine 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 Quinine, 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 Quinine Together: Common Questions

Is it safe to take Spinach with Quinine?
We do not list a known interaction between Spinach and Quinine. 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 Quinine have any of the same side effects?
Yes — our sources link each of them separately to 2 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 Quinine at the same time of day?
At least one FDA label for a product containing Quinine says to take it with food. If you take Spinach on an empty stomach out of habit, keep them separate and take Quinine with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Quinine products can differ — so check the directions on your own box. This is about absorption, not an interaction.
How was the Spinach and Quinine combination checked?
Interactions in our licensed database are recorded against drug classes. Quinine is filed under 5 classifications, and Spinach has documented interactions with 2 drug classes — none of Quinine'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 — Quinine 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 Quinine interact with any supplements?
Yes. Quinine has documented interactions with 175 supplements in our database — Spinach is not one of them. The Quinine 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 Quinine drug information The full plain-English guide to this medication Quinine supplement interactions Every supplement checked against Quinine, 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 Quinine 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.