Drug & supplement interaction

Banana + Phenytoin

Phenytoin brand names: Dilantin Kapseals, Dilantin, Di-Phen, Dilantin Infatabs, Phenytek, and others.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Banana and Phenytoin 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 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

Banana and Phenytoin

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 Phenytoin and Banana 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.

Banana safety at a glance

Banana overall Generally safe Bananas are a common, generally safe food for most people when eaten in normal amounts.
Pregnancy Generally safe Bananas as a food are considered safe in pregnancy; concentrated supplements are less studied.
Breastfeeding Generally safe Bananas as a food are considered safe while breastfeeding.

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

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

Why No Interaction Is Listed for Phenytoin

Interactions in our licensed database are recorded against drug classes, not just single drug names. Phenytoin is filed under 14 classifications — including cytochrome p450 2c8 (cyp2c8) substrates, cytochrome p450 2c9 (cyp2c9) inducers, anticonvulsants. Banana has documented interactions with 1 drug class — the most serious being levodopa (moderate) — and none of Phenytoin’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

Banana Does Interact With Other Medications

Banana has 5 moderate known drug interactions in our database — Phenytoin 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 Banana

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

What to actually watch for

No Interaction Found — But Data Suggests Banana and Phenytoin 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. 3 of them are worth acting on rather than waiting out — marked below.

  • A severe allergic reaction / Hives Worth acting on Additional detail

    Banana

    “Orally, banana has been reported to cause allergic reaction, including urticaria and redness, abdominal pain and nausea, dyspnea, and anaphylaxis. Topically, contact urticara has also been reported. Skin testing is not always accurate, even for patients with severe banana allergy.”

    Banana · Natural Medicines adverse-effect record, reported in allergic rhinitis (hay fever).

    2 sources cited
    1. 93784. Meynadier J, Meynadier JM, Guilhou JJ. [Contact urticaria in atopic patients. Apropos of 2 cases]. Ann Dermatol Venereol. 1982;109(10):871-4.
    2. 93793. Hauswirth DW, Burks AW. Banana anaphylaxis with a negative commercial skin test. J Allergy Clin Immunol. 2005 Mar;115(3):632-3. PubMed

    Phenytoin

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

  • An allergic reaction Worth acting on Additional detail

    Banana

    Recorded for Banana in the same Natural Medicines adverse-effect record shown under A severe allergic reaction / Hives above.

    Phenytoin

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

  • Vomiting Additional detail

    Banana

    “Orally, banana starch isolated from green bananas has resulted in bloating, gas, cramping, and softer feces. When consumed prior to exercise, fullness and bloating during exercise have been reported. In children, nausea, vomiting, and abdominal distension have been reported when banana is used in the treatment of diarrhea.”

    Banana · Natural Medicines adverse-effect record, reported in diarrhea.

    6 sources cited
    1. 93448. Ble-Castillo JL, Aparicio-Trápala MA, Francisco-Luria MU, Córdova-Uscanga R, Rodríguez-Hernández A, Méndez JD, Díaz-Zagoya JC. Effects of native banana starch supplementation on body weight and insulin sensitivity in obese type 2 diabetics. Int J Environ PubMed
    2. 93449. Jiménez-Domínguez G, Ble-Castillo JL, Aparicio-Trápala MA, Juárez-Rojop IE, Tovilla-Zárate CA, Ble-Castillo DJ, García-Vázquez C, Olvera-Hernández V, Pérez-Pimienta B, Diaz-Zagoya JC, Mendez JD. Effects of Acute Ingestion of Native Banana Starch on Glycem
    3. 110619. Arias-Córdova Y, Ble-Castillo JL, García-Vázquez C, et al. Resistant Starch Consumption Effects on Glycemic Control and Glycemic Variability in Patients with Type 2 Diabetes: A Randomized Crossover Study. Nutrients 2021;13(11):4052. PubMed
    4. 93459. Nieman DC, Gillitt ND, Sha W, et al. Metabolomics-Based Analysis of Banana and Pear Ingestion on Exercise Performance and Recovery. J Proteome Res 2015;14(12):5367-77. doi: 10.1021/acs.jproteome.5b00909. PubMed
    5. 93461. Rabbani GH, Ahmed S, Hossain I, Islam R, Marni F, Akhtar M, Majid N. Green banana reduces clinical severity of childhood shigellosis: a double-blind, randomized, controlled clinical trial. Pediatr Infect Dis J. 2009 May;28(5):420-5. PubMed
    6. 93777. Schoeffl V, Varatorn R, Blinnikov O, Vidamaly V. Intestinal obstruction due to phytobezoars of banana seeds: a case report. Asian J Surg. 2004 Oct;27(4):348-51. PubMed

    Phenytoin

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

  • Nausea Additional detail

    Banana

    Recorded for Banana in the same Natural Medicines adverse-effect record shown under A severe allergic reaction / Hives above.

    Phenytoin

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

Reported for Banana but not commonly for Phenytoin: a bowel blockage, bloating or gas, stomach pain and high potassium.

Effects for Phenytoin come from the ADVERSE REACTIONS section of its FDA label; effects for Banana 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.

From our Q&A

Questions About Banana or Phenytoin

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

This page covers Banana only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Phenytoin page lists 224 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), Beer (major), Gamma-hydroxybutyrate (ghb) (major) and Kava (major).

By severity: 9 major · 187 moderate · 28 minor.

From our pharmacist’s overview on the Phenytoin page

“Phenytoin (Dilantin) is a seizure medicine with a narrow therapeutic index, meaning small changes in its blood level can bring seizures back or tip over into toxicity, so I treat its supplement list with real seriousness. The biggest group, 78 ingredients, piles on sedation, and alcohol, kava, and GHB all rate major for exactly that re…”

Reviewed by 2 · Jul 18, 2026

Open the Phenytoin interaction page

One more smart check

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

We hold 985 real supplement products containing Banana, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Banana. Even though Banana itself has no known interaction with Phenytoin, 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 Banana and Phenytoin 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 Banana
Top 25%

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

29 days ago today
Medication Phenytoin
Top 25%

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

What is Banana?

Banana
  • Source of potassium and energy
  • Digestive health and diarrhea
  • Blood pressure support
  • Heartburn and stomach ulcers (traditional)
  • Weight management

Bananas are a nutritious, widely eaten fruit that provide potassium, fiber, vitamin B6, and quick energy, and they are part of a healthy diet. While some traditional uses (like easing diarrhea or supporting blood pressure) have plausible support, most specific health claims are not strongly proven. For most people bananas are a safe food, but those with kidney problems or a latex-fruit allergy should be cautious.

Musa acuminata · Musaceae · Fruit (most common); peel, flower, and leaves are also used in some traditions · Fresh fruit, dried banana, banana powder, green (unripe) banana flour, smoothies

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

Banana: dosing

There is no official medicinal dose for bananas. As a food, one to a few bananas per day fits easily into a healthy diet for most people.For banana supplements, powders, or green banana flour, a standardized dose has not been established.

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

Read the full Banana monograph & all interactions
Medication

About Phenytoin

What Is Phenytoin Used For?

Brand names: Dilantin Kapseals, Dilantin, Di-Phen, Dilantin Infatabs, Phenytek, Dilantin injection

Phenytoin is used to treat and prevent seizures. The specific types covered depend on the formulation. Oral extended-release capsules (including Phenytek), chewable tablets (including Dilantin Infatabs and Phenytoin Infatabs), and oral suspension (including Dilantin-125) are used for tonic-clonic (grand mal) and psychomotor (temporal lobe) seizures; most oral forms also cover prevention and treatment of seizures occurring during or after neurosurgery. Chewable tablets and some capsule formulations also cover complex partial seizures.

Parenteral (injectable) phenytoin sodium is used for generalized tonic-clonic status epilepticus (a prolonged, life-threatening seizure emergency) and for prevention and treatment of seizures during neurosurgery. The IV form can also substitute short-term for oral phenytoin when a patient cannot take it by mouth.

Most-Reported Side Effects for Phenytoin

From FAERS, the FDA’s public side-effect reporting system (40,278 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Convulsion 3,522 reports
Seizure 3,095 reports
Toxicity to various agents 1,888 reports
Fall 1,604 reports
Dizziness 1,539 reports
See full Phenytoin drug information
Keep checking

Other Drugs & Banana

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

0Major
5Moderate
0Minor
2,824No known interaction
Moderate

5 interactions

No interaction 2,824 drugs checked — show the list
Evidence & sources

Banana References

The 11 references that drive our Banana 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. Ble-Castillo JL, Aparicio-Trápala MA, Francisco-Luria MU, Córdova-Uscanga R, Rodríguez-Hernández A, Méndez JD, Díaz-Zagoya JC. Effects of native banana starch supplementation on body weight and insulin sensitivity in obese type 2 diabetics. Int J Environ PubMed
  2. Jiménez-Domínguez G, Ble-Castillo JL, Aparicio-Trápala MA, Juárez-Rojop IE, Tovilla-Zárate CA, Ble-Castillo DJ, García-Vázquez C, Olvera-Hernández V, Pérez-Pimienta B, Diaz-Zagoya JC, Mendez JD. Effects of Acute Ingestion of Native Banana Starch on Glycem
  3. Nieman DC, Gillitt ND, Sha W, et al. Metabolomics-Based Analysis of Banana and Pear Ingestion on Exercise Performance and Recovery. J Proteome Res 2015;14(12):5367-77. doi: 10.1021/acs.jproteome.5b00909. PubMed
  4. Rabbani GH, Ahmed S, Hossain I, Islam R, Marni F, Akhtar M, Majid N. Green banana reduces clinical severity of childhood shigellosis: a double-blind, randomized, controlled clinical trial. Pediatr Infect Dis J. 2009 May;28(5):420-5. PubMed
  5. Schoeffl V, Varatorn R, Blinnikov O, Vidamaly V. Intestinal obstruction due to phytobezoars of banana seeds: a case report. Asian J Surg. 2004 Oct;27(4):348-51. PubMed
  6. Don M, Longo G. Food protein-induced enterocolitis syndrome due to banana: an uncommon entity. Eur Ann Allergy Clin Immunol. 2013 Apr;45(2):61-2.
  7. Tazoe M, Narita M, Sakuta R, Nagai T, Narita N. Hyperkalemia and hyperdopaminemia induced by an obsessive eating of banana in an anorexia nervosa adolescent. Brain Dev. 2007 Jul;29(6):369-72. PubMed
  8. Meynadier J, Meynadier JM, Guilhou JJ. [Contact urticaria in atopic patients. Apropos of 2 cases]. Ann Dermatol Venereol. 1982;109(10):871-4.
  9. Hauswirth DW, Burks AW. Banana anaphylaxis with a negative commercial skin test. J Allergy Clin Immunol. 2005 Mar;115(3):632-3. PubMed
  10. Hotozuka S, Yasu T, Hikita E, Shirota M. Interaction Between Levodopa and Banana in a Patient With Parkinson's Disease. Am J Ther 2022;29(4):465-467. PubMed
  11. Arias-Córdova Y, Ble-Castillo JL, García-Vázquez C, et al. Resistant Starch Consumption Effects on Glycemic Control and Glycemic Variability in Patients with Type 2 Diabetes: A Randomized Crossover Study. Nutrients 2021;13(11):4052. 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 Banana and Phenytoin Together: Common Questions

Is it safe to take Banana with Phenytoin?
We do not list a known interaction between Banana and Phenytoin. 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 Banana and Phenytoin have any of the same side effects?
Yes — our sources link each of them separately to 5 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.
How was the Banana and Phenytoin combination checked?
Interactions in our licensed database are recorded against drug classes. Phenytoin is filed under 14 classifications, and Banana has documented interactions with 1 drug class — none of Phenytoin'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 Banana interact with any other medications?
Yes. Banana has 5 documented drug interactions in our database — Phenytoin 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 Phenytoin interact with any supplements?
Yes. Phenytoin has documented interactions with 224 supplements in our database — Banana is not one of them. The Phenytoin 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 Phenytoin and Banana?

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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.