Drug & supplement interaction

Ketogenic Diet + Pentoxifylline

Pentoxifylline brand name: Trental.

Minor Interaction
The bottom line Minor

Ketogenic Diet has a minor interaction with Pentoxifylline. Although there is some concern that the ketogenic diet might have additive effects when used with anticoagulant and antiplatelet drugs, most clinical research does not show this effect.

Read the full interaction report
SeverityMinor
LikelihoodUnlikely
EvidenceB
What do Severity, Likelihood & Evidence mean?
Know someone interested in this? Share
Interaction report

Ketogenic Diet and Pentoxifylline

Here is the interaction we found between these two, with the evidence behind it.

Minor

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Pentoxifylline

Pentoxifylline falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Ketogenic Diet interacts with.

Although there is some concern that the ketogenic diet might have additive effects when used with anticoagulant and antiplatelet drugs, most clinical research does not show this effect.
One small observational study found that the ketogenic diet was associated with prolonged bleeding times in 16 of 51 (31%) children with epilepsy who were also on chronic anticonvulsant therapy. However, a larger observational study of 162 children with epilepsy taking chronic anticonvulsants has found that following the ketogenic diet does not increase the risk of bleeding, even in the 25 children undergoing surgery. Research in adults also has not reported changes in bleeding time.
Severity Minor Likelihood Unlikely Evidence B

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the bottom line on pairing a ketogenic diet with pentoxifylline (Trental): there's a small, mostly theoretical worry that both could nudge your blood toward easier bleeding. Pentoxifylline works by making your blood less thick so it flows better through small vessels, and the thinking is that keto might slightly add to that effect.

The good news is that the better research doesn't really back this up. One small study in children hinted at longer bleeding times, but a larger study (and adult data) found no meaningful change, even in kids having surgery. So this is a minor and unlikely concern, not a reason to panic. Still, watch for easy bruising, nosebleeds, or cuts that are slow to stop, and check with your pharmacist or doctor before starting keto.

References
  1. Melchior RW, Dreher M, Ramsey E, Savoca M, Rosenthal T. Cardiopulmonary bypass considerations for pediatric patients on the ketogenic diet. Perfusion. 2015;30(5):423-6. PubMed
  2. Dressler A, Chiara H, Benninger F, et al. Effects of the ketogenic diet on platelet counts and global coagulation tests in childhood epilepsy. Seizure. 2020;80:31-37. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Ketogenic Diet Also Interacts With Other Medications

Ketogenic Diet has 137 moderate, 121 minor known drug interactions in our database — the Pentoxifylline one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Ketogenic Diet

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

Everything else you take

See Every Supplement That Interacts With Pentoxifylline

This page covers Ketogenic Diet only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Pentoxifylline page lists 218 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Danshen (major), Piracetam (major), Aconite (moderate) and Allspice (moderate).

By severity: 3 major · 190 moderate · 25 minor.

From our pharmacist’s overview on the Pentoxifylline page

“Pentoxifylline (Trental) improves blood flow in people with poor leg circulation partly by making platelets less sticky, so treat this list as one to read carefully rather than skim. Of the 218 supplements on file, 202 can also slow clotting, which means adding them stacks bleeding risk on bleeding risk.”

Reviewed by 2 · Jul 18, 2026

Open the Pentoxifylline interaction page

How much people look this up

Where Ketogenic Diet and Pentoxifylline 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 Ketogenic Diet
Steady interest

#1,206 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Pentoxifylline
Top half

#862 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.

Eating pattern

About Ketogenic Diet

What is Ketogenic Diet?

  • Weight loss
  • Type 2 diabetes and blood sugar control
  • Drug-resistant epilepsy (especially in children)
  • Reducing appetite
  • Athletic and metabolic interest

The ketogenic diet is a very low-carbohydrate, high-fat eating plan that shifts the body to burn fat for fuel. It has the strongest evidence as a medical therapy for hard-to-treat epilepsy and may help short-term weight loss and blood sugar, but it can be hard to sustain and is not right for everyone. Talk with a doctor or pharmacist before starting, especially if you have a medical condition or take medication.

Read the full Ketogenic Diet monograph & all interactions
Medication

About Pentoxifylline

What Is Pentoxifylline Used For?

Brand name: Trental

Pentoxifylline Extended-Release Tablets are used to treat intermittent claudication — leg pain, cramping, or fatigue that happens during walking because narrowed arteries aren't delivering enough blood to the muscles. The underlying cause is chronic occlusive arterial disease, a condition where the arteries in the limbs become blocked or narrowed over time.

Pentoxifylline can help improve walking distance and reduce symptoms, but it is not a substitute for procedures that physically open or bypass blocked arteries when those treatments are needed.

See full Pentoxifylline drug information
Keep checking

Other Drugs & Ketogenic Diet

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

0Major
137Moderate
121Minor
2,571No known interaction
Moderate

137 interactions

Showing 60 of 137 moderate interactions — see all 137 on the Ketogenic Diet page.

Minor

121 interactions

Showing 60 of 121 minor interactions — see all 121 on the Ketogenic Diet page.

No interaction 2,571 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Keep exploring
Pharmacist Counseling Corner

Following Ketogenic Diet While Taking Pentoxifylline: Common Questions

Can you follow Ketogenic Diet while taking Pentoxifylline?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Ketogenic Diet and Pentoxifylline interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

Still Have a Question About Pentoxifylline and Ketogenic Diet?

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.