Hydroxymethylbutyrate (hmb) + Pentoxifylline
Pentoxifylline brand name: Trental.
We found no known interaction between Hydroxymethylbutyrate (hmb) and Pentoxifylline 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 Pentoxifylline 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.
Hydroxymethylbutyrate (hmb) and Pentoxifylline
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 Pentoxifylline and Hydroxymethylbutyrate (hmb) 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.
Worth understanding: our licensed dataset holds no drug-interaction record for Hydroxymethylbutyrate (hmb) at all — not against Pentoxifylline, and not against any other medication we track. This verdict therefore rests on the absence of any recorded data, not on research that looked at this combination and found nothing. We cannot rule an interaction out.
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.
Hydroxymethylbutyrate (hmb) safety at a glance
Safety guidance is general; always confirm with your pharmacist or doctor for your situation.
Some Pentoxifylline Products Have a Food Rule — Hydroxymethylbutyrate (hmb) Should Not Break It
At least one FDA label for a product containing Pentoxifylline says to take it with food. If you take Hydroxymethylbutyrate (hmb) on an empty stomach out of habit, keep them separate — and take Pentoxifylline 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 Pentoxifylline 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.
DOSAGE AND ADMINISTRATION The usual dosage of pentoxifylline in extended-release tablet form is one tablet (400 mg) three times a day with meals.
From the Dosage and Administration section of the FDA label we read for Pentoxifylline — 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.
See Every Supplement That Interacts With Pentoxifylline
This page covers Hydroxymethylbutyrate (hmb) 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
Where Hydroxymethylbutyrate (hmb) 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.
#1,412 of 1,452 supplements looked up here in the last 7 days
#1,342 of 2,830 medications looked up here in the last 7 days
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 Hydroxymethylbutyrate (hmb) reference on this page ↓
- Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Hydroxymethylbutyrate (hmb) and Pentoxifylline 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.
About Hydroxymethylbutyrate (hmb)
What is Hydroxymethylbutyrate (hmb)?
- Building or preserving muscle mass
- Improving strength with resistance training
- Reducing muscle breakdown
- Supporting recovery after exercise
- Preventing muscle loss in older adults or illness
HMB is a compound made in the body from the amino acid leucine and is sold as a supplement mainly to support muscle. The best evidence suggests it may help slow muscle loss in certain situations, such as during illness, bed rest, or aging, but results in healthy athletes are mixed. It appears generally well tolerated for most adults, but you should check with your pharmacist or doctor before starting it.
Not applicable (HMB is a metabolite of the amino acid leucine) · Capsules, tablets, powder, drink mixes; available as calcium-HMB (CaHMB) and free-acid HMB
An interaction check asks whether these two react with each other — it does not ask whether Hydroxymethylbutyrate (hmb) is a good idea for someone in your situation. Here is what our Hydroxymethylbutyrate (hmb) record says about it on its own.
Hydroxymethylbutyrate (hmb): dosing
There is no single official dose of HMB, and the best amount depends on the goal and the person. Most research has used HMB taken in divided doses across the day, often alongside resistance training or protein intake.The two common forms are calcium-HMB and free-acid HMB, which may be absorbed differently.
From our Hydroxymethylbutyrate (hmb) monograph — the full record covers uses, side effects and every documented interaction.
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.
Most-Reported Side Effects for Pentoxifylline
From FAERS, the FDA’s public side-effect reporting system (4,300 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.
Other Drugs & Hydroxymethylbutyrate (hmb)
Browse every other medication we’ve checked against Hydroxymethylbutyrate (hmb) — both the ones with a known interaction and the ones without. Select any drug for the full detail.
No drugs match “”.
No interaction 2,829 drugs checked — show the list
We also checked Hydroxymethylbutyrate (hmb) against these medications and found no known interaction in our sources. Open any page to confirm.
- Apixaban ›
- Levothyroxine ›
- Amlodipine ›
- Methylphenidate ›
- Warfarin ›
- Sertraline ›
- Losartan Potassium ›
- Testosterone ›
- Ivermectin ›
- Abemaciclib ›
- Metoprolol ›
- Aspirin ›
- Acetaminophen ›
- Rosuvastatin ›
- Rivaroxaban ›
- Escitalopram ›
- Clopidogrel ›
- Atorvastatin ›
- Tadalafil ›
- Docusate ›
- Tirzepatide ›
- Ibuprofen ›
- Methamphetamine ›
- Hydroxyurea ›
- Warfarin Sodium ›
- Valacyclovir ›
- Sumatriptan ›
- Semaglutide ›
- Prednisone ›
- Lisdexamfetamine ›
- Propranolol ›
- Metformin ›
- Lisinopril ›
- Amitriptyline ›
- Amoxicillin ›
- Isotretinoin ›
- Methotrexate ›
- Amlodipine Besylate ›
- Bendamustine ›
- Bupropion ›
- Amphetamine ›
- Fluoxetine ›
- Doxycycline ›
- Acyclovir ›
- Azithromycin ›
- Lamotrigine ›
- Pregabalin ›
- Dextroamphetamine ›
- Gabapentin ›
- Acetaminophen, Codeine ›
- Quetiapine ›
- Clonazepam ›
- Levothyroxine, Liothyronine ›
- Naproxen ›
- Omeprazole ›
- Letrozole ›
- Methylene Blue ›
- Duloxetine ›
- Citalopram ›
- Buspirone ›
Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Hydroxymethylbutyrate (hmb) list.
Hydroxymethylbutyrate (hmb) References
The 3 references that drive our Hydroxymethylbutyrate (hmb) 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.
- Berton L, Bano G, Carraro S, et al. Effect of oral beta-hydroxy-beta-methylbutyrate (HMB) supplementation on physical performance in healthy old women over 65 years: An open label randomized controlled trial. PLoS One. 2015;10(11):e0141757. PubMed
- Tritto AC, Bueno S, Rodrigues RMP, Gualano B, Roschel H, Artioli GG. Negligible effects of ß-hydroxy-ß-methylbutyrate free acid and calcium salt on strength and hypertrophic responses to resistance training: a randomized, placebo-controlled study. Int J S PubMed
- Osuka Y, Kojima N, Sasai H, et al. Effects of exercise and/or ß-hydroxy-ß-methylbutyrate supplementation on muscle mass, muscle strength, and physical performance in older women with low muscle mass: a randomized, double-blind, placebo-controlled trial. A 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.
Taking Hydroxymethylbutyrate (hmb) and Pentoxifylline Together: Common Questions
Is it safe to take Hydroxymethylbutyrate (hmb) with Pentoxifylline?
Do Hydroxymethylbutyrate (hmb) and Pentoxifylline have any of the same side effects?
Should I take Hydroxymethylbutyrate (hmb) and Pentoxifylline at the same time of day?
Does Pentoxifylline interact with any supplements?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
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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.