Drug & supplement interaction

Diosmin + Diphenhydramine Hydrochloride, Naproxen Sodium

Diphenhydramine Hydrochloride, Naproxen Sodium brand name: Aleve PM.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Diphenhydramine Hydrochloride, Naproxen Sodium falls into 2 drug categories that Diosmin can interact with; the most serious is rated moderate. Theoretically, diosmin might inhibit the metabolism of CYP2C9 substrates.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Diosmin and Diphenhydramine Hydrochloride, Naproxen Sodium

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Diosmin interacts with whole categories of medication. Diphenhydramine Hydrochloride, Naproxen Sodium falls into 2 of those categories, so it can interact with Diosmin in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

1 of 2

Why this applies to Diphenhydramine Hydrochloride, Naproxen Sodium

Diphenhydramine Hydrochloride, Naproxen Sodium falls under CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES — the group Diosmin interacts with.

Theoretically, diosmin might inhibit the metabolism of CYP2C9 substrates.
Diclofenac is metabolized by CYP2C9 enzymes. Clinical and laboratory research shows that diosmin inhibits the metabolism of diclofenac. A pharmacokinetic study in humans shows that taking diosmin (Venex 500) 500 mg daily for 9 days prior to oral administration of diclofenac 100 mg increases blood levels of diclofenac and decreases diclofenac clearance.
Severity Moderate Likelihood Possible Evidence D

Interaction 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.

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

Aleve PM combines naproxen (an anti-inflammatory pain reliever) with diphenhydramine (the sleep aid in Benadryl). The naproxen part is partly cleared by a liver enzyme called CYP2C9. Diosmin may gently slow that enzyme down, so in theory naproxen could clear a little more slowly and build up slightly in your blood. That could mean a touch more of naproxen's usual effects, including stomach upset, heartburn, or a higher chance of stomach irritation with longer use.

I want to be honest though: this is a theoretical concern based on how the drugs are processed, plus one study with a different NSAID. It is not a dramatic or well-proven interaction. If you take Aleve PM only now and then, it is unlikely to be a big deal, but check with your pharmacist if you use it regularly.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Rajnarayana K, Venkatesham A, Krishna DR. Bioavailability of diclofenac sodium after pretreatment with diosmin in healthy volunteers. Drug Metabol Drug Interact. 2007;22(2-3):165-74. PubMed
  2. Poór M, Boda G, Mohos V, et al. Pharmacokinetic interaction of diosmetin and silibinin with other drugs: Inhibition of CYP2C9-mediated biotransformation and displacement from serum albumin. Biomed Pharmacother. 2018;102:912-921. PubMed
Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

2 of 2

Diphenhydramine Hydrochloride, Naproxen Sodium also falls under ANTICOAGULANT/ANTIPLATELET DRUGS.

Theoretically, diosmin may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
A case of spontaneous intraventricular hemorrhage has been reported for a 77-year-old female after 6 weeks of warfarin therapy, despite an international normalized ratio (INR) of only 1.8. The patient had also been taking aspirin and diosmin for several years. Experts speculate that chronic intake of diosmin predisposed the patient to spontaneous intraventricular hemorrhage by inducing chronic microcirculatory hypertension and inhibiting platelet aggregation. The presence of aspirin was also thought to play a role in this event.
Severity Moderate Likelihood Possible Evidence D

Interaction 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.

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

Aleve PM pairs naproxen, an anti-inflammatory pain reliever, with diphenhydramine, an antihistamine that helps you sleep. The piece that matters here is the naproxen. Like other NSAIDs, naproxen already nudges up bleeding risk because it can irritate the stomach lining and make platelets a little less sticky. Diosmin may gently add to that platelet effect, so in theory the two together could raise the chance of bruising or bleeding more than either alone.

To be fair, this is weak, anecdotal evidence, mostly tied to a single case where someone was also on warfarin and aspirin. For occasional Aleve PM use it is unlikely to cause trouble. Still, if you notice easy bruising, black stools, or stomach pain, or you take this often, check with your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Kumar RM, Van Gompel JJ, Bower R, Rabinstein AA. Spontaneous intraventricular hemorrhage associated with prolonged diosmin therapy. Neurocrit Care. 2011 Jun;14(3):438-40. 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

Diosmin Also Interacts With Other Medications

Diosmin has 883 moderate known drug interactions in our database — the Diphenhydramine Hydrochloride, Naproxen Sodium one above is among them. If you take anything else, check it against the full list below.

Moderate 883 No known interaction 1,947 (incl. Diphenhydramine Hydrochloride, Naproxen Sodium)
Taking anything else?

Check Another of Your Medications Against Diosmin

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

Everything else you take

See Every Supplement That Interacts With Diphenhydramine Hydrochloride, Naproxen Sodium

This page covers Diosmin only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Diphenhydramine Hydrochloride, Naproxen Sodium page lists 378 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), Asarabacca (major), Beer (major) and Danshen (major).

By severity: 13 major · 320 moderate · 45 minor.

From our pharmacist’s overview on the Diphenhydramine Hydrochloride, Naproxen Sodium page

“Aleve PM combines naproxen, an NSAID, with the sedating antihistamine diphenhydramine, and its supplement list earns genuine care rather than a quick skim. Thirteen of the 378 ingredients on file rate major, and the two largest themes track the pill's two halves.”

Reviewed by 2 · Jul 18, 2026

Open the Diphenhydramine Hydrochloride, Naproxen Sodium interaction page

One more smart check

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

We hold 121 real supplement products containing Diosmin, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Diosmin. Your product may carry other ingredients that interact with Diphenhydramine Hydrochloride, Naproxen Sodium too, on top of Diosmin — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Diosmin and Diphenhydramine Hydrochloride, Naproxen Sodium 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 Diosmin
Top half

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

29 days ago today
Medication Diphenhydramine Hydrochloride, Naproxen Sodium
Top 25%

#663 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.

Supplement

About Diosmin

What is Diosmin?

  • Chronic venous insufficiency
  • Hemorrhoids
  • Leg swelling and heaviness
  • Varicose veins
  • Spider veins

Diosmin is a citrus-derived flavonoid most often used for vein-related problems such as chronic venous insufficiency and hemorrhoids, and it is usually combined with a related flavonoid called hesperidin. Some studies suggest it may help relieve leg swelling and hemorrhoid symptoms, but quality varies. Talk to your pharmacist or doctor before starting it, especially if you are pregnant or breastfeeding.

Read the full Diosmin monograph & all interactions
Keep checking

Other Drugs & Diosmin

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

0Major
883Moderate
0Minor
1,946No known interaction
883 Moderate 1,946 No interaction
Moderate

883 interactions

Showing 60 of 883 moderate interactions — see all 883 on the Diosmin page.

No interaction 1,946 drugs checked — show the list

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

Showing the 60 most looked-up of 1,946 medications checked with no known interaction — see the full Diosmin list.

See the full Diosmin interactions page
See every supplement checked against Diphenhydramine Hydrochloride, Naproxen Sodium, ranked by severity
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
Diosmin monograph › Uses, safety, and every drug interaction in one place Diphenhydramine Hydrochloride, Naproxen Sodium supplement interactions › Every supplement checked against Diphenhydramine Hydrochloride, Naproxen Sodium, 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 Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Diosmin and Diphenhydramine Hydrochloride, Naproxen Sodium Together: Common Questions

Can you take Diosmin with Diphenhydramine Hydrochloride, Naproxen Sodium?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
Why are there 2 interactions listed for Diosmin and Diphenhydramine Hydrochloride, Naproxen Sodium?
Diphenhydramine Hydrochloride, Naproxen Sodium belongs to more than one drug category, and Diosmin interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Diosmin and Diphenhydramine Hydrochloride, Naproxen Sodium interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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.