Drug & supplement interaction

Piracetam + Lepirudin

Lepirudin brand name: Refludan.

Major Interaction
The bottom line Major

Piracetam has a major interaction with Lepirudin. Theoretically, concomitant use of piracetam and anticoagulant/antiplatelet drugs might increase the risk of bleeding.

Read the full interaction report
SeverityMajor
LikelihoodProbable
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Piracetam and Lepirudin

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

Major

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Lepirudin

Lepirudin falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Piracetam interacts with.

Theoretically, concomitant use of piracetam and anticoagulant/antiplatelet drugs might increase the risk of bleeding.
Preliminary clinical research shows that a single dose of piracetam inhibits platelet aggregation.
Severity Major Likelihood Probable Evidence B

Interaction 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..

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

Here's the short version: Lepirudin (Refludan) is a powerful injectable blood thinner given in the hospital, usually for people who can't take heparin. It works by directly blocking thrombin, a key player in clotting. Piracetam doesn't change how lepirudin is broken down, but research suggests piracetam can make platelets (the cells that help form clots) a bit less sticky on their own.

Stack a platelet-slowing effect on top of an already strong anticoagulant and you could tip the scales toward easier bruising, nosebleeds, or harder-to-stop bleeding. This is partly theoretical, but the bleeding concern with lepirudin is real and serious. Since lepirudin is hospital-managed, your care team should know about any piracetam use. Please don't combine these without talking to your doctor or pharmacist first.

References
  1. Moriau M, Crasborn L, Lavenne-Pardonge E, et al. Platelet anti-aggregant and rheological properties of piracetam. A pharmacodynamic study in normal subjects. Arzneimittelforschung. 1993;43(2):110-8.

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

Piracetam Also Interacts With Other Medications

Piracetam has 121 major, known drug interactions in our database — the Lepirudin 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 Piracetam

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

Everything else you take

See Every Supplement That Interacts With Lepirudin

This page covers Piracetam only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Lepirudin 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), Aconite (moderate), Allspice (moderate) and Aloe (moderate).

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

From our pharmacist’s overview on the Lepirudin page

“Lepirudin (Refludan) is a potent injectable blood thinner, typically given when heparin has caused a dangerous platelet reaction, and that makes this a list to read with real care. Of the 218 supplements and herbs with interactions on file, 202 can slow clotting on their own, piling extra bleeding risk onto a drug whose chief hazard is…”

Reviewed by 2 · Jul 18, 2026

Open the Lepirudin interaction page

One more smart check

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

We hold 6 real supplement products containing Piracetam, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Piracetam. Your product may carry other ingredients that interact with Lepirudin too, on top of Piracetam — 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 Piracetam and Lepirudin 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 Piracetam
Steady interest

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

29 days ago today
Medication Lepirudin
Steady interest

#2,463 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 Piracetam

What is Piracetam?

  • Memory and cognition ('nootropic')
  • Cognitive decline and dementia
  • Myoclonus
  • Dyslexia in children
  • Vertigo

Piracetam is a synthetic 'nootropic' drug studied mainly for cognitive decline, myoclonus, and certain neurological conditions, but evidence for boosting memory in healthy people is weak. It is a prescription medicine in many countries and is not an approved drug or dietary supplement in the United States, so quality and safety of products sold online vary. Talk to a doctor or pharmacist before using it.

Read the full Piracetam monograph & all interactions
Keep checking

Other Drugs & Piracetam

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

121Major
0Moderate
0Minor
2,708No known interaction
Major

121 interactions

Showing 60 of 121 major interactions — see all 121 on the Piracetam page.

No interaction 2,708 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

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Pharmacist Counseling Corner

Taking Piracetam and Lepirudin Together: Common Questions

Can you take Piracetam with Lepirudin?
This is rated a major interaction, so the combination is best avoided unless your doctor or pharmacist has specifically told you otherwise. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Piracetam and Lepirudin interaction?
We rate it Major. This is a clinically significant combination that is generally best avoided, or used only under the direct supervision of your physician or pharmacist.

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.