Drug & supplement interaction

Piracetam + Dalteparin

Dalteparin brand name: Fragmin.

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

Piracetam has a major interaction with Dalteparin. 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?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Piracetam and Dalteparin

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

Major

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Dalteparin

Dalteparin 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: Dalteparin (Fragmin) already thins your blood to keep dangerous clots from forming. Piracetam isn't a blood thinner itself, but some early research suggests it can make platelets (the tiny cells that help blood clot) a little less sticky. Stack that mild effect on top of dalteparin, and you may tip the scales toward easier bleeding.

What that can look like with dalteparin: more bruising, bleeding gums, nosebleeds, or, more seriously, blood in your urine or stool. I'll be honest, this concern is largely theoretical and based on limited studies, so it's not a sure thing. Still, since both affect clotting, please don't combine them without checking with your doctor or pharmacist first. They can watch you more closely if needed.

Contact Dr. Brian directly if you have additional questions on this interaction
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 Dalteparin one above is one of them. If you take anything else, check it against the full list below.

Major 121 No known interaction 2,709 (incl. Dalteparin)
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 Dalteparin

This page covers Piracetam only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dalteparin 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 Dalteparin page

“Dalteparin (Fragmin) is an injectable blood thinner used to prevent and treat dangerous clots, which is exactly why this list warrants real vigilance, and nearly all 218 ingredients on it thin the blood too. They are herbs and extracts with clot-inhibiting or antiplatelet effects of their own, so stacking them on dalteparin can push bl…”

Reviewed by 2 · Jul 18, 2026

Open the Dalteparin 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 Dalteparin 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 Dalteparin 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

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

29 days ago today
Medication Dalteparin
Top half

#865 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
Medication

About Dalteparin Injection

What Is Dalteparin Injection Used For?

Brand name: Fragmin

Fragmin (dalteparin) injection is used to prevent blood clots (deep vein thrombosis, or DVT) in people having hip replacement or abdominal surgery, and in hospitalized patients who are largely immobile due to acute illness. It is also used to reduce ischemic complications — meaning clot-related events — in people with unstable angina or a type of heart attack called non-Q-wave MI, when given alongside aspirin.

Fragmin is approved for the extended treatment of symptomatic venous thromboembolism (VTE — blood clots in the veins or lungs) in adults with cancer, to reduce the chance of clots coming back, for up to six months. It is also approved to treat symptomatic VTE in pediatric patients from birth (at least 35 weeks gestational age) onward. Fragmin is not intended for the acute (immediate emergency) treatment of VTE.

See full Dalteparin Injection drug information
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
121 Major 2,708 No 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

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

Showing the 60 most looked-up of 2,708 medications checked with no known interaction — see the full Piracetam list.

See the full Piracetam interactions page
See every supplement checked against Dalteparin, 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
Piracetam monograph › Uses, safety, and every drug interaction in one place Dalteparin supplement interactions › Every supplement checked against Dalteparin, ranked by severity Dalteparin Injection drug information › The full plain-English guide to this medication 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 Piracetam and Dalteparin Together: Common Questions

Can you take Piracetam with Dalteparin?
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 Dalteparin 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

Still Have a Question About Dalteparin and Piracetam?

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.