Heparin and Tenecteplase: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Heparin
No brand names on recordTenecteplase
No brand names on record
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
An increased risk of bleeding
Interaction Deep Dive
Concomitant use of an anticoagulant with a fibrinolytic (eg, thrombolytic) agent may increase the risk of major bleeding events due to additive effects1. Two studies have demonstrated safe coadministration of low-dose 4 or low-intensity warfarin therapy (ie, INR of 1.7 or less) with a thrombolytic agent 5. However, if concomitant use of an anticoagulant with a fibrinolytic agent is required, patients should be monitored clinically for signs and symptoms of external or internal bleeding. Laboratory monitoring is also advised 2. Closely observe surgical wound drainage. If Hb levels fall, or if there is a decrease in blood pressure, bleeding should be suspected 3.
Why it happens (mechanism)
Additive effects
Literature reports
3 reports — tap to read
a) In clinical trials in patients undergoing percutaneous transluminal coronary angioplasty (PTCA) or percutaneous coronary intervention (PCI), coadministration of bivalirudin with thrombolytic agents, glycoprotein IIb/IIIa inhibitors, warfarin, or heparin was associated with increased risks of major bleeding events when compared with patients not receiving these concomitant medications 1. Any agent that may enhance the risk of hemorrhage should be discontinued prior to initiation of desirudin therapy 2.
b) Although lower doses were used during streptokinase infusion, warfarin administration did not present any problems, according to a Finnish study that evaluated the use of streptokinase with oral anticoagulants in the treatment of DVT. Forty-four patients initially received warfarin 0.5 mg and streptokinase 600,000 international units. Streptokinase 600,000 international units/hour was continued for 3 days and phlebography was performed to evaluate clearing of the thrombotic occlusion. Treatment was continued for a further 3 days if lysis was incomplete. When necessary, warfarin was given to keep the protein phosphatase (PP) activity level 0.1 to 0.2. Hemorrhage was the reason for the discontinuation of treatment in 8 of the 44 patients (18.2%). Although this study documents concomitant use of oral anticoagulants and streptokinase, both the anticoagulant and streptokinase were initiated at the same time. Since 3 to 5 days is required before hypoprothrombinemia is obtained, these patients did not experience the true interaction of the thrombolytic effect of streptokinase resulting in hypoprothrombinemia due to the concomitant use of warfarin 4.
c) In a study analyzing registry data of 45,074 patients who received IV tissue plasminogen activator for acute ischemic stroke, there was no significant increase in the risk for symptomatic intracerebral hemorrhage or death in patients on warfarin therapy with an INR of 1.7 or less (n=768) compared with patients not treated with warfarin (n=43,651) after adjusting for age, stroke severity, and comorbidities 5.
Common questions
Can I take Heparin and Tenecteplase together?
An increased risk of bleeding Always confirm with your pharmacist or prescriber before making any change.
How serious is the Heparin and Tenecteplase interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Heparin or Tenecteplase need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (5)
- Product Information: ANGIOMAX(R) IV injection, bivalirudin IV injection. The Medicines Company, Parsippany, NJ, 2005.
- Product Information: Iprivask(TM), desirudin for injection. Aventis Pharmaceuticals Inc. Bridgewater, NJ, 2003.
- Product Information: Xarelto(R) oral film-coated tablets, rivaroxaban oral film-coated tablets. Bayer HealthCare (per manufacturer), Leverkusen, Germany, 2008. DailyMed
- Jarvinen P, Aromaa U, Roiha M, et al: Streptokinase and concomitant oral anticoagulants in the treatment of deep venous thrombosis. Klin Wochenschr 1978; 56:801-804. PubMed
- Mazya MV, Lees KR, Markus R, et al: Safety of intravenous thrombolysis for ischemic stroke in patients treated with warfarin. Ann Neurol 2013; 74(2):266-274. PubMed
Keep reading about Heparin
Keep reading about Tenecteplase
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