Drug interactions
Heparin + Protamine
Severity: Moderate
Heparin and Protamine: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Protamine is a heparin antidote, not an additive anticoagulant. It binds heparin and neutralizes its effect, and at excess doses protamine itself can have weak anticoagulant activity. Rapid administration may cause hypotension or anaphylactoid reactions.
What this interaction means in plain words
Heparin and Protamine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Cationic protamine forms a stable complex with anionic heparin, inactivating it.
What to do
Dose protamine according to the amount of recent heparin given and infuse slowly with hemodynamic monitoring. Check aPTT or ACT to confirm reversal and avoid overdosing.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Heparin
- Defibrotide + Heparin Contraindicated
- Heparin + Ketorolac Contraindicated
- Heparin + Oritavancin Contraindicated
- Acemetacin + Heparin Major
- Acetylsalicylic acid + Heparin Major
- Alteplase + Heparin Major
Frequently asked questions
Can I take Heparin with Protamine?
MediHelp rates the interaction as moderate. Heparin and Protamine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Protamine is a heparin antidote, not an additive anticoagulant. It binds heparin and neutralizes its effect, and at excess doses protamine itself can have weak anticoagulant activity. Rapid administration may cause hypotension or anaphylactoid reactions.
How serious is the interaction between Heparin and Protamine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Dose protamine according to the amount of recent heparin given and infuse slowly with hemodynamic monitoring. Check aPTT or ACT to confirm reversal and avoid overdosing.
What other medicines interact with Heparin?
MediHelp also lists interactions of Heparin with, for example, Defibrotide, Ketorolac, Oritavancin. The full list is on the Heparin page.
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