Skip to main content

Protamine Sulfate

Generic: PROTAMINE SULFATE

Verified·Apr 23, 2026
NDC
63323-229
ICD-10 indication
T45.511A

Affordability Check

How much will you actually pay for Protamine Sulfate?

In 30 seconds, see every legitimate way to afford Protamine Sulfate — Medicare copay, manufacturer copay card, Patient Assistance Program, grants, or cash.

Check my options →

About Protamine Sulfate

What is this medication? Protamine sulfate is a prescription medication primarily used to neutralize the anticoagulant effects of heparin. It is typically administered in medical settings when a person has received too much heparin or when the blood-thinning effects of heparin need to be stopped quickly, such as after cardiac surgery or during certain vascular procedures. By binding directly with heparin molecules, it forms a stable salt complex that effectively prevents the heparin from continuing to inhibit the natural blood clotting process. In addition to reversing standard heparin, protamine sulfate is sometimes used to counteract the effects of low molecular weight heparins, though its neutralizing capacity for those specific drugs may be less complete. The medication is usually delivered by slow intravenous injection under the direct supervision of healthcare professionals to ensure patient safety and monitor for potential side effects like low blood pressure. It is considered an essential reversal agent for managing bleeding risks and restoring normal coagulation when heparin therapy is no longer required or becomes dangerous.

Copay & patient assistance

Detailed copay and financial assistance information is not publicly available for this medication at this time. Please consult your pharmacist or the manufacturer's official patient support program for more details.

External links go directly to the manufacturer's portal. RxCopays does not receive compensation for referrals.

Compare pricing elsewhere

RxCopays doesn't sell drugs or take referral fees. Here are the transparent-pricing directories we recommend checking alongside your insurance formulary.

We deep-link because transparency helps patients. None of these partners pay RxCopays.

Prescribing information

From the FDA-approved label for Protamine Sulfate. Official source: DailyMed (NLM) · Label effective Mar 18, 2024

Boxed warning
WARNING Protamine sulfate can cause severe hypotension, cardiovascular collapse, noncardiogenic pulmonary edema, catastrophic pulmonary vasoconstriction, and pulmonary hypertension. Risk factors include high dose or overdose, rapid administration (see WARNINGS and DOSAGE AND ADMINISTRATION ), repeated doses, previous administration of protamine, and current or previous use of protamine-containing drugs (NPH insulin, protamine zinc insulin, and certain beta-blockers). Allergy to fish, previous vasectomy, and severe left ventricular dysfunction and abnormal preoperative pulmonary hemodynamics also may be risk factors. In patients with any of these risk factors, the risk to benefit of administration of protamine sulfate should be carefully considered. Vasopressors and resuscitation equipment should be immediately available in case of a severe reaction to protamine. Protamine sulfate should not be given when bleeding occurs without prior heparin use.
Indications and usage
INDICATIONS AND USAGE: Protamine Sulfate Injection, USP is indicated in the treatment of heparin overdosage.
Dosage and administration
DOSAGE AND ADMINISTRATION: Each mg of protamine sulfate, calculated on the dried basis, neutralizes not less than 100 USP Heparin Units. Protamine sulfate injection should be given by very slow intravenous injection over a 10-minute period in doses not to exceed 50 mg (see WARNINGS ). Protamine sulfate is intended for injection without further dilution; however, if further dilution is desired, D5-W or normal saline may be used. Diluted solutions should not be stored since they contain no preservative. Protamine sulfate should not be mixed with other drugs without knowledge of their compatibility, because protamine sulfate has been shown to be incompatible with certain antibiotics, including several of the cephalosporins and penicillins. Because heparin disappears rapidly from the circulation, the dose of protamine sulfate required also decreases rapidly with the time elapsed following intravenous injection of heparin. For example, if the protamine sulfate is administered 30 minutes after the heparin, one-half the usual dose may be sufficient. The dosage of protamine sulfate should be guided by blood coagulation studies (see WARNINGS ). Parenteral drug products should be visually inspected for particulate matter and discoloration prior to administration, whenever solution and container permit.
Contraindications
CONTRAINDICATIONS: Protamine sulfate is contraindicated in patients who have shown previous intolerance to the drug.
Warnings
WARNINGS: Hyperheparinemia or bleeding has been reported in experimental animals and in some patients 30 minutes to 18 hours after cardiac surgery (under cardiopulmonary bypass) in spite of complete neutralization of heparin by adequate doses of protamine sulfate at the end of the operation. It is important to keep the patient under close observation after cardiac surgery. Additional doses of protamine sulfate should be administered if indicated by coagulation studies, such as the heparin titration test with protamine and the determination of plasma thrombin time. Too-rapid administration of protamine sulfate can cause severe hypotensive and anaphylactoid reactions (see DOSAGE AND ADMINISTRATION and WARNINGS ). Facilities to treat shock should be available.
Adverse reactions
ADVERSE REACTIONS: To report SUSPECTED ADVERSE REACTIONS, contact Fresenius Kabi USA, LLC at 1-800-551-7176 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. The intravenous administration of protamine sulfate may cause a sudden fall in blood pressure and bradycardia. Other reactions include transitory flushing and feeling of warmth, dyspnea, nausea, vomiting and lassitude. Back pain has been reported in conscious patients undergoing such procedures as cardiac catheterization. Severe adverse reactions have been reported including: (1) Anaphylaxis that resulted in severe respiratory distress, circulation collapse and capillary leak (see PRECAUTIONS ). Fatal anaphylaxis has been reported in one patient with no prior history of allergies; (2) Anaphylactoid reactions with circulatory collapse, capillary leak, and noncardiogenic pulmonary edema; acute pulmonary hypertension. Complement activation by the heparin-protamine complexes, release of lysosomal enzymes from neutrophils, and prostaglandin and thomboxane generation have been associated with the development of anaphylactoid reactions. Severe and potentially irreversible circulatory collapse associated with myocardial failure and reduced cardiac output can also occur. The mechanism(s) of this reaction and the role played by concurrent factors are unclear. High-protein, noncardiogenic pulmonary edema associated with the use of protamine has been reported in patients on cardiopulmonary bypass who are undergoing cardiovascular surgery. The etiologic role of protamine in the pathogenesis of this condition is uncertain, and multiple factors have been present in most cases. The condition has been reported in association with administration of certain blood products, other drugs, cardiopulmonary bypass alone, and other etiologic factors. It is difficult to treat, and it can be life-threatening. Because fatal anaphylactic and anaphylactoid reactions have been reported after the administration of protamine sulfate, the drug should be given only when resuscitation techniques and treatment of anaphylactic and anaphylactoid shock are readily available.

Label text is reproduced as-is from the FDA-approved label. We do not paraphrase, summarize, or omit. Content above is for informational purposes only and is not medical advice. Always consult your prescribing clinician or pharmacist before making decisions about your medication.

Conditions we've indexed resources for

Click a condition to see copay cards, grants, and PA rules specific to it. For the full list of FDA-approved indications, see Prescribing information above.

Prior authorization & coverage

PayerPAStep therapyCopay tier

Medicare Part D

Medicare Part D

How this page is sourced

  • Drug identity verified against openFDA NDC Directory.
  • Label text (when shown) originates from NLM DailyMed.
  • Copay and assistance URLs verified periodically; if you hit a broken link, tell us.