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Heparin Antidote

  • Termination of the IV infusion generally will terminate the anticoagulant effect.

  • If immediate reversal is required protamine sulfate will result in neutralization of heparin. The dose of protamine is based on the amount of heparin administered in the previous 2 hours using Table 2.

Table 2-Protamine sulfate for immediate reversal

 Time since last heparin dose  Protamine dose/100 units heparin given
<30 minutes 1 mg
30-60 minutes 0.5-0.75 mg
60-120 minutes 0.375-0.5 mg
>120 minutes 0.25-0.375 mg


  • Maximum Protamine dose is 50 mg.

  • Protamine should be given IV over 10 minutes. Infusion rate should not exceed 5 mg/min. More rapid infusion may result in hypotension. Patients with hypersensitivity to fish and those who have received protamine-containing insulin or previous protamine therapy may be at risk of hypersensitivity reactions.

  • Obtain blood for an PTT and PT 15 minutes after the administration of protamine.

  • Excessive Protamine doses may worsen bleeding potential.


David, M., et al. Heparin and LMWH in Children. Thrombosis Interest Group of Canada. January 2007. Accessed 11/15/08.

Lexi-Drugs Online/Pediatric Lexi-Drugs Online, Enoxaparin,, Copyright © 1978-2008 Lexi-Comp, Inc, Hudson, OH 44236

Monagle P, Chan AKC, Goldenberg NA, Ichord RN, Journeycake JM, Nowak-Gottl U, Vesely SK. Antithrombotic therapy in neonates and children: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest 2012; 141: e737S –e801S.

Roach ES. Golomb MR. Adams R. Biller J. Daniels S. Deveber G. Ferriero D. Jones BV. Kirkham FJ. Scott RM. Smith ER. American Heart Association Stroke Council. Council on Cardiovascular Disease in the Young. Management of stroke in infants and children: a scientific statement from a Special Writing Group of the American Heart Association Stroke Council and the Council on Cardiovascular Disease in the Young. [Journal Article] Stroke. 39(9):2644-91, 2008 Sep.

These pathways do not establish a standard of care to be followed in every case. It is recognized that each case is different, and those individuals involved in providing health care are expected to use their judgment in determining what is in the best interests of the patient based on the circumstances existing at the time. It is impossible to anticipate all possible situations that may exist and to prepare a pathway for each. Accordingly, these pathways should guide care with the understanding that departures from them may be required at times.