Parenteral Manual

Heparin sodium

Disclaimer: Official controlled document is the CHEO online copy. It is the responsibility of user to ensure that any paper copy version is the same as the online version before use.

Alternate Name(s): 
Original Date: 
August 2005
Revised Date: 
September 2011
  • Prevention or treatment of thromboembolic disorders
  • To prevent coagulation as blood passes through an extracorporeal circuit in dialysis procedures and during arterial and cardiac surgery
  • To maintain patency of IV catheter (hep lock)
  • Does not possess fibrinolytic activity, therefore cannot lyse established thrombi
Reconstitution and Stability: 
  • Stable at room temperature
  • Solutions are colourless to slightly yellow.  Minor colour variations do not affect potency
  • Heparin is available in many strengths;  please read label carefully:
    1. IV loading/bolus doses - 1,000 units/mL
    2. IV infusion - 100 units/mL
    3. SC use only - 10,000 units/mL
    4. Hep Lock - 100 units/mL

- Solutions Compatible: dextrose up to D10W, 0.9% NaCl, dextrose-saline combinations, RS, RL

- Additives/Above Cassette Compatible: clindamycin, dopamine, fentanyl, hydromorphone, KCl

-Y-site Compatible: amino acids/dextrose, hydrocortisone sodium succinate, calcium gluconate, digoxin, diphenhydramine, epinephrine, fluconazole, furosemide, lidocaine, morphine, norepinephrine, SMOF lipid 20%

Incompatible: alteplase, amikacin, ciprofloxacin, codeine, diazepam, erythromycin, fat emulsion (Intralipid 20%), gentamicin, phenytoin, and tobramycin - Infusion sets containing heparin should be irrigated with normal saline before these drugs are added.


(For approved routes of administration by nursing personnel, refer to Policy for the Administration of Intravenous Medications.)


YES, deep SC (above iliac or abdominal fat layer)

Usual dilution: 10,000 units/mL

IV Direct YES
Usual dilution: 1,000 units/mL
Infusion time: 5 minutes
IV Intermittent Infusion YES
Usual dilution: 40-1,000 units/mL
Infusion time: 10-15 minutes
IV Continuous Infusion YES
Usual dilution: 100 units/mL

Click here to access SDC Drug Infusion Sheet


(For neonatal dosages, refer to Neonatal IV Drug Manual.)

- Anticoagulant:

  • IV Infusion:       
    - Loading dose: 75 units/kg/dose IV over 10 minutes
    - Initial Maintenance:  <1 year: 28 units/kg/hour
                                           >1 year: 20 units/kg/hour
  • Adjust dose to maintain aPTT of 60-85 seconds

- Thromboembolism prophylaxis:  5,000 units SC Q 8-12 hours

- Anticoagulant:

  • IV Intermittent: 10,000 units initially, then 50-70 units/kg Q 4-6 hours
  • IV Infusion:
    - Loading dose: 80 units/kg
    - Initial Maintenance: 18 units/kg/hour

- Individualize the maintenance dose based on monitoring of aPTT

Potential hazards of parenteral administration: 
  • Overdosage - hemorrhage; may require D/C heparin infusion (antidote:  protamine)
  • Hypersensitivity reactions: fever, urticaria, asthma, rhinitis, arthralgia, anaphylaxis
  • Heparin-induced thrombocytopenia; monitor platelets
  • Nausea, vomiting, elevated liver enzymes
  • Before initiation of treatment -review patient's total drug regimen to prevent concomitant use of low molecular weight heparin and unfractionated heparin
  • Obtain baseline CBC, PT, and aPTT before starting treatment 
  • Blood for aPTT should NOT be drawn on extremity where heparin drip is infusing; if indicated, a heparin-free IV could be started for subsequent blood sampling                         
  • Avoid IM route due to erratic absorption, pain and hematoma formation at the site of injection
  • For immediate anticoagulation, an intravenous bolus followed by a continuous IV infusion is given since there is a delay in absorption/onset via the SC route
  • Avoid arterial punctures and antiplatelet agents (ASA)
  • Heparin and warfarin are sometimes given in combination until warfarin therapy is stabilized (i.e. INR is therapeutic)

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