Heparin Sodium
Various generics
Anticoagulant
| C | 1 | No | Yes | No |
| Key |
- Injection:
- Porcine intestinal mucosa: 1000, 5000, 10,000, 20,000 U/mL (some products may be preservative free; multidosed vials contain benzyl alcohol)
- Lock flush solution (porcine based): 10, 100 U/mL (some products may be preservative free or contain benzyl alcohol)
- Injection for IV infusion (porcine based):
- D5W: 40 U/mL (500 mL), 50 U/mL (250, 500 mL), 100 U/mL (100, 250 mL); contains bisulfite
- NS (0.9% NaCl): 2 U/mL (500, 1000 mL)
- 0.45% NaCl: 50 U/mL (250, 500 mL), 100 U/mL (250 mL); contains EDTA
- 120 U = approximately 1 mg
Dosing
- Anticoagulation empiric dosage:
- Continuous IV infusion (initial doses for goal unfractionated heparin [UFH] anti-Xa level of 0.3–0.7 units/mL):
| Age | Loading Dose (IV)a | Initial IV infusion Rate (units/kg/hr) |
| Neonate and infant <1 yr | 75 U/kg IV | 28 |
| Child age 1–18 yr | 75 U/kg IV (max. dose: 8000 U) | 20 (max. initial rate: 1650 U/hr) |
| >18 yr | 70 U/kg IV (max. dose: 8000 U) | 18 (max. initial rate: 1650 U/hr) |
a Do not give loading dose for patients with stroke or significant bleeding risk and obtain aPPT 4 hr after loading dose.
- DVT or PE prophylaxis:
- Adult: 5000 U/dose SC Q8–12 hr until ambulatory
- Heparin flush (doses should be less than heparinizing dose):
- Younger child: Lower doses should be used to avoid systemic heparinization.
- Older child and adult:
- Peripheral IV: 1–2 mL of 10 U/mL solution Q4 hr
- Central lines: 2–3 mL of 100 U/mL solution Q24 hr
- TPN (central line) and arterial line: Add heparin to make final concentration of 0.5–1 U/mL.
Notes
- Contraindicated in active major bleeding, known or suspected HIT, and concurrent epidural therapy. Use with caution if platelets <50,000/mm3. Avoid IM injections and other medications affecting platelet function (e.g., NSAIDs and ASA). Toxicities include bleeding, allergy, alopecia, and thrombocytopenia. May increase serum aminotransferases (AST and ALT).
- Adjust dose with one of the following laboratory goals:
- Unfractionated heparin (UFH) anti-Xa level: 0.3–0.7 units/mL
- aPTT level (reagent specific to reflect anti-Xa level of 0.3–0.7 units/mL): 50–80 sec
- These laboratory measurements are best measured 4–6 hr after initiation or changes in infusion rate. Do not collect blood levels from the heparinized line or same extremity as site of heparin infusion. If unfractionated heparin anti-Xa or aPTT levels are not available, a ratio of aPPT 1.5–2.5 times control value has been used in the past. Unfractionated heparin anti-Xa level is NOT THE SAME as low-molecular-weight heparin anti-Xa (used for monitoring low-molecular-weight heparin products such as enoxaparin).
- Use with IV nitroglycerin may decrease the partial thromboplastin time (PTT) with subsequent rebound upon discontinuation of nitroglycerin. Antithrombin III (human) and NSAIDs may increase heparin's anticoagulant effects and bleeding risk.
- Use preservative-free heparin in neonates. Note: Heparin flush doses may alter aPTT in smaller patients; consider using more dilute heparin in these cases. Multiple strengths of heparin exist, and do not use the more concentrated injectable product as flushes.
- Use actual body weight when dosing obese patients. Due to recent regulatory changes to the manufacturing process, heparin products may exhibit decreased potency.
- Antidote: Protamine sulfate (1 mg per 100 U heparin in previous 4 hr). For low-molecular-weight heparin (LMWH), see Enoxaparin.
Citation
Hughes, Helen K., and Lauren K. Kahl, editors. "Heparin Sodium." Harriet Lane Handbook, 23rd ed., Elsevier, 2024. Harriet Lane, www.unboundmedicine.com/harrietlane/view/Harriet_Lane_Handbook/309331/2/Heparin_Sodium.
Heparin Sodium. In: Hughes HKH, Kahl LKL, eds. Harriet Lane Handbook. Elsevier; 2024. https://www.unboundmedicine.com/harrietlane/view/Harriet_Lane_Handbook/309331/2/Heparin_Sodium. Accessed August 15, 2026.
Heparin Sodium. (2024). In Hughes, H. K., & Kahl, L. K. (Eds.), Harriet Lane Handbook (23rd ed.). Elsevier. https://www.unboundmedicine.com/harrietlane/view/Harriet_Lane_Handbook/309331/2/Heparin_Sodium
Heparin Sodium [Internet]. In: Hughes HKH, Kahl LKL, eds. Harriet Lane Handbook. Elsevier; 2024. [cited 2026 August 15]. Available from: https://www.unboundmedicine.com/harrietlane/view/Harriet_Lane_Handbook/309331/2/Heparin_Sodium.
* Article titles in AMA citation format should be in sentence-case
TY - ELEC
T1 - Heparin Sodium
ID - 309331
ED - Hughes,Helen K,
ED - Kahl,Lauren K,
BT - Harriet Lane Handbook
UR - https://www.unboundmedicine.com/harrietlane/view/Harriet_Lane_Handbook/309331/2/Heparin_Sodium
PB - Elsevier
ET - 23
DB - Harriet Lane
DP - Unbound Medicine
ER -

Harriet Lane Handbook

