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Electrolyte/Discontinued

HEPARIN SODIUM 25,000 UNITS IN SODIUM CHLORIDE 0.45% IN PLASTIC CONTAINER

HEPARIN SODIUM 25,000 UNITS IN SODIUM CHLORIDE 0.45% IN PLASTIC CONTAINER

Clinical safety rating

safe

No significant drug interactions Can cause hypernatremia and fluid overload.


Mechanism of Action

Heparin binds to antithrombin III, accelerating its inhibition of thrombin (factor IIa) and factor Xa, leading to anticoagulation.

What the body does with it

MetabolismPrimarily metabolized by the liver via desulfation and depolymerization; partially cleared by the reticuloendothelial system.
ExcretionRenal: 40% (as unchanged drug and metabolites); hepatic/biliary: minimal (<5%); fecal: negligible.
Half-lifeTerminal elimination half-life: 1.5–2 hours (dose-dependent and saturable clearance); prolonged in hepatic/renal impairment and at higher doses.
Protein bindingVery high: ~95–98% (primarily to antithrombin III, also albumin and other proteins); binding is saturable.
Volume of DistributionVd: 0.05–0.1 L/kg; primarily confined to plasma volume (low distribution); minimal extravascular penetration.
BioavailabilitySubcutaneous: 30–35% (due to first-pass clearance and tissue binding); intravenous: 100%.
Onset of ActionIntravenous: immediate (within minutes); subcutaneous: 20–30 minutes; intramuscular: avoided due to hematoma risk.
Duration of ActionIntravenous: 2–6 hours (mean 4 hours); subcutaneous: 8–12 hours; clinical monitoring (aPTT) required for dose adjustment.
Molecular Weight15000

Classification & Brands

Dosing & administration

Continuous IV infusion: Initial bolus 80 units/kg, then 18 units/kg/hour; adjust based on aPTT. Typical infusion rate: 1000-2000 units/hour for adults.

Dosage formINJECTABLE
Renal impairmentNo specific GFR-based dose adjustment required; monitor aPTT closely in renal impairment due to increased bleeding risk.
Liver impairmentNo established Child-Pugh based guidelines; use with caution and monitor aPTT due to reduced antithrombin III and increased bleeding risk.
Pediatric useIV: Bolus 75-100 units/kg, then maintenance infusion 20-25 units/kg/hour; adjust to target aPTT.
Geriatric useLower initial doses recommended (e.g., bolus 50-60 units/kg, infusion 12-15 units/kg/hour) due to altered pharmacokinetics and increased bleeding risk; monitor aPTT closely.

Use during pregnancy

1st trimesterHeparin does not cross the placenta; no evidence of teratogenicity. Use if clinically indicated.
2nd trimesterNo increased risk of fetal harm; monitor for maternal bleeding.
3rd trimesterRisk of maternal hemorrhage; use with caution. Avoid near delivery due to risk of epidural hematoma.

Clinical note

No significant drug interactions Can cause hypernatremia and fluid overload.

FDA categoryAnimal
Placental transferHeparin does not cross the placenta due to high molecular weight and negative charge.
BreastfeedingHeparin is not excreted into breast milk due to high molecular weight and poor oral bioavailability; considered compatible with breastfeeding.
Lactation RatingSafe
Teratogenic RiskHeparin does not cross the placenta and has not been associated with teratogenicity in any trimester. No increased risk of fetal malformations. Prolonged use may be associated with maternal osteoporosis and hemorrhage, but fetal risks are minimal.
Fetal MonitoringMonitor maternal platelet count (risk of heparin-induced thrombocytopenia), signs of bleeding, anti-Xa levels if needed, and fetal growth and well-being with ultrasound if prolonged use. Assess for osteoporosis with long-term therapy.
Fertility EffectsNo known adverse effects on fertility. Heparin is used in assisted reproductive technology protocols without evidence of impairment.

Warnings & precautions

■ FDA Black Box Warning

Heparin-induced thrombocytopenia (HIT) can occur; monitor platelets closely. Risk of bleeding, especially in patients with uncontrolled hypertension or concomitant use of antiplatelet agents.

Side Effect Profile

Common Effectsfluid replacement
Serious Effects

Absolute Contraindications

Active major bleedingHistory of heparin-induced thrombocytopeniaKnown hypersensitivity to heparinSevere thrombocytopeniaInability to perform adequate coagulation monitoring

Clinical Precautions

PrecautionsMonitor for signs of bleeding; adjust dose based on aPTT. Discontinue if HIT is confirmed. Use with caution in renal impairment, hepatic disease, or history of gastrointestinal ulcers.
Food/DietaryNo specific food interactions with heparin. However, foods high in vitamin K (e.g., leafy greens) may theoretically affect coagulation but are not clinically significant with heparin therapy. Maintain a consistent diet if on concurrent warfarin.

Clinical Tips & Counseling

Clinical PearlsThis formulation contains sodium chloride 0.45% (half-normal saline) and heparin 25,000 units. It is commonly used for continuous IV infusion to maintain catheter patency or for anticoagulation. Verify the concentration before administration; a common error is confusing this with heparin flush solutions. Monitor aPTT closely when used for systemic anticoagulation; the half-normal saline may affect fluid balance in patients with renal impairment or heart failure. Use with caution in patients with heparin-induced thrombocytopenia (HIT).
Patient AdviceThis medication is an anticoagulant that helps prevent blood clots. · You will receive this medication through an intravenous (IV) line. · Report any signs of bleeding, such as unusual bruising, blood in urine or stool, or prolonged bleeding from cuts. · Avoid activities that may cause injury or bleeding while on this medication. · Inform your healthcare provider if you have a history of heparin-induced thrombocytopenia (HIT) or other bleeding disorders. · Do not take aspirin or other NSAIDs (e.g., ibuprofen) unless prescribed by your doctor. · You may need frequent blood tests to monitor your response to the medication.

HEPARIN SODIUM 25,000 UNITS IN SODIUM CHLORIDE 0.45% IN PLASTIC CONTAINER Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

ACETATED RINGER'S IN PLASTIC CONTAINERACYCLOVIR IN SODIUM CHLORIDE 0.9% PRESERVATIVE FREEAMIKACIN SULFATE IN SODIUM CHLORIDE 0.9% IN PLASTIC CONTAINERAMIKIN IN SODIUM CHLORIDE 0.9% IN PLASTIC CONTAINERAMINOPHYLLINE IN SODIUM CHLORIDE 0.45%

External sources

DailyMed (NIH) PubMed OpenFDA