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Lok Pak

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Lok Pak


Heparin Lock Flush Solution, USP is indicated only to maintain potency of an intravenous injection device. It may be used following initial placement of the device in the vein, after each injection of a medication or after withdrawal of blood for laboratory analysis.

The solution is not to be used for anticoagulation therapy.


Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Slight discoloration does not alter potency. See PRECAUTIONS.

Heparin Lock Flush Solution, USP 10 or 100 USP Units/mL, is injected as a single dose into an intravenous injection device using a volume of solution equivalent to that of the indwelling venipuncture device.

A single dose should be injected following venipuncture when the indwelling device is not to be used immediately. After each use of the indwelling venipuncture device for injection or infusion of medication, or withdrawal of blood samples, another dose should be injected to restore the effectiveness of the heparin lock. The amount of heparin solution is sufficient to prevent clotting within the lumen of indwelling venipuncture devices (usually not holding more than 0.2 to 0.3 mL) for up to twenty-four hours.

When the indwelling device is used to administer a drug which is incompatible with heparin, the entire heparin lock set should be flushed with 0.9% Sodium Chloride Injection, USP before and after the medication is administered. Following the second flush, another dose of heparin solution should be injected to restore the effectiveness of the heparin lock.

When the indwelling device is used for repeated withdrawal of blood samples for laboratory analyses and the presence of heparin or saline is likely to interfere with or alter results of the desired blood tests, the in situ heparin flush solution should be cleared from the device by aspirating and discarding 1 mL before the desired blood sample is drawn. See PRECAUTIONS.


Heparin Lock Flush Solution, USP is supplied in dosage forms:

List No.
Dosage Form
(USP Units/mL)
1151 Fliptop Vial
1152 Fliptop Vial

Heparin sodium injection: Injection: 1,000 U/mL, 2,000 U/mL, 2,500 U/mL, 5,000 U/mL, 7,500 U/mL, 10,000 U/mL, 20,000 U/mL.
Heparin sodium and sodium chloride: Injection: 200 U/100 mL-0.9%, 5,000 U/100 mL-0.45%, 10,000 U/100 mL-0.45%; Pack: 10U/mL-0.9%, 100 U/mL-0.9%.
Heparin sodium lock flush solution: Kit: 10 U/mL, 100 U/mL

Store at controlled room temperature 15° to 30° C (59° to 86° F).

Last reviewed on RxList: 1/10/2004
This monograph has been modified to include the generic and brand name in many instances.


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