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CEREBYX® (fosphenytoin sodium) How Supplied/Storage and Handling


16.1 How Supplied

CEREBYX Injection is a clear, colorless to pale yellow solution supplied as follows:

mg phenytoin sodium equivalents (PE) per vial Volume per vial (mL) Package Configuration NDC
500 mg PE/10 mL vial
10 mL per vial
Package contains 10 vials of NDC 0069-6001-10 NDC 0069-6001-21
100 mg PE/2 mL vial
2 mL per vial Package contains 25 vials of NDC 0069-6001-02 NDC 0069-6001-25

Both sizes of vials contain Tromethamine, USP (TRIS), Hydrochloric Acid, NF, or Sodium Hydroxide, NF, and Water for Injection, USP.

CEREBYX should always be prescribed in phenytoin sodium equivalents (PE) [see Dosage and Administration (2.1) and Warnings and Precautions (5.1)].

1.5 mg of fosphenytoin sodium is equivalent to 1 mg phenytoin sodium, and is referred to as 1 mg PE. The amount and concentration of fosphenytoin is always expressed in terms of mg of phenytoin sodium equivalents (PE). Fosphenytoin's weight is expressed as phenytoin sodium equivalents to avoid the need to perform molecular weight-based adjustments when substituting fosphenytoin for phenytoin or vice versa.

16.2 Storage and Handling

Store under refrigeration at 2°C to 8°C (36°F to 46°F). The product should not be stored at room temperature for more than 48 hours. Vials that develop particulate matter should not be used.

Injection vials are single-dose only. After opening, any unused product should be discarded.

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