Valproate (Epilim)

Clinical use

Recommended sampling time -trough levels (consistently)

Background

Valproate is used in the control of grand and petit mal epilepsy and as such requires therapeutic drug monitoring. The drug is completely absorbed reaching a peak in approximately 4 hours with 90% being protein bound. It affects and is affected by concomitant use of phenytoin. Although the mechanism is not fully understood it appears to increase gamma-aminobutyric acid (GABA) levels which have anticonvulsant properties.

Reference ranges

Therapeutic Range: 50 – 100 mg/L

Specimen requirements

Sample type:

• Serum and Plasma (Lithium Heparin)

Sample identification:

• Three patient identifiers from
  • NameDOBAddressNHS numberUnit Number
  should match on the specimen and request form. This check may be performed prior to centrifugation by the Central Sort department.

Turnaround time

2 hours

Analysing laboratory

• Biochemistry Lab, James Cook University Hospital, Marton Road, TS4 3BW
• Biochemistry Lab, Friarage Hospital, Northallerton, DL6 1JG