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THEOPHYLLINE, SERUM

Synonym(s):
Lab Section Category
View write-up
Specimen Required

​3 mL plain blood

For the peak level, draw blood 2h after administration of drug with rapid release properties, or 4h after administration of drug with sustained release properties.

For trough level, draw sample just before the next dose.

Method

​Immunoassay

Reference Interval / Value

​Therapeutic Range : From 0 day : 8 - 20 mg/L

Turnaround Time

​Mean = 4 hrs, Range: 3 – 5 hrs

Day(s) Test Set up

​Daily

Last Updated - 13 Jun 2025