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Test ID THEO Theophylline, Serum

Specimen Required


Preferred: Serum gel

Acceptable: Red top

Submission Container/Tube: Plastic vial

Specimen Volume: 0.5 mL

Collection Instructions:

1. Serum gel tubes should be centrifuged within 2 hours of collection.

2. Red-top tubes should be centrifuged and the serum aliquoted into a plastic vial within 2 hours of collection.

Useful For

Assessing and adjusting theophylline dosage for optimal therapeutic level


Assessing theophylline toxicity

Method Name

Kinetic Interaction of Microparticles in a Solution (KIMS)

Reporting Name

Theophylline, S

Specimen Type


Specimen Minimum Volume

0.25 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 14 days
  Frozen  28 days
  Ambient  72 hours

Reference Values


Bronchodilation: 8.0-20.0 mcg/mL

Neonatal apnea (≤4 weeks old): 6.0-13.0 mcg/mL

Critical value: >20.0 mcg/mL

Day(s) Performed

Monday through Saturday

Report Available

Same day/1 to 2 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information


LOINC Code Information

Test ID Test Order Name Order LOINC Value
THEO Theophylline, S 4049-3


Result ID Test Result Name Result LOINC Value
8661 Theophylline, S 4049-3


If not ordering electronically, complete, print, and send a Therapeutics Test Request (T831) with the specimen.