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Official Description

Theophylline

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 80198 refers to a laboratory test specifically designed to measure the levels of theophylline in the blood. Theophylline is a medication that is commonly used in the management of respiratory conditions. It is known by various names, including Aminophylline, Uniphyl, and Elixophylline. This medication can be administered through oral or intravenous routes and functions primarily by relaxing the muscles in the lungs and chest. This relaxation helps to reduce the reactivity of these muscles to allergens and bronchospasm, which is particularly beneficial for patients suffering from conditions such as acute bronchitis, asthma, and emphysema. Additionally, theophylline may be utilized in neonatal care to address apnea in newborns. The process of obtaining a blood sample for this test involves a venipuncture, which is a separate reportable procedure. Once the blood sample is collected, the serum is analyzed using a technique known as reflectance spectrophotometry, which allows for accurate measurement of theophylline levels in the bloodstream.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The measurement of theophylline levels in the blood is indicated for several specific conditions and symptoms, particularly those related to respiratory health. The following are the primary indications for performing this test:

  • Acute Bronchitis - Theophylline is used to manage symptoms associated with acute bronchitis, helping to alleviate airway constriction.
  • Chronic Respiratory Conditions - This includes conditions such as asthma and emphysema, where theophylline can assist in improving airflow and reducing respiratory distress.
  • Apnea in Neonates - Theophylline may be administered to newborns to treat episodes of apnea, a condition where breathing temporarily stops.

2. Procedure

The procedure for measuring theophylline levels involves several key steps that ensure accurate results. The following outlines the procedural steps:

  • Step 1: Patient Preparation - Prior to the blood draw, the patient may need to be informed about the test and any necessary preparations, such as fasting or medication adjustments, although specific instructions are not detailed in the provided data.
  • Step 2: Venipuncture - A qualified healthcare professional performs a venipuncture to obtain a blood sample. This involves inserting a needle into a vein, typically in the arm, to collect the necessary volume of blood for testing. The venipuncture is a separately reportable procedure and must be documented accordingly.
  • Step 3: Serum Separation - After the blood sample is collected, it is processed to separate the serum from the cellular components. This step is crucial as the serum is required for the subsequent analysis.
  • Step 4: Reflectance Spectrophotometry - The serum is then subjected to testing using reflectance spectrophotometry, a method that measures the concentration of theophylline in the serum by analyzing the light reflected from the sample.

3. Post-Procedure

After the procedure, the patient may be monitored for any immediate reactions to the venipuncture, such as bleeding or discomfort at the site. There are no specific post-procedure care instructions provided in the data; however, it is generally advisable for patients to hydrate adequately and follow any additional instructions given by their healthcare provider. The results of the theophylline level test will be interpreted by the physician to guide further treatment decisions, particularly in managing the patient's respiratory condition.

Short Descr ASSAY OF THEOPHYLLINE
Medium Descr DRUG SCREEN QUANTITATIVE THEOPHYLLINE
Long Descr Theophylline
Status Code Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 9 - Not Applicable
Multiple Procedures (51) 9 - Concept does not apply.
Bilateral Surgery (50) 9 - Concept does not apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 9 - Concept does not apply.
Team Surgery (66) 9 - Concept does not apply.
Diagnostic Imaging Family 99 - Concept Does Not Apply
CLIA Waived (QW) No
APC Status Indicator Conditionally packaged laboratory tests
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1H - Lab tests - other (non-Medicare fee schedule)
MUE 2
CCS Clinical Classification 235 - Other Laboratory
90 Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.
Q4 Service for ordering/referring physician qualifies as a service exemption
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
77 Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
91 Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient.
GA Waiver of liability statement issued as required by payer policy, individual case
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
GW Service not related to the hospice patient's terminal condition
Date
Action
Notes
2013-01-01 Changed Medium description changed per AMA 2013 corrections document dated January 25, 2013.
1993-01-01 Added First appearance in code book in 1993.
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