Coding Ahead
CasePilot
Medical Coding Assistant
Case2Code
Search and Code Lookup Tool
CareerCenter
Medical Coding Job Board
Log in Register free account

Need help choosing the right code?

Ask CasePilot about procedures, modifiers, bundling, and coding guidance.

Try CasePilot

Official Description

Breath hydrogen or methane test (eg, for detection of lactase deficiency, fructose intolerance, bacterial overgrowth, or oro-cecal gastrointestinal transit)

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The breath hydrogen or methane test, identified by CPT® Code 91065, is a diagnostic procedure utilized to assess various gastrointestinal tract disorders. This test is particularly effective in evaluating conditions such as lactose intolerance, which is characterized by a deficiency in the enzyme lactase, and fructose intolerance, where the body is unable to properly absorb fructose. Additionally, the test is instrumental in detecting bacterial overgrowth in the small intestine, a condition where bacteria that typically reside in the colon proliferate in the small bowel, leading to excessive gas production. Furthermore, the breath test can help identify motility disorders, including rapid or prolonged oro-cecal gastrointestinal transit, which can affect the digestion and absorption of sugars. In a healthy individual, sugars like lactose, fructose, and glucose are absorbed in the small intestine. However, in cases of lactase deficiency or other malabsorption conditions, these sugars are not fully absorbed and instead pass into the large intestine. There, they undergo fermentation, resulting in the production of hydrogen and methane gases. The presence of these gases can also indicate bacterial overgrowth, which may occur when the normal balance of gut bacteria is disrupted, allowing gas-producing bacteria to thrive in the small intestine. The breath hydrogen or methane test is performed by having the patient fast for at least 12 hours prior to the procedure. A baseline breath sample is collected to measure the initial levels of hydrogen and methane. Following this, the patient ingests a small amount of a test sugar, after which additional breath samples are taken at 15-minute intervals over a period of 3 to 5 hours. The analysis of these samples helps determine whether there is malabsorption of the test sugar, as indicated by elevated levels of hydrogen or methane in the breath after ingestion.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The breath hydrogen or methane test is indicated for the evaluation of several gastrointestinal conditions, including:

  • Lactase Deficiency - This condition, commonly known as lactose intolerance, occurs when the body lacks sufficient lactase enzyme to properly digest lactose, leading to gastrointestinal symptoms.
  • Fructose Intolerance - This condition arises when the body is unable to absorb fructose effectively, resulting in similar gastrointestinal disturbances.
  • Bacterial Overgrowth - This occurs when there is an abnormal increase in the number of bacteria in the small intestine, which can lead to excessive gas production and malabsorption issues.
  • Oro-Cecal Gastrointestinal Transit Disorders - These disorders involve abnormal motility of the gastrointestinal tract, which can either speed up or slow down the transit of food through the intestines, affecting digestion and absorption.

2. Procedure

The breath hydrogen or methane test involves several key procedural steps to ensure accurate results:

  • Preparation - Prior to the test, the patient must fast for at least 12 hours to ensure that the results are not influenced by recent food intake. This fasting period is crucial for obtaining baseline measurements of hydrogen and methane levels.
  • Baseline Measurement - The procedure begins with the collection of a baseline breath sample. The patient is instructed to blow into a balloon, which collects the air. A sample of this breath is then analyzed to determine the initial levels of hydrogen and methane present.
  • Ingestion of Test Sugar - After the baseline measurement, the patient ingests a small amount of a test sugar, which may include lactose, fructose, sucrose, sorbitol, or lactulose. This ingestion is critical for assessing the body’s ability to absorb these sugars.
  • Collection of Post-Ingestion Samples - Following the ingestion of the test sugar, additional breath samples are collected at 15-minute intervals for a duration of 3 to 5 hours. This time frame allows for the observation of any changes in hydrogen or methane levels that may indicate malabsorption.
  • Analysis - The collected breath samples are analyzed to measure the levels of hydrogen and methane. An increase in these gases after the ingestion of the test sugar suggests malabsorption, confirming the presence of conditions such as lactase deficiency or fructose intolerance.

3. Post-Procedure

After the completion of the breath hydrogen or methane test, patients may resume their normal activities and diet unless otherwise instructed by their healthcare provider. It is important to monitor for any gastrointestinal symptoms that may arise following the test. The results of the test will be reviewed by the healthcare provider, who will discuss the findings and any necessary follow-up actions or treatments based on the test outcomes. Patients should be informed that the test is non-invasive and generally well-tolerated, with minimal risk of complications.

Short Descr BREATH HYDROGEN/METHANE TEST
Medium Descr BREATH HYDROGEN/METHANE TEST
Long Descr Breath hydrogen or methane test (eg, for detection of lactase deficiency, fructose intolerance, bacterial overgrowth, or oro-cecal gastrointestinal transit)
Status Code Active Code
Global Days 000 - Endoscopic or Minor Procedure
PC/TC Indicator (26, TC) 1 - Diagnostic Tests for Radiology Services
Multiple Procedures (51) 0 - No payment adjustment rules for multiple procedures apply.
Bilateral Surgery (50) 0 - 150% payment adjustment for bilateral procedures does NOT apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 0 - Payment restriction for assistants at surgery applies to this procedure...
Co-Surgeons (62) 0 - Co-surgeons not permitted for this procedure.
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Procedure or Service, Not Discounted when Multiple
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T2D - Other tests - other
MUE 2
CCS Clinical Classification 97 - Other gastrointestinal diagnostic procedures
26 Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number.
TC Technical component; under certain circumstances, a charge may be made for the technical component alone; under those circumstances the technical component charge is identified by adding modifier 'tc' to the usual procedure number; technical component charges are institutional charges and not billed separately by physicians; however, portable x-ray suppliers only bill for technical component and should utilize modifier tc; the charge data from portable x-ray suppliers will then be used to build customary and prevailing profiles
76 Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
GY Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit
GA Waiver of liability statement issued as required by payer policy, individual case
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.
GC This service has been performed in part by a resident under the direction of a teaching physician
CR Catastrophe/disaster related
GZ Item or service expected to be denied as not reasonable and necessary
25 Significant, separately identifiable evaluation and management service by the same physician or other qualified health care professional on the same day of the procedure or other service: it may be necessary to indicate that on the day a procedure or service identified by a cpt code was performed, the patient's condition required a significant, separately identifiable e/m service above and beyond the other service provided or beyond the usual preoperative and postoperative care associated with the procedure that was performed. a significant, separately identifiable e/m service is defined or substantiated by documentation that satisfies the relevant criteria for the respective e/m service to be reported (see evaluation and management services guidelines for instructions on determining level of e/m service). the e/m service may be prompted by the symptom or condition for which the procedure and/or service was provided. as such, different diagnoses are not required for reporting of the e/m services on the same date. this circumstance may be reported by adding modifier 25 to the appropriate level of e/m service. note: this modifier is not used to report an e/m service that resulted in a decision to perform surgery. see modifier 57 for significant, separately identifiable non-e/m services, see modifier 59.
52 Reduced services: under certain circumstances a service or procedure is partially reduced or eliminated at the discretion of the physician or other qualified health care professional. under these circumstances the service provided can be identified by its usual procedure number and the addition of modifier 52, signifying that the service is reduced. this provides a means of reporting reduced services without disturbing the identification of the basic service. note: for hospital outpatient reporting of a previously scheduled procedure/service that is partially reduced or cancelled as a result of extenuating circumstances or those that threaten the well-being of the patient prior to or after administration of anesthesia, see modifiers 73 and 74 (see modifiers approved for asc hospital outpatient use).
53 Discontinued procedure: under certain circumstances, the physician or other qualified health care professional may elect to terminate a surgical or diagnostic procedure. due to extenuating circumstances or those that threaten the well being of the patient, it may be necessary to indicate that a surgical or diagnostic procedure was started but discontinued. this circumstance may be reported by adding modifier 53 to the code reported by the individual for the discontinued procedure. note: this modifier is not used to report the elective cancellation of a procedure prior to the patient's anesthesia induction and/or surgical preparation in the operating suite. for outpatient hospital/ambulatory surgery center (asc) reporting of a previously scheduled procedure/service that is partially reduced or cancelled as a result of extenuating circumstances or those that threaten the well being of the patient prior to or after administration of anesthesia, see modifiers 73 and 74 (see modifiers approved for asc hospital outpatient use).
58 Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78.
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.
79 Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.)
93 Synchronous telemedicine service rendered via telephone or other real-time interactive audio-only telecommunications system : synchronous telemedicine service is defined as a real-time interaction between a physician or other qualified health care professional and a patient who is located away at a distant site from the physician or other qualified health care professional. the totality of the communication of information exchanged between the physician or other qualified health care professional and the patient during the course of the synchronous telemedicine service must be of an amount and nature that is sufficient to meet the key components and/or requirements of the same service when rendered via a face-to-face interaction.
95 Synchronous telemedicine service rendered via a real-time interactive audio and video telecommunications system: synchronous telemedicine service is defined as a real-time interaction between a physician or other qualified health care professional and a patient who is located at a distant site from the physician or other qualified health care professional. the totality of the communication of information exchanged between the physician or other qualified health care professional and the patient during the course of the synchronous telemedicine service must be of an amount and nature that would be sufficient to meet the key components and/or requirements of the same service when rendered via a face-to-face interaction. modifier 95 may only be appended to the services listed in appendix p. appendix p is the list of cpt codes for services that are typically performed face-to-face, but may be rendered via a real-time (synchronous) interactive audio and video telecommunications system.
AQ Physician providing a service in an unlisted health professional shortage area (hpsa)
CC Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed)
FQ The service was furnished using audio-only communication technology
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
GX Notice of liability issued, voluntary under payer policy
Q0 Investigational clinical service provided in a clinical research study that is in an approved clinical research study
X2 Continuous/focused services: for reporting services by clinicians whose expertise is needed for the ongoing management of a chronic disease or a condition that needs to be managed and followed with no planned endpoint to the relationship; reporting clinician service examples include but are not limited to: a rheumatologist taking care of the patient's rheumatoid arthritis longitudinally but not providing general primary care services
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
Date
Action
Notes
2016-01-01 Note AMA Guidelines changed.
2014-01-01 Changed Description Changed
2006-01-01 Changed Code description changed.
2005-01-01 Changed Code description changed.
Pre-1990 Added Code added.
Code
Description
Code
Description
Code
Description
Code
Description
Code
Description
CasePilot

Get instant expert-level medical coding assistance.

Ask about:
CPT Codes Guidelines Modifiers Crosswalks NCCI Edits Compliance Medicare Coverage
Example: "What is CPT code 99213?" or "Guidelines for E/M services"