CPT code 94644: Continuous inhalation, first hour2026 Medicare rate & RVUs in Maryland
Report continuous aerosol medication treatment for acute airway obstruction for the initial hour, such as prolonged nebulized bronchodilator therapy.
Medicare pays $63.15–$73.53 for 94644 in the office in Maryland, from Rest of Maryland to Washington, DC area. Which amount applies depends on the service address.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
Your location
On this page 9 sections
What 94644 covers
94644 describes continuous aerosol medication treatment for acute airway obstruction during the first hour. A clinician may provide it when a patient needs prolonged nebulized medication, such as continuous bronchodilator treatment during an acute asthma exacerbation. In an office or clinic, a respiratory therapist or other qualified clinical staff member may administer the treatment under physician supervision.
Report 94644 for the initial hour of continuous treatment, not for a routine brief inhalation treatment. Document the indication, medication, continuous delivery, and treatment duration so the record supports the service and the time billed. If treatment continues beyond the first hour, 94645 represents each additional hour. This service is billed as an incident-to service only when performed under physician supervision.
This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.
Where 94644 pays more and less in Maryland
The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.
3 payment localities
$63.15 to $73.53
| Payment locality | Office | Facility |
|---|---|---|
| Baltimore area, MD | $67.13 | Unavailable |
| Rest of Maryland | $63.15 | Unavailable |
| Washington, DC area | $73.53 | Unavailable |
How the 94644 rate is calculated
Each of 94644’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.
How the rate is built · 94644
RVUs × geographic indexes × conversion factor
Work0.00
0.00 RVUs× 1.000 GPCI
Practice expense1.85
1.85 RVUs× 1.000 GPCI
Malpractice0.02
0.02 RVUs× 1.000 GPCI
Adjusted RVUs
1.8700
Conversion factor
$33.4009
Medicare rate
$62.46
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for 94644
The CMS indicators that decide how 94644 is paid alongside other services.
CMS payment indicators · 94644
Continuous inhalation, first hour
| Rule | CMS value | What it means |
|---|---|---|
| Global period | XXX | The global surgery concept doesn’t apply. |
| Multiple procedures | 0 | No multiple-procedure reduction. |
| Bilateral (modifier 50) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 0 | Not paid without supporting documentation. |
| Co-surgeons (62) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 5 | Incident-to service. |
94644 compared with similar codes
Compare codes · National
4 codes, side by side
How to choose
- 94640Inhalation treatmentAcute obstruction or sputum induction
- Choose 94644 for continuous aerosol treatment during the first hour. Use 94640 for inhalation treatment for acute airway obstruction when the service is not continuous first-hour therapy.
- 94645Continuous inhalationEach additional hour
- 94644 reports the initial hour of continuous treatment; 94645 reports each additional hour after that.
- 94664Inhaler trainingTechnique demonstration and evaluation
- 94664 is for demonstrating or evaluating patient use of an inhaler. It does not describe continuous aerosol medication administration.
94644 billing questions
How does 94644 differ from 94640?
94644 is for continuous aerosol treatment during the first hour. 94640 describes an inhalation treatment for acute airway obstruction that is not reported as continuous first-hour therapy.
When is 94645 reported with 94644?
Report 94644 for the first hour and 94645 for each additional hour when continuous treatment extends beyond that initial hour.
What documentation supports 94644?
Document the acute airway indication, medication administered, continuous delivery, and duration. The record should establish that the service was performed under physician supervision.
Can a routine inhaler lesson be reported as 94644?
No. Teaching or evaluating a patient's use of an inhaler is described by 94664; 94644 is for continuous aerosol medication treatment.
Who may provide this service for Medicare billing?
The service is billed as incident-to only when performed under physician supervision. Clinical staff such as a respiratory therapist may administer the treatment in that setting.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.
CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file lines behind this rate
Fee sheets · Coming soon
Put 94644 and the rest of your codes on one sheet
Your codes at your locality, with payer contracts beside Medicare.
Join the waitlist