Whether hyperbaric therapy is covered comes down to two things: the condition, and the paperwork.
The coverage rule
Medicare's National Coverage Determination 20.29 lists the conditions Medicare will cover HBOT for — the FDA-recognized indications — and specifies the clinical criteria that must be met and documented. Most private insurers model their policies on it.
The codes
Two codes do most of the work: CPT 99183 covers the physician's attendance and supervision of each session, while HCPCS G0277 (or C1300 in hospital outpatient settings) covers the chamber time itself, billed per 30-minute interval.
Why claims get denied
Coverage denials usually reflect documentation gaps, not ineligibility. For a diabetic foot ulcer, for example, payers want to see the wound grade, evidence that 30 days of standard care failed, and ongoing physician oversight. Good clinics build that record from the first visit.
The honest caveat
Off-label uses — such as concussion recovery or wellness protocols — are not covered by Medicare or private insurance. Reputable clinics say so upfront and quote self-pay costs rather than implying coverage that will not materialize.
Educational content, not medical advice — see our medical disclaimer. Terms in dotted teal link to the glossary.