T70.29XA ICD-10-CM Code: Other effects of high altitude, initial encounter
T70.29XA is the authoritative medical code for Other effects of high altitude, initial encounter. This classification is used in medical billing and clinical recording to specify the clinical criteria for other effects of high altitude, initial encounter (ICD-10-CM T70.29XA), ensuring healthcare documentation aligns with current federal coding standards.
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Inpatient Payment Groups (MS-DRG)
MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43.0 (FY2026), Appendix B.
- MS-DRG 922 — OTHER INJURY, POISONING AND TOXIC EFFECT DIAGNOSES WITH MCC (MDC 21)
- MS-DRG 923 — OTHER INJURY, POISONING AND TOXIC EFFECT DIAGNOSES WITHOUT MCC (MDC 21)
A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.
Code Set: Valid FY2026 and FY2027. FY2026 took effect October 1, 2025.
Official Registry Overview & Definition
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for T70.29XA in the official ICD-10-CM tabular list.
Inclusion Terms
Alternative terms the tabular list files under this code.
- Alpine sickness
- Anoxia due to high altitude
- Barotrauma NOS
- Hypobaropathy
- Mountain sickness
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- polycythemia due to high altitude (D75.1)
Code Also
Additional codes that may be required to fully describe the encounter.
- Code also, if applicable, place of occurrence, such as:
- highway rest stop (Y92.523)
- school (private) (public) (state) as the place of occurrence of the external cause (Y92.21-)
- service areas as the place of occurrence of the external cause (Y92.52-)
- single-family non-institutional (private) house as the place of occurrence of the external cause (Y92.01-)
- transport vehicle as the place of occurrence of the external cause (Y92.81-)
Frequently Asked Questions (FAQ) & Clinical Guidance
Does T70.29XA require a 7th character?
Yes. The appropriate 7th character is to be added to each code from category T70.
Can T70.29XA be reported alongside related conditions?
Per official ICD-10-CM Excludes2 instructions, T70.29XA and the following are not considered part of each other and may both be reported when both conditions are present: polycythemia due to high altitude (D75.1).
What conditions are included under T70.29XA?
Other effects of high altitude, initial encounter includes: Alpine sickness; Anoxia due to high altitude; Barotrauma NOS; Hypobaropathy; Mountain sickness.
Nearest Codes in This Family
Official ICD-10-CM classifications closest to T70.29XA in its code family, with their registry titles.
- T70.20 — Unspecified effects of high altitude
- T70.20XA — Unspecified effects of high altitude, initial encounter
- T70.20XD — Unspecified effects of high altitude, subsequent encounter
- T70.20XS — Unspecified effects of high altitude, sequela
- T70.29 — Other effects of high altitude
- T70.29XD — Other effects of high altitude, subsequent encounter
- T70.29XS — Other effects of high altitude, sequela
- T70.3 — Caisson disease [decompression sickness]
- T70.3XXA — Caisson disease [decompression sickness], initial encounter
- T70.3XXD — Caisson disease [decompression sickness], subsequent encounter