Skip to content
Dx

ICD-10-CM 2027

ICD-10 code for altitude sickness

T70.20

Unspecified effects of high altitude

Header — needs a more specific code

From the official ICD-10-CM alphabetic index entry “Sickness › altitude”. Page updated September 29, 2026.

About coding altitude sickness

The ICD-10-CM code for altitude sickness is T70.20 (Unspecified effects of high altitude).

Within T70.2, choose T70.20 (Unspecified effects of high altitude) only when documentation doesn't support a more specific option: other effects of high altitude (T70.29).

Codes in this range require a 7th character: A for initial encounter, D for subsequent encounter and S for sequela. Use placeholder "X" characters to fill any empty positions before the 7th character.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Common questions about altitude sickness ICD-10 codes

What is the ICD-10 code for altitude sickness?

T70.20 — Unspecified effects of high altitude (a header code; report a more specific subcode).

Is T70.20 billable?

No. T70.20 is a header code. Report one of its more specific subcodes instead.