T75.830UpcomingCategory · further specificity required

Gulf war illness

Chapters 19 · Inherited instructions

Use additional code

code to identify any retained foreign body, if applicable (Z18.-)

T75.83 · Inherited instructions

Use additional code

code to identify associated manifestations

T66-T78 · Inherited instructions

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-)

T75 · Inherited instructions

Excludes 1

adverse effects NEC (T78.-)

A — initial encounter

D — subsequent encounter

S — sequela

Excludes 2 · 3

Chapters 19 · Injury, poisoning and certain other consequences of external causes (S00-T88)

Excludes 2

birth trauma (P10-P15)
obstetric trauma (O70-O71)

T75 · Other and unspecified effects of other external causes

Excludes 2

burns (electric) (T20-T31)

More specific codes

T75.830AGulf war illness, initial encounter T75.830DGulf war illness, subsequent encounter T75.830SGulf war illness, sequela

Claims & coverage

When ICD-10-CM is required

For US diagnosis claims covered by HIPAA, ICD-10-CM is required from October 1, 2015.

Use the service date for outpatient/professional claims and the discharge date for hospital inpatient claims. Earlier encounters use ICD-9-CM; each individual code must also be valid for the applicable date.

Official coding guidelines → · CMS ↗

First observed · 2025-10-01

Code history

Latest recorded change · FY2026 · April

ChangedUnchanged

FY2026 · April

Effective from 2026-04-01

Inherited rules changed

Gulf war illness

Category — select a more specific code

CDC/NCHS · FY2026 · April

All editions (3)

All editions	Effective from	Code history
FY2026	2025-10-01	Added
FY2026 · April	2026-04-01	Inherited rules changed
FY2027	2026-10-01	No tabular change

Code-level instructions

Inclusion terms

Gulf war syndrome

Inherited instructions

Chapters 19 · Injury, poisoning and certain other consequences of external causes (S00-T88)

Excludes 2

birth trauma (P10-P15)
obstetric trauma (O70-O71)

Use additional code

code to identify any retained foreign body, if applicable (Z18.-)

Note

Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.

T75.83 · Effects of war theater

Use additional code

code to identify associated manifestations

T66-T78 · Other and unspecified effects of external causes (T66-T78)

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-)

T75 · Other and unspecified effects of other external causes

Excludes 1

adverse effects NEC (T78.-)

Excludes 2

burns (electric) (T20-T31)

Seventh character

The appropriate 7th character is to be added to each code from category T75

A — initial encounter

D — subsequent encounter

S — sequela

More specific codes

T75.830AGulf war illness, initial encounterBillable / specific T75.830DGulf war illness, subsequent encounterBillable / specific T75.830SGulf war illness, sequelaBillable / specific

Official index references (2)

Illness (1)

Illness › Gulf warDisease index

Syndrome (1)

Syndrome › Gulf warDisease index

Related codes

Other entries in the same category; these are not automatic substitutes.

Code	Description	Category · further specificity required
T75.838	Effects of other war theater	Category · further specificity required

Official titles and instructions are preserved in their source language. Official sources ↗

T75.830UpcomingCategory · further specificity required

Gulf war illness

Chapters 19 · Inherited instructions

Use additional code

code to identify any retained foreign body, if applicable (Z18.-)

T75.83 · Inherited instructions

Use additional code

code to identify associated manifestations

T66-T78 · Inherited instructions

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-)

T75 · Inherited instructions

Excludes 1

adverse effects NEC (T78.-)

A — initial encounter

D — subsequent encounter

S — sequela

Excludes 2 · 3

Chapters 19 · Injury, poisoning and certain other consequences of external causes (S00-T88)

Excludes 2

birth trauma (P10-P15)
obstetric trauma (O70-O71)

T75 · Other and unspecified effects of other external causes

Excludes 2

burns (electric) (T20-T31)

More specific codes

T75.830AGulf war illness, initial encounter T75.830DGulf war illness, subsequent encounter T75.830SGulf war illness, sequela

Claims & coverage

When ICD-10-CM is required

For US diagnosis claims covered by HIPAA, ICD-10-CM is required from October 1, 2015.

Official coding guidelines → · CMS ↗

First observed · 2025-10-01

Code history

Latest recorded change · FY2026 · April

ChangedUnchanged

FY2026 · April

Effective from 2026-04-01

Inherited rules changed

Gulf war illness

Category — select a more specific code

CDC/NCHS · FY2026 · April

All editions (3)

All editions	Effective from	Code history
FY2026	2025-10-01	Added
FY2026 · April	2026-04-01	Inherited rules changed
FY2027	2026-10-01	No tabular change

Code-level instructions

Inclusion terms

Gulf war syndrome

Inherited instructions

Chapters 19 · Injury, poisoning and certain other consequences of external causes (S00-T88)

Excludes 2

birth trauma (P10-P15)
obstetric trauma (O70-O71)

Use additional code

code to identify any retained foreign body, if applicable (Z18.-)

Note

Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.

T75.83 · Effects of war theater

Use additional code

code to identify associated manifestations

T66-T78 · Other and unspecified effects of external causes (T66-T78)

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-)

T75 · Other and unspecified effects of other external causes

Excludes 1

adverse effects NEC (T78.-)

Excludes 2

burns (electric) (T20-T31)

Seventh character

The appropriate 7th character is to be added to each code from category T75

A — initial encounter

D — subsequent encounter

S — sequela

More specific codes

T75.830AGulf war illness, initial encounterBillable / specific T75.830DGulf war illness, subsequent encounterBillable / specific T75.830SGulf war illness, sequelaBillable / specific

Official index references (2)

Illness (1)

Illness › Gulf warDisease index

Syndrome (1)

Syndrome › Gulf warDisease index

Related codes

Other entries in the same category; these are not automatic substitutes.

Code	Description	Category · further specificity required
T75.838	Effects of other war theater	Category · further specificity required

Official titles and instructions are preserved in their source language. Official sources ↗