T40.991Header code — not billable

Poisoning by other psychodysleptics [hallucinogens], accidental (unintentional)

Short description: Poisoning by oth psychodyslept, accidental (unintentional)

Chapter
19. Injury, poisoning and certain other consequences of external causes
Category
T40
Effective date
October 1, 2026

Related codes in category T40

T40Narcotics and psychodyslepticsT40.0Poisoning by, adverse effect of and underdosing of opiumT40.0XPoisoning by, adverse effect of and underdosing of opiumT40.0X1Poisoning by opium, accidental (unintentional)T40.0X1APoisoning by opium, accidental (unintentional), init encntrYesT40.0X1DPoisoning by opium, accidental (unintentional), subs encntrYesT40.0X1SPoisoning by opium, accidental (unintentional), sequelaYesT40.0X2Poisoning by opium, intentional self-harmT40.0X2APoisoning by opium, intentional self-harm, initial encounterYesT40.0X2DPoisoning by opium, intentional self-harm, subs encntrYesT40.0X2SPoisoning by opium, intentional self-harm, sequelaYesT40.0X3Poisoning by opium, assault

Frequently asked questions

What is ICD-10 code T40.991?

T40.991 is an ICD-10-CM diagnosis code for Poisoning by other psychodysleptics [hallucinogens], accidental (unintentional).

Is T40.991 a billable code?

No. T40.991 is a category/header code, not billable on its own — use one of its more specific child codes instead.

What ICD-10-CM chapter is T40.991 in?

T40.991 falls under Chapter 19: Injury, poisoning and certain other consequences of external causes.

When did T40.991 become effective?

T40.991 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.

What other codes are related to T40.991?

T40.991 belongs to category T40, which includes 12 other codes — see the related codes list on this page.

ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.