2026 ICD-10-CM Diagnosis Code T40.8X3APoisoning by lysergide [LSD], assault, initial encounter

ICD-10-CM CodesS00–T88T36-T50T40

ICD-10-CM T40.8X3A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

T40.8X3A is a billable ICD-10-CM diagnosis code for poisoning by lysergide [LSD], assault, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 917 through 918. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under External cause codes: intent of injury, assault; External cause codes: poisoning by drug; and Hallucinogen-related disorders.

Code Identity

ICD-10-CM Code
T40.8X3A
Billable Status
Yes — Valid for Submission
Code Describes
Poisoning by lysergide [LSD], assault, initial encounter
Short Description
Poisoning by lysergide [LSD], assault, initial encounter
Same as the full description in the CMS dataset.
Parent Code
Poisoning by lysergide [LSD], assault

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionT36-T50Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances
CategoryT40Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens]
This CodeT40.8X3APoisoning by lysergide [LSD], assault, initial encounter

Coding GuidelinesGuidance

When coding a poisoning or reaction to the improper use of a medication (e.g., overdose, wrong substance given or taken in error, wrong route of administration), first assign the appropriate code from categories T36-T50. The poisoning codes have an associated intent as their 5th or 6th character (accidental, intentional self-harm, assault and undetermined). If the intent of the poisoning is unknown or unspecified, code the intent as accidental intent. The undetermined intent is only for use if the documentation in the record specifies that the intent cannot be determined. Use additional code(s) for all manifestations of poisonings.

The appropriate 7th character is to be added to each code from block Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens] (T40). Use the following options for the applicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR EXT022
External cause codes: intent of injury, assault
Default principal diagnosis: inpatient No · outpatient No
CCSR EXT014
External cause codes: poisoning by drug
Default principal diagnosis: inpatient No · outpatient No
CCSR MBD022
Hallucinogen-related disorders
Default principal diagnosis: inpatient No · outpatient No
CCSR INJ022
Poisoning by drugs, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Lysergic Acid Diethylamide

    semisynthetic derivative of ergot (claviceps purpurea). it has complex effects on serotonergic systems including antagonism at some peripheral serotonin receptors, both agonist and antagonist actions at central nervous system serotonin receptors, and possibly effects on serotonin turnover. it is a potent hallucinogen, but the mechanisms of that effect are not well understood.

Table of Drugs and ChemicalsClinical

Substances in the Table of Drugs and Chemicals that reference this code family. Always confirm in the Tabular List before coding.

SubstanceAccidentalSelf-harmAssaultUndeter­minedAdverse
Effect
Under­dosing
D-lysergic acid diethylamideT40.8X1T40.8X2T40.8X3T40.8X4
LSDT40.8X1T40.8X2T40.8X3T40.8X4
Lysergic acid diethylamideT40.8X1T40.8X2T40.8X3T40.8X4
LysergideT40.8X1T40.8X2T40.8X3T40.8X4

Patient EducationClinical

Club Drugs

Club drugs are a group of psychoactive drugs. They act on the central nervous system and can cause changes in mood, awareness, and behavior. These drugs are most often used by young adults at bars, concerts, nightclubs, and parties.

The full article covers:

  • What are club drugs?
  • What are the different types of club drugs?
  • What are date rape drugs?
  • Are there steps I can take to protect myself from date rape drugs?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert T40.8X3A to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
969.6 Poisoning-hallucinogens
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.
ICD-9-CM
E962.0 Assault-pois w medic agt
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About T40.8X3AOverview

Is T40.8X3A (Poisoning by lysergide [LSD], assault) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report poisoning by lysergide [LSD], assault, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in T40.8X3A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for poisoning by lysergide [LSD], assault, such as an emergency visit or first evaluation.

What MS-DRG does T40.8X3A group to?

When poisoning by lysergide [LSD], assault, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 917, 918, with relative weights from 0.8571 to 1.5684 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of T40.8X3A?

Under the General Equivalence Mappings, poisoning by lysergide [LSD], assault, initial encounter converts to ICD-9-CM 969.6 (poisoning-hallucinogens) and E962.0 (assault-pois w medic agt). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.