2026 ICD-10-CM Diagnosis Code T40.8X1SPoisoning by lysergide [LSD], accidental (unintentional), sequela
T40.8X1S is a billable ICD-10-CM diagnosis code for poisoning by lysergide [LSD], accidental (unintentional), sequela. The 7th character S marks it as a sequela code, which reports a problem that remains after the original condition has resolved. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 922 through 923. The code is exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Mental and substance use disorders; sequela; and Poisoning/toxic effect/adverse effects/underdosing, sequela.
Code Identity
Code Classification
Present on Admission (POA)Billing
T40.8X1S is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Accidental ergot alkaloid overdose
- Accidental ergot alkaloid poisoning
- Accidental overdose by lysergic acid diethylamide
- Accidental poisoning by hallucinogens
- Accidental poisoning by lysergic acid
- Adverse reaction to hallucinogen
- Adverse reaction to lysergide
- Ergoline drug adverse reaction
- Ergot alkaloid adverse reaction
- Overdose of lysergic acid diethylamide
- Poisoning by lysergide
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.
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.
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 T40.8X1S to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T40.8X1SOverview
Is T40.8X1S (Poisoning by lysergide [LSD], accidental (unintentional)) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report poisoning by lysergide [LSD], accidental (unintentional), sequela on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character S in T40.8X1S mean?
The final character S makes this a sequela code: it reports a lingering problem that remains after the poisoning by lysergide [LSD], accidental (unintentional) itself has resolved, not the original event.
What MS-DRG does T40.8X1S group to?
When poisoning by lysergide [LSD], accidental (unintentional), sequela is the principal diagnosis on an inpatient stay, it groups to MS-DRG 922, 923, with relative weights from 1.0177 to 1.7494 depending on complications. Higher weights mean higher Medicare reimbursement.
Is T40.8X1S exempt from POA reporting?
Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for poisoning by lysergide [LSD], accidental (unintentional), sequela on inpatient claims.
What is the ICD-9 equivalent of T40.8X1S?
Under the General Equivalence Mappings, poisoning by lysergide [LSD], accidental (unintentional), sequela converts to ICD-9-CM 909.0 (late eff drug poisoning) and E929.2 (late eff acc poisoning). 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.
