Billable / Specific Code
ICD-10-CM T40.991 is the diagnosis code for Poisoning by other psychodysleptics [hallucinogens], accidental (unintentional). This code falls under the section "Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances" within Chapter 19 — Injury, poisoning and certain other consequences of external causes (S00-T88). It is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.
Understanding where T40.991 sits in the ICD-10-CM classification helps ensure proper coding:
Yes, T40.991 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
T40.991 is the ICD-10-CM diagnosis code for "Poisoning by other psychodysleptics [hallucinogens], accidental (unintentional)". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.
The parent code of T40.991 is T40.99 ("Poisoning by, adverse effect of and underdosing of other psychodysleptics [hallucinogens]"). T40.991 provides a more specific classification within this category.
T40.991 is located in Section T36-T50 — "Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances" within Chapter 19 of the ICD-10-CM Tabular List.
Use T40.991 when the patients documented diagnosis matches "Poisoning by other psychodysleptics [hallucinogens], accidental (unintentional)" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.
The ICD-10-CM code for Poisoning by other psychodysleptics [hallucinogens], accidental (unintentional) is T40.991.
Yes, T40.991 can be used as a primary diagnosis code since it is billable and specific.
T40.991 is in Chapter 19 of the ICD-10-CM Tabular List.
Yes, T40.991 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.