What Is the Table of Drugs & Chemicals?
Medical coding the Table of Drugs & Chemicals is an alphabetical list of substances—including prescription medications, over-the-counter drugs, alcohols, gases, industrial chemicals, and other agents—that can cause toxic or adverse effects.
For each substance, the table provides a set of possible categories and codes based on the circumstances of exposure or use.
ICD10Data Table of Drugs ICD10Data: Table Of Drugs
Steps to Use the Table
Identify the Substance
- Review the provider documentation to determine the exact drug, chemical, or substance involved.
- If the documentation is vague (e.g., “pain medication”), query the provider for clarification, since specificity is required.
Go to the Table of Drugs & Chemicals in the Alphabetic Index
- Locate the substance in alphabetical order.
- For example: Acetaminophen, Ibuprofen, Carbon Monoxide, or Bleach.
Choose the Correct Column
Each substance has rows with six columns that correspond to the nature of the encounter:
1. Poisoning, Accidental (Unintentional) – Incorrect substance taken or wrong dose by mistake.
2. Poisoning, Intentional Self-Harm – Substance taken deliberately with the intent to harm oneself.
3. Poisoning, Assault – Substance administered by another person with the intent to harm.
4. Poisoning, Undetermined – When it’s unclear whether the poisoning was accidental, intentional, or assault.
5. Adverse Effect – A reaction to a substance taken correctly (e.g., prescribed dosage, but resulted in a side effect.
6. Underdosing – When a patient takes less of a medication than prescribed,it often leads to worsening of the condition.
Verify the Code in the Tabular List
- Always confirm the code in the Tabular List to ensure it matches documentation, includes the correct 7th character (if needed), and reflects any additional instructional notes.
- The Table provides suggested categories, but the final code selection comes from the Tabular List.
Assign Additional Codes
- If coding for poisoning, you may need to add codes for manifestations (e.g., seizures, coma).
- For adverse effects, assign the code for the manifestation first, followed by the drug adverse effect code.
- For underdosing, add a code to explain noncompliance or the reason for underdosing (e.g., financial hardship, patient refusal).
Example Scenarios
- Case 1: Accidental overdose of Ibuprofen
- Locate “Ibuprofen” in the Table → Poisoning, Accidental column → category T39.311A (Poisoning by ibuprofen, accidental, initial encounter).
- Verify in Tabular List.
- Case 2: Allergic reaction after correct penicillin use
- Locate “Penicillin” → Adverse Effect column → category T36.0X5A.
- Code the allergic reaction (e.g., urticaria) first, then add the adverse effect code.
- Case 3: Patient intentionally takes too much acetaminophen
- Locate “Acetaminophen” → Poisoning, Intentional Self-Harm column → T39.1X2A.
- Confirm in Tabular List.
Key Tips for Coders
- Do not assign codes directly from the Table—always verify in the Tabular List.
- Pay attention to 7th characters: “A” (initial), “D” (subsequent), or “S” (sequela).
- Be precise—look up the specific drug/chemical, not just the drug class, when possible.
- Use additional external cause codes (e.g., place of occurrence, activity) if required by guidelines.
The Table of Drugs & Chemicals is your starting point for coding toxic effects, poisonings, adverse effects, and underdosing. Proper navigation—substance, column, verification in the Tabular List, and sequencing—ensures accurate ICD-10-CM reporting and supports quality healthcare data.
ICD-10 Steps Medical Coding Steps For ICD-10-CM
Poisoning vs Adverse Effect vs Underdosing
| Situation | Definition | Sequencing |
| Poisoning | Wrong drug, wrong dose, wrong route, wrong patient, overdose, or a prescription drug taken with alcohol or a non-prescribed drug | Poisoning code (T36 to T65, columns 1 to 4) first, then the manifestations |
| Adverse effect | A reaction to a drug that was correctly prescribed and properly taken | The manifestation first (for example, rash or nausea), then the adverse effect code (5th or 6th character 5) |
| Underdosing | Taking less of a medication than prescribed or instructed | The relapse or exacerbation of the condition first, then the underdosing code (character 6), plus a noncompliance Z91.1- code when documented |
These rules come from ICD-10-CM Official Guidelines Section I.C.19.e.
The Table’s Six Columns
For each substance, the table lists codes for Poisoning: Accidental (Unintentional), Poisoning: Intentional Self-harm, Poisoning: Assault, Poisoning: Undetermined, Adverse Effect, and Underdosing. If the intent of a poisoning is unknown or unspecified, code it as accidental. Use undetermined only when the documentation states that the intent cannot be determined.
Frequently Asked Questions About the Table of Drugs and Chemicals
Where is the Table of Drugs and Chemicals?
It is in the ICD-10-CM Alphabetic Index, after the Neoplasm Table and before the External Cause Index.
Do I code directly from the table?
No. Always verify the code in the Tabular List to confirm the seventh character and any instructional notes.
What seventh character is used for poisoning codes?
A for initial encounter, D for subsequent encounter, and S for sequela, the same as other injury codes.
Is an allergic reaction to a correctly taken drug a poisoning?
No. A reaction to a correctly prescribed and properly taken drug is an adverse effect, not a poisoning.