| ICD-10 Code | Description |
| T40.411A | Poisoning by fentanyl or fentanyl analogs, accidental (unintentional), initial encounter |
| T40.411D | Poisoning by fentanyl or fentanyl analogs, accidental (unintentional), subsequent encounter |
| T40.411S | Poisoning by fentanyl or fentanyl analogs, accidental (unintentional), sequela |
| T40.412A | Poisoning by fentanyl or fentanyl analogs, intentional self-harm, initial encounter |
| T40.412D | Poisoning by fentanyl or fentanyl analogs, intentional self-harm, subsequent encounter |
| T40.412S | Poisoning by fentanyl or fentanyl analogs, intentional self-harm, sequela |
| T40.413A | Poisoning by fentanyl or fentanyl analogs, assault, initial encounter |
| T40.413D | Poisoning by fentanyl or fentanyl analogs, assault, subsequent encounter |
| T40.413S | Poisoning by fentanyl or fentanyl analogs, assault, sequela |
| T40.414A | Poisoning by fentanyl or fentanyl analogs, undetermined, initial encounter |
| T40.414D | Poisoning by fentanyl or fentanyl analogs, undetermined, subsequent encounter |
| T40.414S | Poisoning by fentanyl or fentanyl analogs, undetermined, sequela |
| T40.415A | Adverse effect of fentanyl or fentanyl analogs, initial encounter |
| T40.415D | Adverse effect of fentanyl or fentanyl analogs, subsequent encounter |
| T40.415S | Adverse effect of fentanyl or fentanyl analogs, sequela |
| T40.416A | Underdosing of fentanyl or fentanyl analogs, initial encounter |
| T40.416D | Underdosing of fentanyl or fentanyl analogs, subsequent encounter |
| T40.416S | Underdosing of fentanyl or fentanyl analogs, sequela |
| T40.421A | Poisoning by tramadol, accidental (unintentional), initial encounter |
| T40.421D | Poisoning by tramadol, accidental (unintentional), subsequent encounter |
| T40.421S | Poisoning by tramadol, accidental (unintentional), sequela |
| T40.422A | Poisoning by tramadol, intentional self-harm, initial encounter |
| T40.422D | Poisoning by tramadol, intentional self-harm, subsequent encounter |
| T40.422S | Poisoning by tramadol, intentional self-harm, sequela |
| T40.423A | Poisoning by tramadol, assault, initial encounter |
| T40.423D | Poisoning by tramadol, assault, subsequent encounter |
| T40.423S | Poisoning by tramadol, assault, sequela |
| T40.424A | Poisoning by tramadol, undetermined, initial encounter |
| T40.424D | Poisoning by tramadol, undetermined, subsequent encounter |
| T40.424S | Poisoning by tramadol, undetermined, sequela |
| T40.425A | Adverse effect of tramadol, initial encounter |
| T40.425D | Adverse effect of tramadol, subsequent encounter |
| T40.425S | Adverse effect of tramadol, sequela |
| T40.426A | Underdosing of tramadol, initial encounter |
| T40.426D | Underdosing of tramadol, subsequent encounter |
| T40.426S | Underdosing of tramadol, sequela |
| T40.491A | Poisoning by other synthetic narcotics, accidental (unintentional), initial encounter |
| T40.491D | Poisoning by other synthetic narcotics, accidental (unintentional), subsequent encounter |
| T40.491S | Poisoning by other synthetic narcotics, accidental (unintentional), sequela |
| T40.492A | Poisoning by other synthetic narcotics, intentional self-harm, initial encounter |
| T40.492D | Poisoning by other synthetic narcotics, intentional self-harm, subsequent encounter |
| T40.492S | Poisoning by other synthetic narcotics, intentional self-harm, sequela |
| T40.493A | Poisoning by other synthetic narcotics, assault, initial encounter |
| T40.493D | Poisoning by other synthetic narcotics, assault, subsequent encounter |
| T40.493S | Poisoning by other synthetic narcotics, assault, sequela |
| T40.494A | Poisoning by other synthetic narcotics, undetermined, initial encounter |
| T40.494D | Poisoning by other synthetic narcotics, undetermined, subsequent encounter |
| T40.494S | Poisoning by other synthetic narcotics, undetermined, sequela |
| T40.495A | Adverse effect of other synthetic narcotics, initial encounter |
| T40.495D | Adverse effect of other synthetic narcotics, subsequent encounter |
| T40.495S | Adverse effect of other synthetic narcotics, sequela |
| T40.496A | Underdosing of other synthetic narcotics, initial encounter |
| T40.496D | Underdosing of other synthetic narcotics, subsequent encounter |
| T40.496S | Underdosing of other synthetic narcotics, sequela |
