T42.8: Poisoning by, adverse effect of and underdosing of antiparkinsonism drugs and other central muscle-tone depressants
T42.8 is a non-billable header ICD-10-CM code for poisoning by, adverse effect of and underdosing of antiparkinsonism drugs and other central muscle-tone depressants. It cannot be billed on its own: choose one of the more specific child codes below. This code also requires a 7th character before it is complete.
This code requires a 7th character
The appropriate 7th character is to be added to each code from category T42
- A
- initial encounter
- D
- subsequent encounter
- S
- sequela
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Poisoning by, adverse effect of and underdosing of amantadine
Excludes2 inherited from the categories above T42.8
Not part of this code, but both may be coded when both are present.
Other codes that can never be billed with T42.8
Their own Excludes1 notes name this code, so the conflict is not listed above.
- T37.5Poisoning by, adverse effect of and underdosing of antiviral drugs
Risk adjustment
No CMS-HCC V28 category: this code does not change a RAF score.
Code history
Unchanged in every release from FY2024 to FY2027.
Code to one of these instead T42.8
1 child code. Green means billable.
Other codes under T42
- T42.0Poisoning by, adverse effect of and underdosing of hydantoin derivatives
- T42.1Poisoning by, adverse effect of and underdosing of iminostilbenes
- T42.2Poisoning by, adverse effect of and underdosing of succinimides and oxazolidinediones
- T42.3Poisoning by, adverse effect of and underdosing of barbiturates
- T42.4Poisoning by, adverse effect of and underdosing of benzodiazepines
- T42.5Poisoning by, adverse effect of and underdosing of mixed antiepileptics
- T42.6Poisoning by, adverse effect of and underdosing of other antiepileptic and sedative-hypnotic drugs
- T42.7Poisoning by, adverse effect of and underdosing of unspecified antiepileptic and sedative-hypnotic drugs