T36-T50 — Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances
ICD-10-CM codes T36-T50 cover poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances, within injury, poisoning and certain other consequences of external causes. The block holds 4,574 codes across 15 categories, of which 3,186 are billable and 1,388 are header codes that cannot be submitted on a claim. 4,574 of them (100%) require a 7th character.
Excludes1 — never code together
These conditions cannot occur together. Billing both on the same encounter is a denial.
- toxic reaction to local anesthesia in pregnancy (O29.3-)
Excludes2 — not included here, but may coexist
The excluded condition is not part of this code, but a patient can have both. You may code both.
Code first
The underlying condition must be sequenced before this code.
Use additional code
Add a secondary code to capture the detail described below.
Includes
Conditions this code covers.
- adverse effect of correct substance properly administered
- poisoning by overdose of substance
- poisoning by wrong substance given or taken in error
- underdosing by (inadvertently) (deliberately) taking less substance than prescribed or instructed
Notes
Additional guidance from the ICD-10-CM tabular list.
The 7th character in T36-T50
A code in this block is not complete without its 7th character, and a missing one is a rejected claim rather than a denied one: the clearinghouse never passes it on. 4,574 of the 4,574 codes here take one.
- A
- initial encounter
- D
- subsequent encounter
- S
- sequela
Risk adjustment in T36-T50
0 codes in this block map to a CMS-HCC, which means the diagnosis carries a risk-adjustment payment when it is documented and coded. Under-coding here is money left on the table; over-coding here is what audits are for.
- HCC 155 Major Depression, Moderate or Severe, without Psychosis
- HCC 137 Drug Use Disorder, Moderate/Severe, or Drug Use with Non-Psychotic Complications
What else to watch in T36-T50
- 3,173 codes are named in Medicare coverage policies. An LCD or NCD lists them as supporting medical necessity, or explicitly as not supporting it. Which applies depends on the MAC for your state.
Categories in T36-T50
- T36Poisoning by, adverse effect of and underdosing of systemic antibiotics
- T37Poisoning by, adverse effect of and underdosing of other systemic anti-infectives and antiparasitics
- T38Poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified
- T39Poisoning by, adverse effect of and underdosing of nonopioid analgesics, antipyretics and antirheumatics
- T40Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens]
- T41Poisoning by, adverse effect of and underdosing of anesthetics and therapeutic gases
- T42Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs
- T43Poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified
- T44Poisoning by, adverse effect of and underdosing of drugs primarily affecting the autonomic nervous system
- T45Poisoning by, adverse effect of and underdosing of primarily systemic and hematological agents, not elsewhere classified
- T46Poisoning by, adverse effect of and underdosing of agents primarily affecting the cardiovascular system
- T47Poisoning by, adverse effect of and underdosing of agents primarily affecting the gastrointestinal system
- T48Poisoning by, adverse effect of and underdosing of agents primarily acting on smooth and skeletal muscles and the respiratory system
- T49Poisoning by, adverse effect of and underdosing of topical agents primarily affecting skin and mucous membrane and by ophthalmological, otorhinorlaryngological and dental drugs
- T50Poisoning by, adverse effect of and underdosing of diuretics and other and unspecified drugs, medicaments and biological substances