Poisoning by, adverse effect of and underdosing of agents primarily affecting the gastrointestinal system

• birth trauma (P10-P15)
• obstetric trauma (O70-O71)

code to identify any retained foreign body, if applicable (Z18.-)

• Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
• The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.

• 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

toxic reaction to local anesthesia in pregnancy (O29.3-)

• abuse and dependence of psychoactive substances (F10-F19)
• abuse of non-dependence-producing substances (F55.-)
• immunodeficiency due to drugs (D84.821)
• drug reaction and poisoning affecting newborn (P00-P96)
• pathological drug intoxication (inebriation) (F10-F19)

• , for adverse effects, the nature of the adverse effect, such as:
• adverse effect NOS (T88.7)
• aspirin gastritis (K29.-)
• blood disorders (D56-D76)
• contact dermatitis (L23-L25)
• dermatitis due to substances taken internally (L27.-)
• nephropathy (N14.0-N14.2)

• code(s) to specify:
• manifestations of poisoning
• underdosing or failure in dosage during medical and surgical care (Y63.6, Y63.8-Y63.9)
• underdosing of medication regimen (Z91.12-, Z91.13-)

The drug giving rise to the adverse effect should be identified by use of codes from categories T36-T50 with fifth or sixth character 5.