DIAGNOSIS: Neonatal single, full -term, live-born female
infant, transient diabetes mellitus.
PRINCIPLE XI. POISONING AND ADVERSE EFFECTS OF DRUGS AND E CODES
1. ICD-9-CM provides codes to differentiate betwe en poisoning and an adverse
reaction to a correct substance properly prescribed and administered correctly. (See
principle XIV for poisoning.)
2. The World Health Organization has proposed a definition of an adverse drug
reaction as any response to a drug "which is noxious and unintended and which occurs
at doses used in man for prophylaxis, diagnosis, or therapy".
3. Terms frequently used in diagnostic statements to identify adverse drug reaction to
a correct substance properly administered are : accumulative effect, allergic reaction,
idiosyncratic reaction, hypersensitivity, paradoxical reaction, and side effects,
synergistic reaction and antagonistic drug interactions.
4. Categories E93-E949 provide means to identify the drug responsible for a n
adverse reaction to a substance correctly administered. These E Code subcategories
provide the same specificity in identifying the drug involved in causing the adverse
reaction as do categories 96 -979 in identifying the drug involved in poisoning. Not e
that codes 96-979 cannot be used in combination with codes E93-E949. One
identifies a substance causing poison, and the other identifies a substance causing an
adverse reaction in therapeutic use.
5. The adverse reaction to a correct substance prop erly administered is classified to
the manifestation or the nature of the adverse reaction, such as gastritis, lymphadenitis,
urticaria, psychosis, etc.
6. Two codes are required to code an adverse reaction to a correct substance properly
administered. First code the adverse reaction using a code from 1-799 categories;
second, code the drug or substance which caused it, using an E code from the
Therapeutic column of the Table of Drugs and Chemicals. If the reaction is unknown,
use code 995.2 and the E code.
7. Codes E93-E949 can never be used as a solo code. The adverse reaction code is
always sequenced first. The E code can never be the principal diagnosis.
8. Code 995.2 will be used for unspecified nature of allergic or idiosyncratic reactions
to a correct substance properly administered (drug allergy, NOS). It is provided for
those cases in which a code from 1-799 cannot be assigned because the nature of
the reaction is not known/stated. In these cases 995.2 is sequenced first, and the E
code is an additional code.