Adverse effect of multiple unsp drug/meds/biol subst, init

This code signifies an unintended and undesirable reaction to the combined effect of several medications, biological substances, or other medicaments, where the specific substances involved are not identified. It indicates that the patient is experiencing the initial phase of care for this adverse event.

Apply this code when a patient presents with symptoms clearly linked to an adverse reaction from multiple, unidentifiable drugs or substances. This is appropriate for initial evaluations and treatments of such an event, before the specific agents causing the reaction have been determined.

• Ensure documentation explicitly states an adverse effect from "multiple unspecified" substances.
• Only use the "A" seventh character for the initial encounter for this condition.
• Do not use this code if the specific drugs or substances involved are known; instead, code to the specific drug class and adverse effect.