Adverse effect of agents prim acting on the resp sys, init

This code signifies an unintended and harmful reaction experienced by a patient due to a therapeutic dose of a medication or substance primarily affecting the respiratory system, where the specific agent is not otherwise classified. This adverse effect occurs during the initial period of treatment or exposure.

Use this code when a patient presents with respiratory symptoms (e.g., bronchospasm, respiratory depression, pulmonary edema) that are determined to be an adverse effect of a prescribed or administered drug whose primary action is on the respiratory system, but a more specific agent code is unavailable. This applies to the first time the patient is seen for this particular adverse reaction.

• Always sequence the manifestation code(s) of the adverse effect first, followed by this code.
• Ensure the documentation clearly states an "adverse effect" and not poisoning, underdosing, or toxic effect.
• Confirm that the encounter is the "initial encounter" for this specific adverse reaction.