Adverse effect of diagnostic agents, initial encounter

This code signifies an undesirable or harmful reaction experienced by a patient following the administration of a substance primarily used for diagnostic purposes. This reaction is not an allergic response but rather an expected or unexpected side effect of the diagnostic agent itself. This specific code is used when the patient is receiving active treatment for the adverse effect.

Apply this code when a patient presents with symptoms such as nausea, dizziness, rash, or organ dysfunction directly attributable to a diagnostic agent (e.g., contrast media, radiopharmaceuticals, or other testing agents) during their initial encounter for treatment. This includes situations where the adverse effect is identified and managed for the first time.

• Always sequence this code first when it is the primary reason for the encounter.
• Do not use this code for allergic reactions; refer to the appropriate T36-T50 codes with the 1 or 2 5th or 6th character for poisoning or adverse effect.
• Ensure documentation clearly links the adverse effect to a specific diagnostic agent and indicates the initial phase of care.