Adverse effect of pyrazolone derivatives, initial encounter

This code signifies a patient experiencing an unintended and harmful reaction to a pyrazolone derivative medication during the initial phase of treatment. These reactions are not due to an overdose or poisoning, but rather an adverse effect when the drug is administered correctly. Pyrazolone derivatives are a class of non-opioid analgesics and anti-inflammatory drugs.

Apply this code when documenting an allergic reaction, gastrointestinal upset, skin rash, or other adverse symptom directly attributable to a pyrazolone derivative, such as metamizole, during the patient's first encounter for this specific adverse event. This code is appropriate for initial assessment and management of the adverse effect.

• Always code the specific manifestation of the adverse effect first, followed by this code.
• Ensure documentation clearly states the adverse effect is due to a pyrazolone derivative and not an overdose or poisoning.
• Use a subsequent encounter code (T39.2X5D) for follow-up care related to the same adverse effect.