Adverse drug reactions are appreciably harmful or unpleasant reactions resulting from an intervention related to the use of medical products, which predicts hazard from future administration and warrants prevention or specific treatment, or alteration of the dosage regimen, or withdrawal of the product. Given medical case reports extracted from MEDLINE, the task is to classify whether the case report mentions the presence of any adverse drug reaction. Classify your answers into non-adverse drug event and adverse drug event.
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Question: Chronic hydroxychloroquine use associated with QT prolongation and refractory ventricular arrhythmia.

Answer: adverse drug event


Question: Adenomyosis confined to the broad ligament is extremely rare.

Answer: non-adverse drug event


Question: Two years later, 24 hours following an increase in the dose of disopyramide from 300 to 600 mg/day, AVT with syncope occurred; isoproterenol abolished the arrhythmia instantly.

Answer:
adverse drug event