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.

Q: Acute chest pain is a common presentation in emergency.

A: non-adverse drug event
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Q: Reported here is an unusual case of radiation enteritis which caused a severe sequelae of stricture in the transverse colon as a long-term effect of therapeutic irradiation for uterine cancer, and required a surgical resection.

A: non-adverse drug event
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Q: Despite this improvement, the patient became resistant to the clozapine titration schedule due to complaints of sedation.

A:
non-adverse drug event
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