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.

Example Input: Escape atrial complexes, which occurred following junctional premature complexes, failed to initiate tachycardia in the control state but tachycardia was always reinitiated by an identical escape sequence after procainamide.
Example Output: adverse drug event

Example Input: Acute chest pain is a common presentation in emergency.
Example Output: non-adverse drug event

Example Input: Histological improvement with lamivudine therapy for de novo hepatitis B occurring in an anti-HBs-positive child after bone marrow transplantation.
Example Output:
non-adverse drug event

