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.

We describe 2 male patients, a 49-year-old with psoriatic arthritis and impaired renal function and a 43-year-old renal transplant recipient, who both sustained a marked decline in glomerular filtration rate in conjunction with a selective inhibitor of cyclooxygenase-2 (COX-2), rofecoxib.
adverse drug event

These patients were treated by the continuous administration of an estrogen-progestogen combination for 6 months.
non-adverse drug event

Central nervous system imaging was negative.

non-adverse drug event

