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: Ibuprofen-induced meningitis: detection of intrathecal IgG synthesis and immune complexes.

A: adverse drug event
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Q: We are concerned that the macular lesion was a retinal toxic effect of gentamicin because of the recent description of similar lesions occurring after the inadvertent intraocular injection of massive doses of this drug.

A: adverse drug event
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Q: Warfarin-associated bleeding generally is considered deleterious; however, in our patient it unmasked an early stage of colon cancer and thus may have saved the patient's life.

A:
adverse drug event
****