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: Two patients who developed decreased visual acuity after several months of ethambutol treatment for Mycobacterium avium-intracellulare infection had bitemporal visual field defects that suggested optic chiasm damage.

Answer: adverse drug event


Question: A healthy, 30-year-old man, exposed to sulindac on two separate occasions, had an incapacitating isolated idential sensory neuropathy.

Answer: adverse drug event


Question: Seven patients only smoked at night-time (median dose eight puffs, range two to eight puffs), and eight patients used cannabis mainly during the day (median dose three puffs, range two to eight puffs); the median frequency of use was four times per day (range one to 16 times per day).

Answer:
non-adverse drug event