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: PURPOSE: To describe bilateral optic neuritis that occurred as an adverse effect of recombinant and natural interferon alpha administration.

Answer: adverse drug event


Question: We report a case of a patient with rheumatoid arthritis treated with low-dose methotrexate (15 mg/week) who developed infection with both M. tuberculosis and M. chelonae after the revision of a prosthetic hip.

Answer: adverse drug event


Question: Visual changes, headache, and elevated blood pressures were present on arrival to the emergency department.

Answer:
non-adverse drug event