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: PURPOSE: Symptomatic visual field constriction thought to be associated with vigabatrin has been reported.

A: adverse drug event
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Q: After ruling out a hydrotelluric source of fluorine, the patient's fluorosis was linked to chronic use of niflumic acid, following the publication in 1978 of the 2 previously reported cases affected by this drug.

A: adverse drug event
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Q: It gives the radiological and CT scan findings and the important role played by them in the diagnosis of this syndrome.

A:
non-adverse drug event
****
