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.

Example Input: The present report illustrates a rare case of refractory akathisia after interferon-alpha treatment and also that levodopa treatment would be theoretically and practically useful in reducing the neurotoxicity associated with interferon-alpha.
Example Output: adverse drug event

Example Input: However, other factors or drugs (e.g. cresol) are thought to induce MH.
Example Output: adverse drug event

Example Input: Antitumor activity was observed in four patients.
Example Output:
non-adverse drug event