Good Day! My Brother Was Having Toothache, Rushed To The

Good day! My brother was having toothache, rushed to the dentist and was prescribed with Klavox 650. Taken per orem in one week duration. After taking the prescribed medication, patient complains of being nauseous accompanied with vomiting, stomach cramping and bloating.. Should he continue taking it or should he just abruptly stop? I hope I get a quick response from you.. Thanks..