In the evening of Monday last week, my father suddenly dizzied and vomited while he was on walk.Meanwhile, he felt faint and numbness. After examinations including CT,DWI,MRI and MRA, it shows no problem in his brain,spine and heart.But from last Thursday, he dizzies and vomits seriously everyday. Each time it begins with palpitation and lasts 2 or 3 hours. One doctor suggests the cause is anxiety and should take anti-anxiety medication including lorazepam tablets. But after several times treatment, there is no improvement at all.Could you help to give us some suggestions about this situation.