What Causes Metallic Taste In The Mouth And Nausea?

My daughter-in-law, age 22 is having a metallic taste in her mouth and symptoms of feeling car sick for the past 4 days in the sense of the nausea that invisions. She does take seizure medicine but it has not been changed for a long period of time. Should she be seeing a doctor, drinking water or electolytes, or ???????????