Feeling nauseous and dizzy can be caused by a variety of reasons, ranging from temporary and minor issues to more serious conditions. Common causes include anxiety or stress, inner ear problems that affect balance, stomach viruses or infections leading to dehydration, low blood sugar, migraines, motion sickness, and side effects of medications. Other possible causes include dehydration, electrolyte imbalances, pregnancy (morning sickness), alcohol or drug effects, and certain neurological or cardiac conditions. Usually, these symptoms suggest a less serious problem like an inner ear infection or mild dehydration, but persistent or severe dizziness and nausea should be evaluated by a healthcare professional to rule out serious issues.