Feeling lightheaded occurs because the brain is not receiving enough blood or oxygen temporarily. Common causes include a sudden drop in blood pressure, especially when standing up quickly (orthostatic hypotension); dehydration; low blood sugar; illness like cold or flu; medication side effects; anxiety or stress; and heat exposure. More serious causes can involve heart problems, internal bleeding, or neurological conditions, but these usually come with additional symptoms. To reduce lightheadedness, suggestions include rising slowly from sitting or lying positions, staying hydrated, eating sugary or carbohydrate-rich foods when faint, and resting until the feeling passes. If lightheadedness is frequent, prolonged, or accompanied by other concerning symptoms, medical evaluation is recommended.
