Dizziness covers different sensations. Vertigo, a spinning feeling, is commonly due to inner-ear conditions such as benign positional vertigo or a viral labyrinthitis. Lightheadedness, like you might faint, often comes from dehydration, low blood sugar, low blood pressure, standing up quickly, anxiety, or certain medicines. Anemia and heart-rhythm problems can also cause it.
Most dizziness settles on its own or with simple measures like sitting down, hydrating, and rising slowly. See a doctor if dizziness is frequent, severe, recurrent, or comes with hearing loss, ringing in the ears, vomiting you cannot control, or falls.
Call your local emergency number if dizziness comes on suddenly with a severe headache, slurred speech, facial droop, weakness or numbness on one side, double vision, trouble walking, chest pain, or fainting — these can signal a stroke or heart problem. This is general information only.