Common causes of sudden dizziness include benign paroxysmal positional vertigo, inner-ear inflammation, blood pressure drops, structural inner-ear abnormalities and anxiety disorders, explains Mayo Clinic. Other potential causes include certain medications, low blood-iron levels, low blood sugar, dehydration and vestibular migraines.
There are several different types of dizziness, each with its own set of typical triggers, notes Mayo Clinic. Vertigo is one type of dizziness, and it produces a spinning feeling or a feeling that the surroundings are spinning, explains WebMD. Benign paroxysmal positional vertigo, a condition in which calcium crystals gather in the inner ear canals, is the most common reason people experience vertigo. Vestibular migraines, a type of tumor called acoustic neuromas, and Meniere's disease can also produce the sensation of vertigo.
Another type of dizziness is faintness or lightheadedness, explains Mayo Clinic. Common reasons for feeling faint include dips in blood pressure and heart conditions that cause the heart to pump inadequate amounts of blood. Yet another form of dizziness is called disequilibrium, and it involves losing balance or feeling off-balance while walking. Disequilibrium can result from inner-ear abnormalities; certain medications, such as anti-seizure drugs and tranquilizers; muscle weakness; and neurological diseases, such as Parkinson's disease.
Patients sometimes describe their dizziness as a general brain fog or spacey feeling, notes Mayo Clinic. This variation of dizziness often results from high blood pressure medications, anxiety disorders, iron-deficiency anemia or low blood sugar levels.