What Is Dizziness?
Almost everyone has had a feeling of unsteadiness or a whirling sensation in their heads at some point in their lives. Usually it's chalked up to dizziness, but dizziness is a broad term that can mean different things to different people. It's a common complaint, but it can be serious. Dizziness has no specific medical meaning, but there are four common conditions that can be considered types of dizziness:
- Vertigo . The feeling of motion when there is no motion, such as you spinning or your environment spinning. Spinning yourself round and round, then suddenly stopping, can produce temporary vertigo. But when it happens in the normal course of living, it signals a problem with the vestibular system of the inner ear -- the body's balance system that tells you which way is down and senses the position of your head. About half of all dizziness complaints are vertigo.
- Lightheadedness. Also called near syncope, lightheadedness is the feeling that you are about to faint. It is commonly felt by standing up too quickly, standing for too long such as in a line for the movies, or by breathing deeply enough times to produce the sensation.
- Disequilibrium. A problem with walking. People with disequilibrium feel unsteady on their feet or feel like they are going to fall.
- Anxiety . People who are scared, worried, depressed, or afraid of open spaces may use "dizzy" to mean frightened, depressed, or anxious.
Frequent dizziness sufferers may complain of more than one type of dizziness. For instance, having vertigo may also make them anxious.
Dizziness can be a one-time event, or it can be a chronic, long-lasting problem. Nearly everyone who is dizzy will get better. This is because a person's sense of balance is a complex interaction between the brain, each ear's separate vestibular system, sensors in the muscles, and sense of vision. When one component breaks down, the others usually learn to compensate.
What Causes Dizziness?
Vertigo can be caused by many things:
- Infection, such as the ones that cause the common cold or diarrhea, can cause temporary vertigo via an ear infection. This inner ear infection is generally viral, harmless, and usually goes away in one to six weeks, but drugs are available if it is severe.
- Benign paroxysmal positional vertigo -- positional vertigo or BPPV -- is caused by movement of an otolith -- a tiny calcium particle the size of a grain of sand -- from the part of the ear that senses gravity to the part that senses head position. The person feels as if their head is turning when it isn't. A two-minute therapy done right in the doctor's office can move the otolith back where it belongs and fix the problem. This therapy, called the Epley maneuver, cures vertigo 80% of the time.
- Meniere's disease is a disorder characterized by severe episodes of vertigo that come and go. Other symptoms of Meniere's disease are tinnitus (ringing in the ear), hearing loss, and pressure or fullness in the ear.
- Dandy's syndrome is a feeling of everything bouncing up and down. It can happen to people who take an antibiotic that is toxic to the ear. It usually improves over time.
- Less common, deadly diseases can also cause vertigo, such as tumors or stroke.
Lightheadedness is usually caused by some surrounding circumstance impairing blood flow to the brain when a person is standing up. Blame this problem on our ancestors who learned to walk upright -- putting our brain above our heart. It's a challenge for the heart to keep the brain supplied with blood -- and it's easy for this system to break down. Common causes include pooling of blood in your lower legs from sitting or standing too long, a very slow or very fast heart rate, low blood pressure from medications or nervous system dysfunction, blood pressure medications, and dehydration. Valve disease such as aortic stenosis can also cause a problem.
Disequlibrium can be caused by:
- A kind of arthritis in the neck called cervical spondylosis, which puts pressure on the spinal cord.
- Parkinson's disease or related disorders that cause a person to stoop forward.
- Disorders involving a part of the brain called the cerebellum. The cerebellum is the part of the brain responsible for balance and coordination.
- Diseases such as diabetes that can lead to loss of sensation in the legs.
Certain medications may cause vertigo while others could cause lightheadedness.