If you develop dizziness that lasts for more than a few seconds, check with your doctor. it could be a stroke. Recurrent dizziness can be caused by temporary interruption of circulation to your brain, such as blocked neck arteries or an irregular heart beat. It can be caused by a stroke, tumors on the hearing nerve or brain, drug reactions, a bang on the head, an infection in the inner ear or anything that interferes with nerve function such as lack of vitamin B12, diabetes, migraine, seizures, or infections such as herpes or chicken pox.
Dizziness lasting for a day or longer is usually due to nerve damage called neuritis and often gets better without treatment; or to a stroke which often does not get better and is associated with reduced vision. If you have any reason to think that your dizziness may be the symptom of a stroke, you must seek treatment immediately because shutting off the blood supply to a part of your brain called the cerebellum can cause progressive swelling and death if it is not treated immediately. Dizziness lasting for minutes or a few hours usually is due to temporary obstruction of the blood supply to the brain called transient ischemic attacks, migraine or seizures. If it continues or recurs, it is often due to Meniere's syndrome which includes reduced hearing, ringing in the ears and a feeling of pressure in the ears.
Dizziness lasting a few seconds is usually due to a debris in your balance apparatus in your inner ear, called benign positional vertigo and is cured by special rapid movements of the head (3,4). Meniere's syndrome is treated with rest and probably a prescription for scopolamine. Your doctor may also try antihistamines such as cyclizine or meclizine, tranquilizers such as Valium, anticonvulsants such as Dilantin, or migraine medications such as Imitrex. If your dizziness and other symptoms are severe enough, your doctor may give you a drug to damage your hearing nerve permanently.
Dehydration is a common cause of dizziness in older people, particularly those who take diuretics.
Dizziness that lasts only a few seconds is often caused by a Slow Heart Rate.
1) NEJM September 3, 1998 .
2) WPR Gibson, IK Arenberg. Pathophysiologic theories in the etiology of Meniere's disease. Otolaryngologic Clinics of North America 30: 6 (DEC 1997):961. A new theory suggests that a narrowed duct becomes obstructed by debris that is cleared by a combination of the secretion of hydrophillic proteins within the sac and a hormone, saccin, that increases the volume of endolymph within the cochlea. It is proposed that the sudden restoration of longitudinal flow initiates the attacks of vertigo.
3) E Mira, S Mauri. Paroxysmal positional vertigo. Italian Journal of Neurological Sciences 19: 3(JUN 1998):150-160. posterior semicircular canal (PSC-PPV) and horizontal semicircular canal PPV (HSC-PPV).
4)V Honrubia, RW Baloh, MR Harris, KM Jacobson. Paroxysmal positional vertigo syndrome. American Journal of Otology, 1999, Vol 20, Iss 4, pp 465-470