Lightheadedness is a common and typically unpleasant sensation of

dizziness Dizziness is an imprecise term that can refer to a sense of disorientation in space, vertigo, or lightheadedness. It can also refer to disequilibrium or a non-specific feeling, such as giddiness or foolishness. Dizziness is a common medical ...

or a feeling that one may faint. The sensation of lightheadedness can be short-lived, prolonged, or, rarely, recurring. In addition to dizziness, the individual may feel as though their head is weightless. The individual may also feel as though the room is "spinning" or moving (

vertigo Vertigo is a condition where a person has the sensation of movement or of surrounding objects moving when they are not. Often it feels like a spinning or swaying movement. This may be associated with nausea, vomiting, sweating, or difficulties ...

). Most causes of lightheadedness are not serious and either cure themselves quickly, or are easily treated. Keeping a sense of balance requires the

brain The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head ( cephalization), usually near organs for special ...

to process a variety of information received from the

eyes Eyes are organs of the visual system. They provide living organisms with vision, the ability to receive and process visual detail, as well as enabling several photo response functions that are independent of vision. Eyes detect light and c ...

, the

nervous system In Biology, biology, the nervous system is the Complex system, highly complex part of an animal that coordinates its Behavior, actions and Sense, sensory information by transmitting action potential, signals to and from different parts of its ...

, and the inner ears. If the brain is unable to process these signals, such as when the messages are contradictory, or if the

sensory system The sensory nervous system is a part of the nervous system responsible for processing sensory information. A sensory system consists of sensory neurons (including the sensory receptor cells), neural pathways, and parts of the brain involved ...

s are improperly functioning, an individual may experience lightheadedness or dizziness. Lightheadedness is very similar to pre-syncope. Pre-syncope is the immediate stage before syncope (fainting), particularly in cases of temporary

visual field The visual field is the "spatial array of visual sensations available to observation in introspectionist psychological experiments". Or simply, visual field can be defined as the entire area that can be seen when an eye is fixed straight at a point ...

loss (i.e. vision getting "dark" or "closing in").

Causes

Lightheadedness can be simply (and most commonly) an indication of a temporary shortage of

blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in th ...

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as we ...

to the brain due to a drop in

blood pressure Blood pressure (BP) is the pressure of circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term "blood pressur ...

, rapid

dehydration In physiology, dehydration is a lack of total body water, with an accompanying disruption of metabolic processes. It occurs when free water loss exceeds free water intake, usually due to exercise, disease, or high environmental temperature. Mi ...

from

vomiting Vomiting (also known as emesis and throwing up) is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Vomiting can be the result of ailments like food poisoning, gastroenteri ...

diarrhea Diarrhea, also spelled diarrhoea, is the condition of having at least three loose, liquid, or watery bowel movements each day. It often lasts for a few days and can result in dehydration due to fluid loss. Signs of dehydration often begin ...

, or

fever Fever, also referred to as pyrexia, is defined as having a temperature above the normal range due to an increase in the body's temperature set point. There is not a single agreed-upon upper limit for normal temperature with sources using val ...

. Other causes are: altitude sickness, low blood sugar,

hyperventilation Hyperventilation is irregular breathing that occurs when the rate or tidal volume of breathing eliminates more carbon dioxide than the body can produce. This leads to hypocapnia, a reduced concentration of carbon dioxide dissolved in the blood. ...

, postural orthostatic tachycardia syndrome,

panic attacks Panic attacks are sudden periods of intense fear and discomfort that may include palpitations, sweating, chest pain or chest discomfort, shortness of breath, trembling, dizziness, numbness, confusion, or a feeling of impending doom or of losing ...

, and

anemia Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, ...

. It can also be a symptom of many other conditions, some of them serious, such as heart problems (including abnormal heart rhythm or

heart attack A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which m ...

), respiratory problems such as pulmonary hypertension or

pulmonary embolism Pulmonary embolism (PE) is a blockage of an artery in the lungs by a substance that has moved from elsewhere in the body through the bloodstream (embolism). Symptoms of a PE may include shortness of breath, chest pain particularly upon breathing ...

, and also stroke, bleeding, and shock. If any of these serious disorders is present, the individual will usually have additional symptoms such as

chest pain Chest pain is pain or discomfort in the chest, typically the front of the chest. It may be described as sharp, dull, pressure, heaviness or squeezing. Associated symptoms may include pain in the shoulder, arm, upper abdomen, or jaw, along with ...

, a feeling of a racing heart, loss of speech or change in vision. Many people, especially as they age, experience lightheadedness if they arise too quickly from a lying or seated position. Lightheadedness often accompanies the flu,

hypoglycaemia Hypoglycemia, also called low blood sugar, is a fall in blood sugar to levels below normal, typically below 70 mg/dL (3.9 mmol/L). Whipple's triad is used to properly identify hypoglycemic episodes. It is defined as blood glucose be ...

, common cold, or

allergies Allergies, also known as allergic diseases, refer a number of conditions caused by the hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic derm ...

. Dizziness could be provoked by the use of

antihistamine Antihistamines are drugs which treat allergic rhinitis, common cold, influenza, and other allergies. Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provide ...

drugs, like levocetirizine, or by some antibiotics or

SSRI Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions. SSRIs increase the extrace ...

s. Nicotine or tobacco products can cause lightheadedness for inexperienced users. Narcotic drugs, such as codeine, can also cause lightheadedness.

Treatment

Treatment for lightheadedness depends on the cause or underlying problem. Treatment may include drinking plenty of water or other fluids (unless the lightheadedness is the result of water intoxication in which case drinking water is quite dangerous). If a patient is unable to keep fluids down from nausea or vomiting, they may need intravenous fluids such as Ringer's Lactate. They should try eating something sugary and lying down or sitting and reducing the elevation of the head relative to the body (for example, by positioning the head between the knees). Other simple remedies include avoiding sudden changes in posture when sitting or lying and avoiding bright lights. Several essential electrolytes are excreted when the body perspires. When people experience unusual or extreme heat for a long time, sweating excessively can cause a lack of some electrolytes, which in turn can cause lightheadedness.

References

External links

The MedlinePlus Medical Encyclopedia
{{Cognition, perception, emotional state and behaviour symptoms and signs Symptoms and signs of mental disorders

Causes

Treatment

See also

References

External links