The causes of lightheadedness include changing position, dehydration, allergies, low blood sugar and illness, according to Healthline. The usage of tobacco, alcohol or drugs can also lead to lightheadedness.
In many cases, lightheadedness happens because a person switches rapidly from sitting to standing, explains Healthline. The abrupt movement causes decreased blood flow to the brain and can also make a person faint. Altitude sickness, having a cold or the flu, and some medications can also lead to lightheadedness. It can also indicate more serious health problems, including heart conditions and stroke.
While lightheadedness is often not a cause for concern, a person should seek medical assistance if he has also lost a lot of blood, says Healthline. A person should also get medical assistance if signs of heart attack or stroke accompany the lightheadedness. Such signs include facial drooping, nausea, chest pressure or pain, and vomiting. In such cases, a person should call 911 and not drive himself anywhere. Other cases in which a person should seek help is if the lightheadedness has continued for more than a week or if it has caused injury or nausea. To avoid the common causes of lightheadedness, a person should stand slowly, drink lots of water and avoid alcohol and tobacco.