Dehydration

• When experiencing light-headedness or dizziness, the first thing you should ask yourself is if you're dehydrated. Dizziness is one of the first and most common side effects from dehydration. If you've been experiencing diarrhea or vomiting, you may very well be dehydrated. Dehydration is usually the cause for short bouts of dizziness, and the symptoms are most intensely experienced when sitting up or moving your head quickly.
  
  

Blood Pressure

• Dizziness is also commonly associated with high or low blood pressure. If you've eaten a heavy meal, lain down for a long time and gotten up quickly or did a lot of strenuous work, you may experience some dizziness. If the dizziness persists, or comes on suddenly without any provocation, it may be vertigo.
  
  

Vertigo

• Vertigo is usually defined as the sensation of spinning or whirling, either yourself or the room around you. It's usually caused by a disturbance in your vestibular system in the inner ear. Symptoms can last from a few seconds to a few minutes, and are usually experienced intermittently.
  
  

Labyrinthitis

• Commonly caused by viral or sometimes even bacterial infections, Labyrinthitis is a common culprit of acute vertigo. The infection is called Labyrinthitis because the virus or bacteria affects the Labyrinth located in the vestibular system of the inner ear. The vestibular system senses changes in rotational movement, thus explaining the cause of vertigo. Many times, Labyrinthitis will go away on its own, but you may need an antibiotic from your doctor to clear up an infection at the root of the problem. Always speak with your doctor about which treatment is right for you.