Dear Doctor, Recently on my way to office, I felt dizzy and fainted while on a bus. I have no history of any medical condition and I jog regularly. What could have caused this? Jeff, 35 years Dear Jeff, Most likely you could have suffered from low blood pressure, which caused the fainting and dizziness. A low blood pressure could be due to skipping meals, diarrhea and or vomiting, taking a pill/pills for high blood pressure, standing continuously for long hours, are the common reasons. Some people suffer from postural hypotension, i.e. due to sudden change in position like standing up from a sitting position, causes pooling of blood in the legs, resulting in dizziness. Low blood sugar due to any reason can also cause dizziness and fainting. Trauma or infection of the inner ear, can cause dizziness. It is commonly accompanied by spinning sensation of the head, perceived sounds inside the ear and nausea with or without vomiting. Chronic anemia can cause dizziness on exertion. Hypothyroidism can cause dizziness as one of the manifestations. Transient ischemic attack(TIA) is a serious medical disorder, causing transient dizziness. It occurs due to transient blocking of blood supply of brain, either due to a clot or fat deposits inside the blood vessels. Abnormalities of the heart beat tend to affect the blood supply of the brain, causing dizziness.
