Dizziness and Drowsiness are two common symptoms that are used interchangeably by many patients. Since they sound similar, many patients think that they are one and the same thing. Let us understand the difference between the two words.
Dizziness
Usually a patient goes to the physician with a complaint of loss of balance, unsteadiness, instability, the world spinning around him or the feeling that he is about to faint. All these symptoms come under the umbrella of dizziness.
Causes of Dizziness
Dizziness is a common symptom in people suffering from middle ear and inner ear disorders like labrynthitis, benign paroxysmal positional vertigo. Since there is mismatch of the signals received by eyes and the vestibular apparatus of the inner ear (organ responsible for balance), the patient is confused about the position of his head and body in space leading to dizziness or the spinning feeling. Dizziness is also felt by people when they suddenly come upright from the lying down position. Sudden change in posture leads to fall in blood pressure resulting in reduced blood flow to the brain. Hence the patient feels dizzy. This phenomenon is known as postural hypotension. Other conditions that may cause dizziness include anxiety, tension, arteriosclerosis (hardening of arteries) anaemia, heart rhythm irregularities and excess salt. All these factors reduce blood circulation causing decreased blood supply to the heart and brain which causes the patient to feel faint. Head injury is another important reason for dizziness. Sometimes dizziness can be due to side effects caused by certain medications also. Consumption of caffeine and nicotine also causes dizziness as it affects blood circulation.
Drowsiness
This is a state of excessive sleepiness. It is also known as somnolence or narcolepsy. A patient suffering from drowsiness is unable to ward off the sleepy feeling during the day and has difficulty in remaining alert. The patient finds it very difficult to keep his eyes open. He has very low mental agility, poor cognition, physical weakness and perennial lethargy. It signifies a serious medical condition.
Causes of Drowsiness
Drowsiness can occur due to disturbed sleep, sleep apnoea, insomnia, irregular sleep cycles, irregular work shifts etc. Insufficient sleep at night due to any of the above reasons makes the person sleepy in the day time. Resolving sleep apnoea and following correct bed time routine can help to solve such drowsiness. Many a time people are surrounded with tensions, anxiety or have undergone mental breakdown. Such persons also experience drowsiness. It can be considered a defence mechanism to stop them from thinking about their problems. Drowsiness is a common side effect of medicines such as tranquilisers, sedatives, anti-anxiety, antidepressants etc. Expectorants that relieve cough and cold also cause drowsiness as they depress the central nervous system.
To summarise we can say that dizziness encompasses syncope, imbalance and swirly feeling whereas drowsiness is a state of excessive uncontrolled sleep. Treatment of middle and inner ear disorders, blood pressure regulation and correction of anaemia can help resolve the problem of dizziness in majority of cases.