Alternate Names : Sleepiness
Drowsiness is a state of decreased awareness or alertness
associated with a desire or tendency to fall asleep.
What is going on in the body?
Almost everyone has felt drowsy
before, usually due to normal tiredness from a long day or lack of sleep. There are other causes of this condition as well. Most of the causes are not serious, but some are life threatening.
What are the causes and risks of the condition?
There are many possible causes of this condition, including:
lack of sleep or sleep disorders, such as insomnia and sleep apnea. Sleep apnea is a disorder of breathing during sleep that prevents a person from getting enough rest.
infections, such as chronic bronchitis or infectious mononucleosis
a low red blood cell count, called
working, studying, or exercising too much
lack of exercise or poor physical conditioning
hormone imbalances, such as hypothyroidism, a condition caused by a low level of thyroid hormone
depression or other
autoimmune disorders, or
conditions in which a person's immune system attacks his or her own body.
Examples include systemic lupus erythematosus and rheumatoid arthritis.
low oxygen levels in the blood, which can occur with heart disease or chronic obstructive pulmonary disease
toxin or chemical exposure, such as carbon monoxide poisoning
medications, such as antihistamines, sedatives, and certain medications
used to treat depression and high blood pressure
systemic disorders, such as uncontrolled diabetes
a stroke, or brain attack
any severe, life-threatening illness, such as meningitis, severe pneumonia, or end-stage cancer
Other causes are also possible. Sometimes no cause can be found.