We all feel tired sometimes, but roughly 20 percent of the population can be classified as having Excessive Sleepiness (sometimes referred to as Excessive Daytime Sleepiness).
Excessive sleepiness is the leading complaint of patients who visit sleep clinics. People who have excessive sleepiness feel drowsy and sluggish most days, and these symptoms often interfere with work, school, activities, or relationships. Although patients with this condition often complain of "fatigue," excessive sleepiness is different from fatigue, which is characterized by low energy and the need to rest (not necessarily sleep). Excessive sleepiness is also different from depression, in which a person may have a reduced desire to do normal activities, even the ones they used to enjoy.
Excessive sleepiness is not a disorder in itself—it is a serious symptom that can have many different causes. If you feel excessively sleepy, you and your doctor should investigate it further. The common causes are poor sleep habits, such as reduced opportunity for sleep or irregular sleep schedule, a sleep disorder like obstructive sleep apnea, side effects from certain medications, and other underlying medical conditions. Once you and your doctor have determined the cause of excessive sleepiness, you can create a treatment plan together. For most people, that involves changing sleep habits and improving behaviors and elements of the sleep environment. For others, further medical tests or sleep studies may be indicated.
If you are frequently tired, work less productively, make mistakes, have lapses in judgment or wakefulness, or feel unable to enjoy or fully participate in life's activities, don't just "push through." If you've been excessively tired for a long time, it may feel normal to you, but poor sleep and resulting excessive sleepiness can have drastic, long-term effects on your health (for example reduced sleep is tied to cardiovascular problems and weight gain), as well as how you think and feel. Not only that, when you go about your day overtired, you put yourself and others at risk, since motor vehicle accidents and other dangerous errors are often caused by sleepiness. If you're feeling the symptom of excessive sleepiness, talk to your doctor so the two of you can take a closer look at your sleep habits and take steps to improve your health, and ultimately get you on the road to sleeping and feeling better.