In addition to the main symptoms of DSPS, most people with DSPS also have some or all of the following features:

1. DSP individuals are night owls. They feel most alert and say they function best, are most creative, etc. in the evening and at night.
2. They usually have tried many times to change their sleeping schedule. Failed tactics to sleep at earlier times may include relaxation techniques, early bedtimes, hypnosis, alcohol, sleeping pills, dull reading, and folk remedies. They often have asked family members to help wake them in the morning, or they have used several alarm clocks. Or family members - especially parents - have tried to get them up on time.
3. Symptoms often begin in adolescence, childhood, or infancy.
4. They are sleepy during the day, especially in the morning, if they have had to get up early. They sleep in on weekends (often past noon and for more than 10 hours) to make up for not getting enough sleep during the rest of the week. Some people with DSPS take naps during the day and feel refreshed afterwards.
5. Many people with DSPS need at least 30 minutes to fall asleep, even when they go to bed at a time that is realistic for them.
6. Some people with DSPS have occasional, sudden, and temporary reversions to sleeping at earlier times.