According to MedicinePlus, night terrors are a common cause of screaming in one's sleep. While most common in children, adults can also suffer from night terrors.
MedicinePlus states that although the underlying reasons for night terrors are mostly unknown, there are common triggers. Periods of emotional stress or conflict, fever and lack of sleep can all cause night terrors. Adult night terrors are often precipitated by emotional stress or alcohol use. Night terrors usually occur within the first third of the night, around 90 minutes after falling asleep.
WebMD states that unlike nightmares, night terrors occur during non-REM sleep. Screaming and panic are common, as are rapid breathing, rapid heartbeat and sweating. Individuals experiencing night terrors may not respond to comfort from others or attempts to wake them up. Upon waking in the morning, people experiencing night terrors often have no memory of the episode or what they were experiencing during the episode.
According to MedlinePlus, if night terrors occur often and disrupt sleep on a regular basis, seeking professional medical help is advised. A physician may refer a patient with night terrors to a sleep clinic to rule out physiological causes. Psychiatrists can provide medications and utilize talk therapy to help alleviate night terrors.