Difficulty falling asleep and staying asleep
Impaired daytime function (must also be reported for a diagnosis of an<unk>  disorder)
Simultaneous psychiatric, medications/substances, are usually present
Insomnia
Alcohol Abuse, alcohol, benzo, or opioid withdrawal
Ergotism
Depression/anxiety
Sedation 
Bipolar disorder, schizophrenia
Hiccups
Hepatic encephalopathy