Drug and dose dependent, but generally include:
Hypotension
Respiratory depression
Withdrawal
Delirium
Arrhythmias
Hypotension
Respiratory depression
Withdrawal
Delirium
Arrhythmias
ICU sedation
Procedural sedation
Procedural sedation 
Trauma sedation
Post cardiac arrest care
Advanced airway adjuncts
Anticonvulsant levels and reloading
Therapeutic hypothermia