<unk>  is a potent, short-acting synthetic opioid analgesic drug. It is given to patients during surgery to relieve pain and as an adjunct to an anaesthetic.<unk>  is used for sedation as well as combined with other medications for use in general anesthesia. The use of<unk>  has made possible the use of high-dose opioid and low-dose hypnotic anesthesia, due to synergism between<unk>  and various hypnotic drugs and volatile anesthetics.
Remifentanil
Propofol
Fentanyl
Etomidate
Alfentanil
Ketamine
Metharbital
Sevoflurane