About remifentanilultra short acting synthetic opioid analgesicsmechanism of action of remifentanilremifentanil is a specific mu-type-opioid receptor agonist. hence, it causes a reduction in sympathetic nervous system tone, respiratory depression and analgesiaindications for remifentanil1.analgesia during induction of anaesthesia 2.continuation of analgesia into immediate post operative period interactions for remifentanilincreased cns depression with inhaled and iv anaesthetics, benzodiazepines increased hypotension and bradycardia with cardiac depressants (e.g. ?-blockers, calcium channel blockers) increased cns depressant with sodium oxybate