Many drugs used in anaesthesia depress respiration.

Opioids reduce the respiratory centre’s response to CO₂. Pinpoint pupils are often a clue that excessive amounts of opioids have been given.

Naloxone will antagonize the opioid-induced respiratory depression, but it will reverse the analgesic effects as well.

A relative or absolute overdose of benzodiazepines can be reversed with Flumazenil.

Doxapram, a ventilatory stimulant, can be considered for non-specific respiratory depression.

Often the volatile agent contributes to hypoventilation, so ensure there has been adequate washout of these agents. Their level can be determined on the monitor.