Question

Oxycodone is an opioid analgesic that is able to provide an analgesic effect by acting as an agonist at the mu-opioid receptors

Sedation (i.e. feeling sleepy) is reported to be a common ‘on-target’ adverse effect of oxycodone. Is sedation likely to be an adverse effect of other drugs with the same drug class (e.g. morphine, fentanyl)? Briefly explain your reasoning.

Answer 1

Oxycodone is a semi synthetic opioid derivative. It acts on mu receptor as an agonist and causes sedation. Sedation is the feature of both mu and kappa receptors. Both these receptors' stimulation produce sedation. All the opiods like morphine (prototype) , fentanyl, methadone, tramadol, etc. act on mu receptors and kappa receptors and produce sedation. This sedation is a double edged sword. It can be a side effect or can be used as an action of opiates in pre-anaesthetic preparation of the patient.