28th May 2025

A 56-year-old man with lung cancer has come in due to pain and vomiting.

A 56-year-old man with lung cancer has come in due to pain and vomiting. He has been commenced on a syringe driver and has had his dose increased from 20mg to 60mg in the last 4 days. He already takes gabapentin 300mg TDS and clonazepam for neuropathic pain. His urine output has been dwindling, and his last urea and electrolytes showed an AKI stage 2.

On review, he is extremely drowsy with a respiratory rate of 8. He is arousable to voice.

Which of the following is not a risk factor for him to develop opioid toxicity?

Select the SINGLE most appropriate option from the list below. Select ONE option only.