Opioid toxicity following a therapeutic dose of dihydrocodeine: A case report

Dihydrocodeine (DHC) is a synthetic analogue of codeine used in the treatment of moderate to severe pains. However, it has safety concerns to draw attention to the possible occurrence of DHC toxicity even in therapeutic doses. An 84-year-old known diabetic, hypertensive, and hormone-refractory, advanced carcinoma of the prostate male patient were admitted to our ICU for pain management and close monitoring. Shortly before admission, he had received DHC 60 mg in the surgical ward, which was to be followed with 30 mg 8 hourly. Within 10 hours of admission, he developed a classic triad of features of opioid toxicity (respiratory depression, coma, and pinpoint pupils). He was managed with naloxone at 0.4 mg and another 0.4 mg, 10 minutes later. The patient recovered initially and then relapsed into a coma after a short while before the next dose of naloxone was given and could not be resuscitated. Opioid toxicity even with therapeutic doses of DHC can occur during treatment.