A 72-year-old man arrives at the office due to constipation. His stools have been harder, smaller, and more challenging to pass. Bloating has been linked to this, but not vomiting. Despite fiber supplements, polyethylene glycol, and bisacodyl, symptoms have not subsided. The patient received palliative chemotherapy two months ago after being recently diagnosed with metastatic pancreatic cancer. His malignancy produces excruciating stomach discomfort that requires to be treated with high-dose oxycodone. Vital indicators are in the expected range. The abdomen is mildly distended with decreased bowel sounds. Which of the following medications acts as a mu-opioid receptor antagonist that could alleviate this patient's constipation without inducing withdrawal symptoms?

Question

A 72-year-old man arrives at the office due to constipation. His stools have been harder, smaller, and more challenging to pass. Bloating has been linked to this, but not vomiting. Despite fiber supplements, polyethylene glycol, and bisacodyl, symptoms have not subsided. The patient received palliative chemotherapy two months ago after being recently diagnosed with metastatic pancreatic cancer. His malignancy produces excruciating stomach discomfort that requires to be treated with high-dose oxycodone. Vital indicators are in the expected range. The abdomen is mildly distended with decreased bowel sounds.  Which of the following medications acts as a mu-opioid receptor antagonist that could alleviate this patient's constipation without inducing withdrawal symptoms?

Quizplus · Accepted Answer

Eductional Objective: Methylnaltrexone, a peripherally acting -opioid receptor antagonist that counteracts opiates' anti-peristaltic effects, may be helpful for people with refractory opioid-induced constipation. It is unable to cross the blood-brain barrier; as a result, it has no effect on opiate withdrawal symptoms. This makes it possible to treat OIC without impairing analgesic effects.

A 72-Year-Old Man Arrives at the Office Due to Constipation