Certified Hospice and Palliative Assistant (CHPNA) Practice Test

What does methylnaltrexone inhibit in patients on opioids?

1. Urinary retention

2. Opioid-induced gastrointestinal slower motility

3. The sensation of pain

4. Blood clot formation

The correct answer is: Opioid-induced gastrointestinal slower motility

Methylnaltrexone is a medication specifically designed to treat opioid-induced gastrointestinal slowing, or reduced motility, in patients who are using opioids for pain management. Opioids often cause constipating effects by binding to opioid receptors in the gastrointestinal tract, which leads to decreased gut motility and the potential for constipation. Methylnaltrexone works as a peripherally acting opioid receptor antagonist. It selectively blocks the action of opioids in the gut without affecting their pain-relieving effects in the central nervous system. By inhibiting this action at the gastrointestinal level, methylnaltrexone facilitates bowel movements and relieves the discomfort associated with constipation caused by opioid use. The other options are not the primary effects of methylnaltrexone. For example, while it indirectly affects urinary retention linked to opioid use, it does not specifically inhibit this effect as its primary action. Methylnaltrexone does not alter the sensation of pain, since its action is targeted to the gastrointestinal system. Lastly, it does not have a role in inhibiting blood clot formation, which is unrelated to its function as an opioid antagonist. Thus, the main and correct role of methylnaltrexone is to alleviate opioid-induced