Final answer:
The nurse would recommend increasing fluids and high-fiber foods and using a mild laxative to manage constipation caused by morphine, a common side effect of this and other opioids like oxycodone and codeine.
Step-by-step explanation:
If a client with cancer pain is taking morphine for pain relief and is experiencing constipation, the nurse would recommend option B: "Increase fluids and high-fiber foods, and use a mild laxative." This advice takes into account that opioids like morphine, as well as others such as oxycodone and codeine, commonly cause constipation as a side effect. The nurse's suggestion aims to proactively manage the symptoms through dietary modifications and over-the-counter remedies.
To alleviate the issue, increasing the intake of liquids can help soften stool, while high-fiber foods can help increase the bulk and frequency of bowel movements. Moreover, if diet alone is insufficient, a mild laxative can be used to aid in easing bowel movements. However, enemas are typically not recommended for regular use without consultation with a healthcare provider, and ignoring constipation is not advisable since it can lead to more serious complications.