Final answer:
b. Abdominal pain
The nurse should withhold exenatide and notify the provider if the client reports abdominal pain, as it may indicate a serious complication like pancreatitis.
Step-by-step explanation:
The question is regarding the medication exenatide, which is used in the treatment of diabetes mellitus. Among the options listed, the nurse should immediately withhold the dose of exenatide and notify the provider if the client complains of abdominal pain. This could potentially indicate pancreatitis or another severe adverse reaction which is a serious complication and requires prompt medical attention. Other symptoms like loss of appetite, muscle weakness, and heartburn, while they may be side effects worth reporting, are not typically considered immediately life-threatening in the context of exenatide use. Therefore, abdominal pain stands out as the most critical among the listed findings.