Final answer:
The nurse suspects that the client is experiencing neuroleptic malignant syndrome (NMS), which is a potentially life-threatening condition that can occur as a side effect of antipsychotic medications. It is characterized by fever, altered mental status, muscle stiffness, and other systemic symptoms.
Step-by-step explanation:
The nurse suspects that the client is experiencing neuroleptic malignant syndrome (NMS). Neuroleptic malignant syndrome is a potentially life-threatening condition that can occur as a side effect of antipsychotic medications, such as risperidone. It is characterized by a combination of fever, altered mental status, muscle stiffness, autonomic dysregulation, and other systemic symptoms.
In this case, the client's symptoms of high fever, muscle stiffness and pain, excessive sweating and salivation, and changes in mental status are consistent with NMS. The nurse should notify the healthcare provider immediately because NMS requires prompt medical intervention, including discontinuation of the antipsychotic medication and supportive care.