A nurse is reviewing the medical records for a group of clients prior to administering the clients' medications. For which of the following clients should the nurse withhold the prescribed medication and notify the provider?

A. Venlafaxine and frequent yawning/weight loss: Frequent yawning and weight loss are not typical signs of an adverse reaction to venlafaxine. These symptoms can occur with various conditions, but they do not necessarily require withholding the medication. B. Olanzapine and frequent urination: Frequent urination is not a known side effect of olanzapine. However, the nurse should assess the client for other factors contributing to this symptom. It may not be severe enough to require withholding the medication without further evaluation. C. Fluoxetine and muscle rigidity/tachycardia: Muscle rigidity and tachycardia could indicate serotonin syndrome, a potentially life-threatening condition. This requires immediate intervention, and the medication should be withheld while notifying the provider for further evaluation and treatment. D. Nortriptyline and nausea/dry mouth: Nausea and dry mouth are common side effects of tricyclic antidepressants like nortriptyline. These symptoms typically do not require withholding the medication, but the nurse should monitor the client for any worsening or additional adverse effects.