Final answer:
When a patient with type I diabetes mellitus is prescribed phenytoin, an increase in their insulin dosage may be required to counteract the hyperglycemic effects of the medication and maintain blood glucose levels.
Step-by-step explanation:
A client with type I diabetes mellitus has been prescribed phenytoin (Dilantin). Based on the client's medical history, which should the nurse anticipate to be included in the treatment plan? The correct answer is d. An increase the patient's insulin.
Phenytoin is known to cause hyperglycemia as one of its side effects by increasing the levels of glucose in the blood. In patients with diabetes mellitus, this can counteract the effects of insulin, making the existing insulin less effective. Therefore, it may be necessary to adjust the insulin dosage upwards to compensate for the impact of phenytoin and maintain blood glucose levels within the target range. Continuous monitoring of blood glucose levels will be required to ensure that the correct balance of insulin is maintained and to prevent potential complications associated with hyperglycemia.
While other considerations such as a), b), and c) might have their relevance in various clinical scenarios, with respect to the interaction between phenytoin and diabetes mellitus, adjusting the insulin dosage is key.