Final answer:
When a patient takes warfarin and carbamazepine together, the nurse would anticipate an order to increase the dose of warfarin, perform more frequent aPTT monitoring, and not provide extra dietary vitamin K.
Step-by-step explanation:
When a patient takes warfarin and carbamazepine together, there is a potential for drug-drug interactions. Carbamazepine can increase the metabolism of warfarin, leading to a decrease in its effectiveness. As a result, the nurse would anticipate an order to increase the dose of warfarin to maintain therapeutic anticoagulation. This adjustment is necessary because carbamazepine can speed up the breakdown of warfarin in the liver.
In addition, the nurse would also expect more frequent aPTT monitoring to assess the patient's clotting time and adjust the warfarin dose accordingly. aPTT (activated partial thromboplastin time) is a blood test used to measure how long it takes for blood to clot.
Providing extra dietary vitamin K is not necessary in this case because carbamazepine does not interact with vitamin K. Warfarin works by inhibiting the synthesis of vitamin K-dependent clotting factors, so supplying additional vitamin K would counteract the effect of warfarin.