Final answer:
A diclofenac patch results in higher concentrations of the medication in joint tissues compared to oral medications, with a reduced risk of systemic side effects and drug interactions.
Step-by-step explanation:
The student asked how a diclofenac patch for pain from a knee injury compares to oral medications. Considering the pharmacokinetic profile of topical versus oral medication, the correct answer is (C) Concentrations in joint tissues are higher with the patch. Unlike oral medications, which must go through the digestive system and potentially interact with other drugs, a transdermal patch delivers medication directly to the affected area, resulting in higher local concentrations of the medication in the joint tissues but lower systemic blood concentrations. This localized delivery system can reduce the risk of systemic side effects and drug interactions that are more commonly seen with oral NSAIDs.