A client who has active tuberculosis and is taking rifampin reports that his urine and sweat have developed a red tinge. Which of the following actions should the nurse take?

Rationale for Correct Answer (C): Document this as an expected finding. Rifampin is known to cause harmless discoloration of bodily fluids like urine and sweat. This is a common side effect and does not indicate any serious issues. The nurse should document this finding to track the client's response to the medication and educate the client about it.

Summary of Incorrect Choices:
A: Checking liver function test results is not necessary for the red discoloration caused by rifampin.
B: Increasing fluid intake will not resolve the red tinge as it is a known side effect of rifampin.
D: Dialysis is not indicated for the harmless discoloration caused by rifampin.