What notable effect does long-term therapy with rifampin (Rifadin) cause?

Long-term therapy with rifampin is known to cause orange discoloration of bodily fluids, including sweat, tears, urine, and feces. This effect is due to the drug's chemical properties and is a common side effect that patients should be made aware of when starting treatment. Recognizing this effect is essential for patient education, as it helps to prevent unnecessary concern about these changes, which are harmless and simply a result of the drug's metabolism and excretion.

The other choices provided do not accurately represent notable effects associated with rifampin. For instance, the idea that rifampin should always be taken with food or antacids is not a requirement; while taking it with food may help to manage gastrointestinal side effects in some patients, it is not universally necessary. Additionally, if a dose of rifampin is forgotten, doubling the next dose is not advisable; patients are usually instructed to take their next dose at the scheduled time and not to double up. Lastly, the notion that rifampin may be discontinued independently after three months if symptoms are gone is incorrect, as it is essential for patients to complete the full course of therapy to ensure effective treatment of the infection and to prevent the development of drug resistance.