Which of the following medications is specifically indicated for both chlamydia and gonorrhea?

Azithromycin is specifically indicated for the treatment of both chlamydia and gonorrhea due to its effectiveness against the bacteria that cause these infections. It works by inhibiting bacterial protein synthesis, which ultimately leads to cell death. Azithromycin is often used in combination with other antibiotics, such as ceftriaxone, to provide a broad-spectrum approach to treating co-infections.

In contrast, the other listed medications do not have the same broad-spectrum efficacy against both pathogens. Amoxicillin is primarily effective against certain bacterial infections but is not the first-line treatment for either chlamydia or gonorrhea. Tetracycline has some activity against chlamydia but is not a standard treatment choice for gonorrhea, making it less effective for this dual purpose. Fluorouracil is an antimetabolite used mainly in cancer treatment and has no indication for treating chlamydia or gonorrhea, rendering it irrelevant for this particular clinical scenario. Hence, azithromycin stands out as the appropriate choice for both infections.