Which condition is commonly treated with tetracyclines?

• A. Meibomian gland dysfunction
• B. Chlamydial conjunctivitis
• C. Herpes simplex keratitis
• D. Bacterial keratitis

Answer: (B)

Tetracyclines are effective against intracellular bacteria, which is why they’re a classic choice for chlamydial conjunctivitis. Chlamydia lives inside conjunctival cells, and tetracyclines (like doxycycline) inhibit bacterial protein synthesis by binding the 30S ribosomal subunit, allowing them to reach and act on this intracellular organism. That makes systemic tetracyclines a standard therapy for inclusion conjunctivitis caused by Chlamydia.

While tetracyclines can be used for meibomian gland dysfunction due to anti-inflammatory effects, the common ophthalmic association tested is chlamydial conjunctivitis. Herpes simplex keratitis is a viral infection and treated with antivirals, not tetracyclines. Bacterial keratitis is typically managed with broad-spectrum topical antibiotics, with regimens chosen based on severity and risk factors rather than tetracyclines as first-line.