Hello, thanks for using HCM. It is most likely that you are suffering from an allergic conjunctivitis. Allergic conjunctivitis could be seasonal to environmental allergens (pollen) or perennial (due to household allergens like mould, cosmetics, pet hair etc) and most often occurs in people with a history of asthma or atopic dermatitis in their family. Treatment relies on avoiding allergens and on the use of antihistamines. Allergic conjunctivitis is due to allergy and tetracycline being an antibiotic is not indicated unless there is a bacterial infection which will manifest by purulent ocular discharges. Other possible causes of the itch: dry eye syndrome in which insufficient tear is produce with treatment requiring artificial tears and atopic dermatitis which present with itch on the skin. Another possible cause is atopic keratoconjunctivitis which has a higher probability of having infectious complications especially to herpes and thus requires more attention and follow up. In as much as itchy eyes sounds more or less simple or not invalidating, it is necessary to visit an ophthalmologist for a better examinaiton, follow up and eventual pieces of advice. Best regards and hope this helps.