Hello. Thanks for writing to us at healthcaremagic. Your concern is absolutely genuine. Acne can recur once the patient is taken completely off all treatments. However, since Doxycycline (Microdox) is an oral antibiotic and cannot be continued forever, therefore, what most dermatologist do is that once acne activity in under good control; they would ask the patient to continue topical treatment with a maintenance gel, commonly a topical retinoid e.g Adapalene Or tretinoin. Topical retinoids are comedolytic, anti-inflammatory and thus prevent new acne from reforming. Therefore regular use of topical retinoids is adequate to sustain the improvement. I would suggest that you discuss about this concern with your dermatologist. You dermatologist will tell you more about maintenance treatment with a topical retinoid and surely would prescribe one. Regards