People with rosacea first took low-dose doxycycline openly for 12 weeks. Those who did well were then randomly assigned to keep taking it or switch to placebo for a further 40 weeks, without knowing which they got. By the end, 13.8% on the drug had relapsed versus 27.7% on placebo. The randomized, blinded part is the trustworthy part; note it only included people who had already responded, so this speaks to staying clear, not to getting clear. Manufacturer-funded.
Del Rosso JQ, Brantman S, Baldwin H. Long-term inflammatory rosacea management with subantibiotic dose oral doxycycline 40 mg modified-release capsules once daily. Dermatol Ther. 2022;35(1):e15180.
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