I found this from the pinned thread.
Quoted from American Academy of Dermatology(AAD)
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Rosacea Treatment-Bumps and Pus-filled Lesions -from AAD
Non-antibiotic Dosage Doxycycline
Weighing in at only 40 milligrams of doxycycline per capsule, this dosage of doxycycline is not potent enough to kill bacteria. Since it cannot kill bacteria, it does not act as an antibiotic.
Effectiveness: Research shows that 40 milligrams can effectively stop inflammation. When inflammation decreases, patients tend to see fewer bumps and pus-filled lesions.
In clinical trials, this medication has proven safe and effective for treating the bumps, pus-filled lesions, and redness of rosacea. This led the U.S. Food and Drug Administration (FDA) to approve non-antibiotic dosage doxycycline for the treatment of the bumps and pus-filled lesions of rosacea in adults. The medication is meant for once daily use and can be taken long term.
Side Effects: While the antibiotic dosage of doxycycline can cause side effects, these side effects were not observed in the clinical trials for non-antibiotic dosage. Patients did not say they had an upset stomach or sun sensitivity. None of the women treated with the non-antibiotic dosage, also called the anti-inflammatory dosage, experienced a yeast infection. Since the anti-inflammatory dosage cannot kill bacteria, a patient would not be expected to develop antibiotic resistance. When a patient develops antibiotic resistance, the antibiotic becomes ineffective in killing or weakening the targeted bacteria. Antibiotic resistance is a global health concern.
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Advances Changing Face of Rosacea Treatment -from AAD
Non-antibiotic Doxycycline Treats Bumps and Pus-Filled Lesions
Weighing in at only 40 milligrams of doxycycline per capsule, this dosage of doxycycline is not potent enough to kill bacteria. Since it cannot kill bacteria, it does not act as an antibiotic. But research shows that 40 milligrams can effectively stop inflammation. When inflammation decreases, patients see fewer bumps and pus-filled lesions.
This result was seen again and again during clinical trials. In the phase III clinical trials the final trials needed to determine whether or not a drug will receive approval from the U.S. Food and Drug Administration (FDA) adults with moderate to severe rosacea were asked to take one capsule per day for 16 weeks. The capsule contained either 40 milligrams of doxycycline or a placebo (no active ingredient).
The adults who received the 40 milligrams of doxycycline saw significantly greater improvement. On average, each person in the study had about 20 bumps and/or pus-filled lesions and 2 or fewer nodules. The adults who received the 40 milligrams of doxycycline saw between 11.8 and 9.5 fewer lesions by week 16. This translates to a mean reduction of 61% and 46%, respectively. Adults who received the 40 milligrams of doxycycline also saw a significant decrease in facial redness.
When the patients were also given 1% metronidazole gel, a medication approved by the FDA for treating the papules and pustules of rosacea, the lesions decreased more quickly. The gel was to be used daily for 12 weeks and then stopped. The patients continued taking the 40 milligrams of doxycycline for 16 weeks.
While the antibiotic dosage of doxycycline can cause significant side effects, such side effects were not reported in these clinical trials. Patients did not say they had an upset stomach or sun sensitivity. None of the women treated with the non-antibiotic dosage, also called the anti-inflammatory dosage, experienced a yeast infection. Since the anti-inflammatory dosage cannot kill bacteria, a patient would not be expected to develop antibiotic resistance. When a patient develops antibiotic resistance, the antibiotic becomes ineffective in killing the targeted bacteria. Antibiotic resistance is a global health concern.
The results of these studies led the FDA to approve the 40-milligram capsule of doxycycline for the treatment of the papules (bumps) and pustules (pus-filled lesions) of rosacea in patients who are 18 years of age and older. This 40-milligram capsule is approved for once daily use.