The pathogenesis of rosacea is still unclear, and current treatments are all symptomatic; nevertheless, the treatment options for the condition are still being broadened. The safety, efficacy, optimal dose and duration of treatment of various drugs are still inconclusive and will be discussed in this article.
Typology and Classification of Rosacea
Typing.
Type I: Erythematous capillary dilatation type
The most common type is erythema with capillary dilation, which is temporary or persistent.
Type II: Papulopustular type
Temporary papules and/or pustules appear on top of persistent facial erythema, and this type may have burning and stinging sensation.
Type III: Mass type
Thickening of the skin, irregular nodular hyperplasia (e.g. rosacea), enlarged hair follicles and dilated capillaries are seen in the lesion area.
Type IV: Eye type
Dry, burning, itchy eyes. The conjunctiva is congested and edematous, preferably in whites.
Grading.
None, Mild, Moderate, Severe (0-3)
Treatment strategies.
Different treatment measures are available for different subtypes.
Type I: the most difficult to treat and can be treated symptomatically with isotretinoin and pulsed dye laser.
Type II: the easiest to treat and can be treated with topical or oral isotretinoin or antibiotics.
Type III: General surgery or laser treatment, isotretinoin can delay the onset of rosacea.
Type IV: Mild cases can be treated with eye hygiene and topical medication, and severe cases can be treated with oral antibiotics.
Drug treatment
Topical medications.
Three FDA-approved topical applications for rosacea are: 0.75% and 1% metronidazole, 10% sodium salt and 5% sulfur ration, 15% azelaic acid
1. Metronidazole: A study of 582 patients with papulopustular rosacea showed that topical 0.75% metronidazole was effective and well tolerated twice daily, with nearly 50% of the erythema subsiding after 12 weeks. Side effects were minimal and generally consisted of pruritus, dryness and mild irritation of the skin. The efficacy of the various dosage forms, 0.75% and 1% metronidazole, is similar, with the gel being the best tolerated. Some studies have shown that once-daily 1% metronidazole gel and twice-daily 15% azelaic acid are similar in efficacy, with the former being better tolerated.
2, 10% sodium salt and 5% sulfur ratio: a study showed that the use of 8 weeks, inflammatory lesions reduced 78%, erythema reduced 83%, well tolerated. The new sodium sulfacetamide gel has less residual odor, low irritation, very little interaction with other drugs, and better efficacy when used in combination with metronidazole.
3, 15% azelaic acid: there are 15% gel and 20% cream two, is a natural saturated dihydroxy acid. With erythema and inflammatory lesions have a certain effect.
Other topical drugs.
1, tacrolimus: 0.1% and 0.075% tacrolimus ointment has some efficacy on inflammatory rosacea due to its mechanism of inhibiting T-cell activation and cytokine release. Experiments have confirmed that topical application of tacrolimus ointment twice daily combined with oral administration of 100 mg minocycline twice daily can clear most of the inflammatory lesions within 1-2 months.
2, retinoic acid: there are few reports on this drug, there are reports that 0.025% retinoic acid to reduce erythema and eliminate capillary dilation. However, the onset of action is very slow, usually after 2 months.
Oral drugs.
1, tetracyclines: the general dose of tetracycline 250-1000mg/day, doxycycline 40mg/day (100-200mg/day in the past as an anti-microbial dose), minocycline 100-200mg/day, the use of 3-4 weeks rosacea inflammatory skin lesions were substantially improved. Recent studies have shown that rosacea is a non-infectious skin disease and that tetracycline antibiotics are still effective in this disease because of their immunosuppressive and angiogenic inhibitory properties.
Second generation tetracyclines including minocycline have high bioavailability, long half-life and low gastrointestinal reactions compared to first generation tetracyclines. Studies have shown that 40mg/dose/day of doxycycline extended release capsule, for patients not only good efficacy, improve compliance, and reduce the occurrence of drug resistance.
2.Macrolides: Erythromycin is not used much because of severe gastrointestinal reactions. Second-generation macrolide antibiotics (such as azithromycin and clarithromycin) have mild gastrointestinal reactions, and one study showed that after 12 weeks of administration, the overall score of rosacea decreased by 75% and the inflammatory lesions subsided by 89%.
3. Isotretinoin: Small studies have shown that it can reduce skin blood flow and is effective in improving inflammatory skin, erythema, and capillary dilation in rosacea. However, further research is needed to confirm and compare its efficacy.
4. Metronidazole: Studies have shown that metronidazole 200 mg orally twice daily and tetracycline 250 mg orally twice daily for 6-12 weeks have similar efficacy. However, metronidazole may induce seizures and other neurological pathologies when taken orally, so care should be taken, and alcohol should be abstained from during administration.