Demodex mites are linked to some inflammatory diseases like rosacea and blepharitis and could be harmful in patients with immunodeficiency or immunosuppression, especially in patients using biologics like dupilumab. The present study evaluated different anti-Demodex strategies based on interventional clinical evidence with quantified Demodex mite data. It used PubMed, Embase, ClinicalTrials.gov, Medline and the International Clinical Trials Registry Platform (ICTRP) as databases and assessed the risk of bias using the RoB2 and ROBINS-I tools. The study assessed the certainty of evidence following the GRADE guideline and compared the effect sizes (ESs) of different strategies in different periods (0-1, 1-2, 2-3, >3 months), as well as Demodex decrease rates. 

The study observed:

• Identification of 1,618 studies in the databases, among which 21 were included in the final quantitative synthesis. 
• Studies revealed interventions like ivermectin, tea tree oil (TTO), permethrin, crotamiton, metronidazole, light therapies, combined therapies and other therapies. 
• During 0 to 1 month, the variation in ES ranged from 0.07 (cleanser) to 1.95 (systemic ivermectin-metronidazole). 
• During 1 to 2 months, the variation in ES ranged from 0.88 (topical permethrin) to 4.40 (topical ivermectin). 
• During 2 to 3 months, the variation in ES ranged from 0.79 (topical permethrin) to 8.37 (topical ivermectin). 
• During the time of 3 months, the variation in ES ranged from 0.59 (topical permethrin) to 2.25 (intense pulsed light [IPL]). 
• Regarding Demodex decrease rates, topical ivermectin, TTO, permethrin, IPL and baby shampoo achieved a nearly 100% decrease. 
•  Mostly mild and none severe adverse events in the studies.

This study regards ivermectin (topical and systemic), ivermectin-metronidazole (topical) and TTO (topical) are promising anti-Demodex interventions. Along with traditional pharmacotherapy, light therapies, especially IPL and skin cleansing, could also effectively control Demodex mite infestation.

Source: Li J, Wei E, Reisinger A, et al. Comparison of different anti-Demodex strategies: a systematic review and meta-analysis. Dermatology. 2023;239(1):12-31.