DEC 2025
When symptoms overlap with other eye conditions, Demodex blepharitis is often missed.1,2 Our new video walks through a fast, exam-room technique: collarettes are the pathognomonic sign of Demodex mite overgrowth, identified using a slit lamp with patients looking down (10-16x).1,3 Global data show high prevalence in eye care patients (58% US4*, 54% Europe5†, 66% Japan6‡).
0:05 – You know this patient well.
0:07 – Red, itchy, irritated eyes that just won’t resolve.
0:10 – The symptoms may improve for a while after treatment, but they always come back again and again.
0:16 – You see them repeatedly, and you sense the growing frustration.
0:20 – Theirs, and perhaps yours, too.
0:22 – Demodex mites are a natural part of the skin’s microbiome.
0:25 – But when their population expands deep in the lash follicle, they can become pathogenic, triggering chronic inflammation at the lid margin.
0:33 – And often this overgrowth remains hidden just beneath the surface.
0:37 – This is a global issue.
0:39 – In the United States, one study found that 58% of patients who visited an eye care clinic had Demodex blepharitis, regardless of their initial reason for the visit.
0:48 – In Japan, that number climbs to 66%, and across Europe, experts observe it in 54% of their patients.
0:57 – The conclusion is clear.
0:59 – While Demodex mites are ubiquitous and typically present in small numbers, over half the people across these regions show evidence of overgrowth, far more than most patients or even clinicians might expect.
1:11 – Despite this high prevalence, such cases often go undiagnosed.
1:16 – Dr Radhika Rampat: ‘When you hear that nearly six in ten patients have Demodex blepharitis, it sounds high until you start to routinely examine the lid margin.
1:24 – Once I made it a part of my anterior segment workflow, I realised how many of my so-called refractory cases, patients who didn’t improve despite multiple therapies, were actually driven by Demodex.
1:36 – It’s easy to miss because the symptoms overlap with so many other conditions, but the consequences are real.
1:42 – The patients stay stuck in cycles of discomfort, and we waste time chasing the wrong diagnosis.
1:48 – Spotting it early changes the conversation.
1:51 – It brings clarity to the exam and to the patient.’
1:54 – So is Demodex blepharitis underestimated in your practice?
1:58 – The answer isn’t a complex test.
2:00 – You don’t need any new, expensive equipment.
2:03 – It’s pathognomonic sign, the Collarette.
2:06 – These distinct waxy sleeves at the base of the lashes are definitive evidence of mite overpopulation.
2:12 – The presence of Collarettes confirm Demodex blepharitis.
2:16 – Forget about plucking lashes and examining them under a microscope.
2:20 – Everything you need to make this diagnosis is already part of your exam room.
2:23 – Your slit lamp.
2:25 – It adds no extra time to your routine.
2:27 – Simply ask the patient to look down.
2:29 – Set your magnification between 10X and 16X and focus on the upper lash line.
2:35 – Incorporate the look down method into your standard routine.
2:47 – Scan the code to join the Collarette Community and get the latest updates on Demodex Blepharitis Education.
GL--2500139 12/25
* US: A retrospective chart review for DB by 7 investigators at 6 eye care clinics of the case records of patients (N=1032) who underwent a slit lamp examination, regardless of chief complaint.4
† EU: Data from an evaluation of 804 patients from 6 countries in Europe, including 15 clinicians each with ~50 consecutive patients.5
‡ Japan: An observational, cross-sectional (single visit) study of 349 patients from 10 sites in Japan.6
1. Fromstein SR, Harthan JS, Patel J, Opitz DL. Demodex blepharitis: clinical perspectives. Clin Optom (Auckl). 2018;10:57-63. 2. Ocular allergies. American Optometric Association. Accessed September 14, 2022. https://www.aoa.org/healthy-eyes/eye-and-vision-conditions/ocular-allergies?sso=y. 3. Sharma N, Martin E, Pearce EI, et al. A Delphi approach to establihsing a consensus on best practice for the diagnosis and treatment of Demodex blepharitis. Cont Lens Anterior Eye. 2024;47(1):102080. 4. Trattler W, Karpecki P, Rapoport Y, et al. The prevalence of Demodex blepharitis in US eye care clinic patients as determined by collarettes: a pathognomonic sign. Clin Ophthalmol. 2022;16:1153-1164. 5. Tarsus Data on File. 6. Chikama T, et al. The prevalence and symptomology of demodex blepharitis in Japan: The Elara study. Invest Ophthalmol Vis Sci. 2025;66:4500.