Doxycycline is already being used clinically and is in place in the management of chronic meibomian gland dysfunction associated dry eye disease including the below mentioned guidelines.

Indian Guideline: If chronic symptoms and signs  of MGD are not adequately controlled by eyelid cleansing or meibomian gland expression, daily oral doxycycline, minocycline, or tetracycline may be helpful and tapered when clinical improvement is documented. [Guideline name: Evaporative dry eye disease due to meibomian gland dysfunction: Preferred practice pattern guidelines for diagnosis and treatment. Indian J Ophthalmol 2023;71:1348-56].

International workshop on meibomian gland dysfunction: report of the subcommittee on management and treatment of meibomian gland dysfunction:

Systemic tetracycline derivatives (e.g., tetracycline 250 mg four times per day or doxycycline 100 mg two times per day) for 6 weeks to several months in recurrent cases,

Recommendations in Clinical Handbooks for Treatment of Posterior Blepharitis and Meibomitis:

Moorfields Manual: With corneal involvement: Doxycycline 100 mg once a day or Erythromycin 250 mg four times a day for 8 weeks.

Wills Eye Manual: Tetracycline 250 mg four times a day or doxycycline 100 mg twice a day for 6 weeks.

Japan: Oral administration of azithromycin and tetracycline antimicrobials (doxycycline and minocycline) is effective in improving subjective symptoms and meibomian gland orifice/surrounding findings in patients with MGD.

This is to be noted that patients are already getting Doxycycline 100 mg BD (the high dose mentioned in our study) as per different guideline recommendations. However, single low sample RCT has showed that efficacy is similar in both the cases (high dose and low dose of doxycycline), however adverse effects were quite lower with the lower dose compared to the traditionally used higher dose.

Given the potential side effects associated with traditional higher doses of Doxycycline (100 mg BD), such as gastrointestinal disturbances, this current study aims to fill the gap by directly comparing low and high doses of Doxycycline, to evaluate their relative efficacies and safety profiles in managing chronic MGD.