Specific Organisms and Therapeutic Regimens
Blepharitis can be classified as anterior, posterior, or marginal (combination of anterior and posterior) blepharitis.
Anterior blepharitis is generally caused by low-grade infections, primarily with Staphylococcus epidermidis or Staphylococcus aureus, but also with Propionibacterium acnes or corynebacteria.
Posterior blepharitis is generally caused by meibomian gland dysfunction or rosacea.
Marginal blepharitis can be caused by Demodex infestation or Phthirus pubis (crab lice) infestation.
Long-term daily eyelid margin hygiene is the main treatment for blepharitis, although additional pharmacological treatments may be added for each of the various types, depending on the causative organism(s).
Warm compresses/lid hygiene
A clean wet washcloth should be heated (and frequently reheated with a microwave) to 104-110°F and rested on closed eyes directly at the eyelid margin for a minimum of 10 minutes (up to 15-20 minutes in severe cases). The heat opens the meibomian gland pores and melts the clogged oils.
With the same wash cloth, scrub the base of the eyelashes to express the meibomian glands and to remove any scurf, collarettes, and crusting.
This procedure should be repeated twice a day until the blepharitis has resolved.
Anterior blepharitis - Pharmacological treatment for staphylococcal infection
Pharmacological treatments for anterior staphylococcal blepharitis include the following:
Bacitracin ophthalmic ointment applied to lid margin qid for 1-2 weeks or
Erythromycin ointment applied to lid margin qid for 1-2 weeks or
Azithromycin ophthalmic drops bid for 3 days then once daily for 27 days  or
Tobramycin 0.3%/loteprednol etabonate 0.5% ophthalmic suspension qid in each eye for 2 weeks  or
Tobramycin 0.3%/dexamethasone 0.1% ophthalmic solution qid in each eye for 2 weeks or
Avenova eyelid scrub (hypochlorous acid 0.01%, Nova Bay Pharmaceuticals) bid in each eye
Posterior blepharitis - Pharmacological treatment for meibomian gland dysfunction and rosacea
Pharmacological treatments for posterior blepharitis due to meibomian gland dysfunction and rosacea include the following:
Minocycline PO 50 mg bid for 2 months  or
Azithromycin PO 500 mg/day for 2 weeks or
Cyclosporin ophthalmic solution bid in each eye for 1 year  or
Omega 3 essential fatty acids PO 1000 mg/day
Marginal blepharitis - Pharmacological treatment for Demodex infections
Pharmacological treatments for marginal blepharitis due to Demodex infections include the following:
Tea tree oil 5% daily eyelid scrub for 6 weeks or
Cliradex eyelid wipe bid in each eye for 6 weeks