Are Methylsulfonylmethane (MSM) drops effective for treating dry eye syndrome?

MSM Drops Are Not Recommended for Dry Eye Treatment

MSM (methylsulfonylmethane) drops are not included in evidence-based treatment guidelines for dry eye syndrome and should not be used as a primary or adjunctive therapy. The most recent comprehensive guidelines from the American Academy of Ophthalmology (2024-2025) do not mention MSM as a treatment option at any stage of dry eye management 1, 2.

What You Should Use Instead

For Mild Dry Eye (First-Line Treatment)

• Start with preservative-free artificial tears containing methylcellulose or hyaluronic acid/hyaluronate at least twice daily, increasing frequency up to hourly as needed 2, 3, 4
• Switch to preservative-free formulations if using more than 4 times daily to avoid ocular surface toxicity 1, 4
• Use liquid drops for daytime, gels for longer-lasting effect, and ointments for overnight protection 2, 3

Environmental Modifications (Essential First Steps)

• Eliminate all cigarette smoke exposure, as it adversely affects the tear film lipid layer 1, 3
• Humidify ambient air and use side shields on spectacles to minimize air draft exposure 2, 3, 4
• Lower computer screens below eye level and take breaks every 20 minutes to encourage full blinking 2, 3, 4

For Moderate Dry Eye (When Artificial Tears Are Insufficient)

• Add topical cyclosporine 0.05% twice daily (12 hours apart) to prevent T-cell activation and reduce inflammation, with demonstrated success rates of 74% in mild, 72% in moderate, and 67% in severe dry eye 2, 3, 4
• Consider lifitegrast 5% ophthalmic solution which blocks LFA-1/ICAM-1 interaction to prevent T-cell activation 2
• Use short-term topical corticosteroids (2-4 weeks maximum) for acute exacerbations, but monitor for increased intraocular pressure and cataracts 2, 3, 4

For Evaporative Dry Eye (Meibomian Gland Dysfunction)

• Treat underlying meibomian gland dysfunction with warm compresses and lid massage 2, 5
• Use lipid-containing artificial tears specifically for patients with meibomian gland dysfunction 2, 3
• Consider perfluorohexyloctane (Miebo) for direct evaporation control, with improvements seen as early as 2 weeks 2

Advanced Treatments for Severe Dry Eye

• Punctal plugs or punctal cautery for tear retention after optimizing topical therapy 2, 3, 4
• Autologous serum eye drops improve ocular irritation and corneal staining, particularly beneficial in Sjögren's syndrome 2, 3, 4
• Varenicline nasal spray stimulates tear production via trigeminal nerve stimulation for patients with inadequate response to traditional drops 2, 4
• Oral secretagogues (pilocarpine 5mg four times daily or cevimeline) for patients with Sjögren's syndrome 2, 3, 4

Critical Pitfalls to Avoid

• Do not use preserved artificial tears more than 4 times daily as they cause ocular surface toxicity 1, 4
• Do not delay anti-inflammatory therapy if symptoms persist after 2-4 weeks of optimized artificial tear use 4
• Never use topical corticosteroids beyond 2-4 weeks due to risk of infections, increased intraocular pressure, and cataract formation 2, 3, 4
• Do not ignore concurrent blepharitis or meibomian gland dysfunction as treating lid margin disease with warm compresses and lid hygiene is essential for treatment success 1, 4

Why MSM Is Not Recommended

The comprehensive 2024 American Academy of Ophthalmology Dry Eye Syndrome Preferred Practice Pattern and 2025 treatment guidelines provide a stepwise algorithm for dry eye management that includes artificial tears, anti-inflammatory agents (cyclosporine, lifitegrast), corticosteroids, punctal occlusion, autologous serum, and various advanced therapies 1, 2. MSM drops are conspicuously absent from all evidence-based treatment algorithms. A systematic review of over-the-counter artificial tears found that most formulations have comparable efficacies, but MSM was not among the studied formulations 6. Without clinical trial evidence demonstrating safety and efficacy for dry eye, MSM drops cannot be recommended over proven therapies.