It is a pilot study aimed to determine if oral Mucinex® is effective in reducing the amount of corneal filaments and improving symptomology in subjects with filamentary keratitis.

The study is aimed to determine if oral administration of Mucinex® is effective in reducing the amount of corneal filaments and improving symptomology in subjects with filamentary keratitis. Subjects will be instructed to take 600 mg tablets of extended release Mucinex® twice a day (total dose is 1.2 g/day) for 4 weeks.

Inclusion Criteria:

• Patients with filamentary keratitis
• 18 years and older

Exclusion Criteria:

• Active ocular surface infection of any type
• Recent ocular surgery (<30 days) history of nephrolithiasis as Mucinex® has been associated in rare cases of development of kidney stones
• Schirmer's test<3mm
• History of hypersensitivity to Mucinex®
• Concurrent eye disease requiring immediate initiation of a new treatment (e.g. topical steroids) restriction for water intake can exacerbate the risk of nephrolithiasis.

All the subjects received Mucinex

From study start following enrollment to study completion (4 weeks).

All the subjects once enrolled into study were followed till they completed their week 4 follow-up visit and were asked about any AE. The PI's contact information was listed on ICF for the subjects to call in course of any AE.