The purpose of this study is to evaluate the drug concentrations of AzaSite compared to Vigamox in tears of healthy volunteers

Inclusion Criteria:

• Have visual acuity, using corrective lenses (no contact lenses) if necessary, in both eyes of at least +0.7 as assessed by Early Treatment of Diabetic Retinopathy Study.
• Have normal lid anatomy.

Exclusion Criteria:

• Have an abnormal biomicroscopy or ophthalmoscopy exam.
• Have a diagnosis of dry eye disease or have experienced any of the dry eye symptoms (photophobia, foreign body sensation, itching, burning, pain, dry or grittiness) in the past thirty days.
• Have used artificial tears in the past thirty days.
• Have a diagnosis of on-going ocular infection or lid margin inflammation.
• Have ever had penetrating ocular surface or intraocular surgery.
• Have a known hypersensitivity to azithromycin, or any macrolide antibiotic or to any of the ingredients in AzaSite.
• Have had a known hypersensitivity to Vigamox or any fluoroquinolone antibiotics or to any of the ingredients in Vigamox.
• Have had corneal or lid abnormalities.
• Have glaucoma, or Intra Ocular Pressure of 22 mm Hg or greater in one or both eyes.
• Have any ocular pathology with the exception of cataracts.
• Have a serious systemic disease or uncontrolled medical condition.
• Have experienced symptoms of viral or allergic conjunctivitis in the past 30 days.
• Have a history of liver or kidney disease resulting in persisting dysfunction.