Ophthalmic Drops

Liquid medicines and lubricants formulated for the eye

Overview

Ophthalmic drops are liquid medicines formulated for application to the surface of the eye and are the most common way of delivering drugs to the eye. They include lubricants, or artificial tears, based on polymers such as carboxymethylcellulose, hyaluronic acid, and polyethylene glycol, along with gels and ointments that stay in contact longer. Medicated drops span many drug classes, including antibiotics, antivirals, antihistamines and mast cell stabilizers for allergy, corticosteroids and nonsteroidal anti inflammatory drugs, and glaucoma medications such as prostaglandin analogs like latanoprost, beta blockers like timolol, alpha agonists like brimonidine, and carbonic anhydrase inhibitors. Diagnostic drops include dilating agents, anesthetics, and fluorescein dye. Only a small fraction of a drop penetrates into the eye, as most drains through the tear ducts or spills away, and some is absorbed into the bloodstream through the nasal lining, which explains why some eye drops, such as beta blockers, can have systemic side effects. Multi dose bottles usually contain preservatives such as benzalkonium chloride, which can irritate the ocular surface with long term frequent use, prompting the development of preservative free formulations. Vasoconstrictor drops for redness are associated with rebound redness when used regularly.