Punctal plug

A punctal plug (tear duct plug) is a small medical device that is inserted into the tear duct (puncta) of an eye to block the duct. This prevents the drainage of liquid from the eye. They are used to treat dry eye.

Artificial tears are usually still required after punctal plug insertion.

Types

A temporary punctal occlusion can be inserted and tried first. These are made of collagen and are dissolvable. This is to ascertain that permanent ones will not cause excessive tearing.

Permanent punctal plugs are usually made of silicone. These are available in various sizes. For maximum effectiveness, the largest size that fits should be used. These are more effective than collagen plugs. They can sometimes become loose and fall out, in which case they can be replaced.

Some plugs are made of thermally reactive material. Some of these are inserted into the punctum as a liquid and then they harden and conform to the individual's drainage system. Others start out rigid and become soft and flexible, adapting to the individual's punctal size after they are inserted.