Eye drop instillation: What’s the big deal?

What’s the big deal? Ask Monica how much tough time Rachel gave her (in Friends).

Think about the people with chronic diseases like glaucoma, who require multiple medications.

Here is the correct way for instilling eye drops, trust me.

^·          Wash both hands prior to instillation, sit down on a chair or lie on a bed. If seated, the head is tilted slightly backwards while gazing upward.

^·          The lower lid is gently pulled down with the nondominant hand to form a small concavity in which the drops will be placed. With dominant hand, the dispenser is held above this concavity. The bottle should be near enough to make sure that the drop will enter the eye and far enough so as not to touch it (2-5 cm).

^·          Avoiding blinking, the body of the bottle is pressed so that a single drop falls into the eye.

^·          After application, lids should be kept closed (or digital compression be applied to the punctum) for 1-2 minutes to minimize systemic absorption.

^·          The bottle cap should be replaced and any excess fluid wiped from the skin, especially when using prostaglandin medications that may darken the skin colour.

^·          When the eyedrop is a suspension, shake the bottle before administration.

^·          Wait at least 5 minutes between instillation of two different eyedrops.

For people with limited field, who cannot see the tip of the bottle:

Ritch Sussman technique:

·         Hold the bottle between thumb and index finger of your dominant hand.

·         Place the index finger of the other hand in the centre of lower eyelid to hold it open; point it towards the eye creating a right angle with the knuckle closest to your finger tip.

·         Place the first knuckle of your right thumb on the left index finger, point the bottle down and stop it at the knuckle of left finger.

Practical points regarding topical medications:

·         The human tear volume is approximately 7µl with a turnover rate of approximately 1 µl per minute.The use of topical drugs in the eyes doubles this rate.

·         The spontaneous tear flow will cause complete washout of medication from conjunctiva sac within 5 minutes.

·         The volume of an eye drop is 30 µl to 50 µl. Once a drop has been instilled into the eye, only 20% manages to enter the eye, will the rest either runs down the cheek or is drained through nasolacrimal duct.

·         A substantial systemic absorption takes place through highly vascularised nasal mucosa.

Hope this helps save you from the wastage and frustration due to “runny drops over the cheeks”.

Happy drop instillation.