ASK DIS: Eye Drops vs Ear Drops

One reason for this is that eye drops must be sterile. Some ear drops are sterile (e.g., Ciprodex, Floxin Otic [U.S.], etc), but some are not (e.g., Cipro HC [U.S.], etc).
Plus, eye tissue is much more sensitive than ear tissue.
Ear drops are generally more acidic than eye drops, and can be irritating to the eyes
eye drops can’t automatically be substituted for ear drops to help patients save money. Eye drops must be specifically indicated on the prescription
There are reports of errors where ear drops have been administered into patients’ eyes. Putting these products in the eyes can cause redness and swelling of the eyes, and blurred vision.
Flushing the eyes with water or saline, and a visit to the emergency department or ophthalmology clinic might be required

Storage

Most eye drops and ear drops can be stored at room temperature. However, there are a few commonly used eye drops that do require refrigeration.
Both Azasite (azithromycin, U.S. only) eye drops and Xalatan (latanoprost) eye drops should be stored in the refrigerator. Remember this when you are locating the product in the pharmacy to dispense.
Fortunately, these products can be left at room temperature for a number of days (six weeks for Xalatan and 14 days for Azasite) after they are dispensed to patients.
Proparacaine (Alcaine, etc) eye drops also need to be refrigerated. Plus patients need to refrigerate proparacaine eye drops once they are dispensed. Make sure to affix an auxiliary label to indicate this if you dispense proparacaine eye drops.
Proparacaine isn’t likely to be dispensed commonly in outpatient settings.
To prevent mix-ups between eye drops and ear drops, it’s a good idea to store these products in separate places in the pharmacy, or use shelf tags.

How to Supply

most common conversion for drops to mL is 20 drops/mL.
However, some insurance companies or employers might require you to use a conversion of 15 or 16 drops/mL.

Reference:

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