2 doctors weighed in:
What's a preservative in eye drops? Why are some eye drops preservative-free?
2 doctors weighed in

Dr. Richard Bensinger
Ophthalmology
In brief: Anti-infective
Preservatives are put in eyedrops to allow multiuse from one bottle.
The most allergenic have been removed from the market but a small industry has developed of preservative free solutions to eliminate all chance of allergy. But this requires microdropper bottles with tiny contents that have to be discarded after 1-2 uses. This is more expensive, and of dubious efficacy.

In brief: Anti-infective
Preservatives are put in eyedrops to allow multiuse from one bottle.
The most allergenic have been removed from the market but a small industry has developed of preservative free solutions to eliminate all chance of allergy. But this requires microdropper bottles with tiny contents that have to be discarded after 1-2 uses. This is more expensive, and of dubious efficacy.
Dr. Richard Bensinger
Dr. Richard Bensinger
Thank
Dr. Thomas Namey
Internal Medicine - Rheumatology
In brief: For single use !
First, some people are bothered by preservatives.
However, preservative free are always for use by one person, and should be refrigerated. Seriously, eye drops should not be shared, but those are the two reasons. Finally a third: some eye drops contain medications interfered with by the preservatives.

In brief: For single use !
First, some people are bothered by preservatives.
However, preservative free are always for use by one person, and should be refrigerated. Seriously, eye drops should not be shared, but those are the two reasons. Finally a third: some eye drops contain medications interfered with by the preservatives.
Dr. Thomas Namey
Dr. Thomas Namey
Thank
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