Are preservative-free eye drops worth it?

Preservative-free eye drops are worth it mainly for people who use drops several times a day and would rather keep a preservative out of what goes in their eyes. The trade-offs are more careful handling, attention to storage and sometimes a higher price per use. Whether that’s worth it for you depends on how often you use drops, and your eye doctor can weigh in on your situation.

What do preservative-free eye drops do?

They do the same job as any lubricating drop with the same kind of active ingredients. “Preservative-free” describes what’s missing from the formula, not an extra effect. A preservative is added to multi-use solutions to keep microbes from growing once the bottle is open. Leaving it out doesn’t change what the label’s Uses say the drop is for. In Quell’s case, those Uses are For use as a protectant against further irritation or to relieve dryness of the eye, and its active ingredients are Glycerol (1.0%), Polysorbate 80 (1.0%) and Light Mineral Oil (0.5%).

If you want to read more about what a preservative is and how to find one on a label, see what preservative-free means.

Who tends to look for them

• People who use drops on a schedule every day rather than once in a while, because the number of times an ingredient touches the eye adds up.
• People who have noticed that a particular drop stings or bothers them and want to compare formulas.
• People whose eye doctor has told them to choose a preservative-free product.
• Shoppers who read inactive ingredient lists closely and prefer shorter or simpler ones.

None of those reasons makes one kind of drop right for everyone. Someone who uses a drop twice a month during allergy season has a different calculation from someone following Quell’s directions, which read Apply 1 drop 3 times per day in each eye. At that rate, a bottle is in daily use for weeks.

Preservative free eye drops vs regular

Comparing the two fairly means looking at more than one word on the front of the box:

• Active ingredients: if two drops share the same kinds of actives, they’re aiming at similar uses, preservative or not.
• Inactive ingredients: a preservative would appear here. Quell lists 10 inactive ingredients and none of them is a preservative.
• Package: preservative-free drops come either in single-use vials meant to be thrown away after one use, or in multi-dose bottles like Quell’s.
• Handling: without a preservative, keeping the bottle clean depends more on you.
• Price per use, including shipping.

What preservative-free means in a multi-dose bottle

A multi-dose bottle is opened, used and recapped many times. FDA’s rule for over-the-counter eye products, 21 CFR part 349, requires multi-use containers to carry a warning against touching the tip to any surface and to tell you to replace the cap after use. Quell’s version of the tip warning reads: Do not touch tip of bottle to any surface to avoid contamination. With no preservative in the formula, that instruction is the main line of defense, so it’s worth building a routine around it:

• Wash and dry your hands first.
• Hold the bottle so the tip points down and stays clear of your lashes, eyelid and fingers.
• Cap it as soon as you’re done, and never set it down uncapped.
• Use your own bottle only; don’t share it, even within a household.

How to store preservative free eye drops

Follow the label, not a general rule of thumb. Quell’s storage line is Store between 15° to 30°C (59° to 86°F). That’s ordinary room temperature, so a bathroom drawer, nightstand or desk works. Avoid a hot car, a sunny windowsill and a freezing glove box. Before each use, a quick look at the bottle tells you whether anything has changed: The eye drops have a naturally milky-brown appearance. This is normal and does not indicate a problem with the product. The label also lists one Do not use condition: If this product changes color. Our guide on how to store eye drops has more on spots to avoid.

Comparing the cost per use

Prices on single bottles can mislead, because sizes, directions and shipping all differ. A fairer number is what you pay per day of use:

• Add the bottle price to your share of shipping. Here, shipping is $10.00 per order, and an order of 3 bottles ships free.
• Estimate how many days a bottle lasts you at the label’s directions; how long a bottle lasts explains how to work it out.
• Divide the first number by the second.
• Do the same for any drop you’re comparing, using its own size and directions.

Single-use vials usually involve opening a new one each time, which can change the math considerably. A multi-dose preservative-free bottle can sit between the two. There’s no universal answer; it depends on the products and how you use them.

What it doesn’t promise

Preservative-free is a description of a formula, not a promise about how your eyes will feel. A drop without a preservative can still contain an ingredient you react to; Quell’s label, for example, warns: Caution should be used in those with egg or bird allergies — For use in the eyes only. And no drop is a substitute for an exam when symptoms don’t settle. Stop use and ask a doctor if you feel eye pain or changes in your vision, if irritation or redness continues, or if the condition worsens or persists for 72 hours.

If you want a professional view on whether preservative-free makes sense for you, your eye doctor or pharmacist is the right person to ask, and questions to ask your eye doctor can help you prepare.