Artificial tears are over-the-counter eye drops designed to supplement or replace your natural tear film when your eyes aren’t producing enough moisture on their own. They’re the most common first-line treatment for dry eye disease, but millions of people also use them for temporary relief from irritation caused by screens, wind, allergies, or contact lenses. With dozens of products on the shelf, understanding what’s actually in these drops and which type suits your situation can save you a lot of trial and error.
How They Work
Your natural tear film isn’t just water. It’s a three-layered structure: an outer oily (lipid) layer that slows evaporation, a middle watery (aqueous) layer that hydrates and nourishes, and an inner mucin layer that helps tears stick to the surface of your eye. Dry eye happens when any of these layers breaks down, and artificial tears are formulated to reinforce one or more of them.
Most artificial tears work by adding a lubricating substance that spreads across the eye’s surface, holding moisture in place longer than water alone would. Some ingredients cling to the mucin layer, extending how long the drop stays on your eye before draining away. Others contain oils to slow evaporation or protective compounds that shield corneal cells from damage caused by excessive saltiness in an unstable tear film.
What’s Inside the Bottle
The FDA recognizes six categories of active ingredients for over-the-counter artificial tears: cellulose derivatives, dextran, gelatin, liquid polyols, polyvinyl alcohol, and povidone. The most widely used is sodium carboxymethylcellulose (CMC), a plant-derived compound that thickens the drop so it coats the eye longer. Other common thickening agents include hyaluronic acid, which has natural mucus-like properties that help it adhere to the eye’s surface, and hydroxypropyl guar, a gel-forming polymer.
Beyond the lubricant itself, formulations typically include electrolytes like sodium, potassium, calcium, and magnesium. These mirror the mineral profile of healthy tears and help maintain the right salt balance on the eye’s surface. Some drops also contain osmoprotectants, compounds like glycerin, trehalose, or carnitine that protect corneal cells from the stress of dehydration. Trehalose in particular has been shown to stabilize cell membranes and support healing of the corneal surface.
Types of Artificial Tears
Aqueous (Water-Based) Drops
The majority of artificial tears on the market are aqueous-based. These are thin, easy to apply, and cause minimal blurring. They work best when your eyes simply aren’t producing enough of the watery component of tears. Most people start here, and for mild to moderate dryness, a standard aqueous drop used a few times a day is often enough.
Lipid-Based Drops
If your dryness is caused by tears evaporating too quickly rather than not being produced, a lipid-containing drop may work better. This type of evaporative dry eye is often linked to dysfunction of the meibomian glands, the tiny oil-producing glands along your eyelid margins. Lipid-based drops typically contain an oil like castor oil to replenish that outer protective layer and slow evaporation. Studies have confirmed their effectiveness across all types of dry eye, though they’re specifically recommended for lipid-deficient cases. Formulations with a 2% castor oil concentration have been shown to help with meibomian gland dysfunction without causing significant blurred vision.
Gels and Ointments
Higher-viscosity gels stay on the eye longer than standard drops, making them useful for more severe dryness. The trade-off is temporary blurred vision after application. Ointments are the thickest option, essentially a petroleum or mineral oil base that forms a long-lasting protective layer. Most people use ointments only at bedtime because the blurring makes daytime use impractical. If you wake up with eyes that feel dry, gritty, or stuck shut, a nighttime ointment can make a noticeable difference.
Preserved vs. Preservative-Free
Many artificial tears contain preservatives to prevent bacterial growth in the bottle after opening. The most common is benzalkonium chloride (BAK), which can irritate the eye’s surface with repeated use. The American Academy of Ophthalmology recommends limiting preserved drops to no more than four times a day. If you need drops more frequently than that, preservative-free versions are the better choice.
Preservative-free drops come in single-use vials. You twist off the top, apply the drops, and discard the vial. They’re generally safe to use as often as you need them. Some newer multi-dose bottles use alternative preservative systems that break down on contact with the eye, offering a middle ground between convenience and gentleness. Despite the theoretical advantage, a systematic review of clinical trials found no statistically significant difference in symptom scores, tear production, or tear stability between preserved and preservative-free drops. Neither group showed notable side effects. Still, if you’re using drops frequently or have sensitive eyes, preservative-free is the safer long-term bet.
How to Apply Eye Drops Properly
Getting the most out of artificial tears depends partly on technique. Tilt your head back and look up. With one hand, pull your lower eyelid down and away from your eye to create a small pocket. With the other hand, hold the bottle upside down with the tip just above that pocket, then squeeze one drop in. After applying, close your eye and press gently on the tear duct (the small hole at the inner corner of your eye near your nose) for at least one minute. This keeps the drop from draining into your nasal passage and gives it more time to absorb.
If you use more than one type of eye drop, wait at least five minutes between each one so the first drop isn’t washed away by the second. To avoid contamination, wash your hands before use, never touch the bottle tip with your fingers, and don’t let the tip contact your eye or eyelid.
Safety and Product Quality
Artificial tears are generally very safe, but product quality matters. In late 2023, the FDA warned consumers to stop using 26 over-the-counter eye drop products after investigators found unsanitary conditions and bacterial contamination at a manufacturing facility in India. The affected brands included store-brand products sold at CVS, Walmart (Equate), Rite Aid, Target (Up & Up), and others under the Leader and Rugby labels. Multiple voluntary recalls followed. The contamination posed risks of serious eye infections that could lead to partial vision loss or blindness.
This doesn’t mean artificial tears as a category are dangerous, but it’s worth paying attention to the brand you choose. Stick with well-established manufacturers, check the FDA’s recall page if you’re unsure about a product, and never use drops that look cloudy or discolored or that have passed their expiration date.
Choosing the Right Product
With so many options, picking an artificial tear can feel overwhelming. A few practical guidelines help narrow things down. If your dryness is mild and occasional, a basic aqueous drop with CMC or hyaluronic acid will likely work fine. If your eyes feel worse in windy or dry environments and your eyelids look oily or clogged, try a lipid-based formula. If you need drops more than four times a day, choose preservative-free. And if your symptoms are worst in the morning, add a nighttime gel or ointment.
There’s no single “best” artificial tear. Different formulations work better for different people, and some trial and error is normal. If over-the-counter drops aren’t providing enough relief after a few weeks of consistent use, that’s worth bringing up with an eye care provider, since persistent dry eye sometimes has underlying causes that drops alone won’t address.