If you have dry eyes, the first thing you probably reach for is a bottle of eye drops. But like so many health products, the sheer variety of eye drops available can be overwhelming, and not all are created equal.

When it comes to individual products, the drops that work best for your dry eyes may not work as well for someone else. There are a few things to consider during your search for the best eye drops for dry eyes, and when in doubt, never hesitate to ask your eye doctor for advice.

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There are two main types of over-the-counter eye drops for dry eyes: moisturizing artificial tears and lubricating gel drops.

• Liquid artificial tears are exactly what they sound like — a method of adding moisture to the eyes that mimics natural tears. They’re usually designed to be used more often throughout the day, but with a shorter effect. Liquid eye drops tend to be better for people with mild to moderate dryness.

• Gel lubricating drops are also artificial tears, but they focus more on lubrication. The drops add a thicker gel-like film to the surface of the eye to mirror the natural oils in our tears. While the effects last longer than liquid drops, the gel layer can temporarily blur your vision while it settles. People with more severe cases of dry eye tend to prefer these products.

• Redness relief eye drops are also available. While they can help with dryness, their main focus is to shrink the blood vessels near the eye’s surface to reduce redness. However, it’s important to stay mindful of the “rebound effect” of redness relieving eye drops. Harvard Medical School recommends treating red eyes with standard artificial tears — or simply waiting for redness to go away on its own. Speak with your eye doctor if you aren’t sure what’s causing eye redness, dryness or other irritation.

Many major brands produce dry eye drops that are available for purchase at supermarkets or drug stores across the country. They can come in bottles or packs of single-use vials.

Some of the most popular over-the-counter drops recommended by eye doctors include:

TheraTears

Type: Liquid artificial tears

Expect to pay: About $8 to $10 for a 15mL bottle

TheraTears is one of the most popular eye drops for frequent use. It could be a good option for people who are sensitive to preservatives, since it uses a special chemical that dissolves on contact.

Refresh Tears

Type: Liquid artificial tears

Expect to pay: About $9 to $12 for a 15mL bottle

Refresh Tears are used for short-term relief of dry eye symptoms like irritation, burning and overall discomfort. Like other artificial tears, they are specially formulated to replicate the effect of your natural tears.

Blink GelTears

Type: Gel lubricating drops

Expect to pay: About $8 to $12 for a 10mL bottle

Blink GelTears provide a “thicker, more viscous lubricating formula” to help daytime and nighttime dryness. The gel version is labeled for moderate to severe dry eye, while mild to moderate cases are directed toward non-gel drops called Blink Tears.

Systane Gel Drops

Type: Gel lubricating drops

Expect to pay: About $10 to $14 for a 10mL bottle

Systane Gel Drops use their thickest formula to “create a protective shield over the eyes” for longer periods of time. Systane also offers similar gel drops specifically for nighttime use.

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Many dry eye drops contain preservative chemicals to keep bacteria, fungi and other harmful microscopic organisms from growing inside the bottle. The result is safe and sterile eye drops, but like the preservatives in food, there can be drawbacks.

Some people are sensitive to the preservatives in eye drops and develop red, irritated or itchy eyes after using them. Additionally, the Review of Ophthalmology states that long-term preservative exposure may damage certain cells in the cornea and outer layer of the eye.

For these reasons, eye doctors usually advise against using eye drops with preservatives more than four times a day, according to the American Academy of Ophthalmology.

Preservative-free versions of popular eye drops for dry eyes are almost always available, but they don’t come in a bottle. Instead, the drops are packaged in a set of single-use vials to eliminate contamination. Single-use vials are typically more expensive per ounce than their bottled counterparts.

Some brands have developed creative alternatives to preservatives. For example, the manufacturer of TheraTears advertises that the preservatives in their eye drops turn into oxygen and water when they come into contact with the eye.

Prescription eye drops are usually reserved for more severe cases of dry eye, like those caused by eye injuries or conditions like Sjogren’s Syndrome.

A prescription eye drop medication called Restasis is often seen as a gold standard among people who suffer from severe forms of dry eye. The cyclosporine drops are generally safe and well-tolerated by patients, according to Johns Hopkins.

The prescription eye drops Cequa and Xiidra also use a similar cyclosporine formula to increase tear production.

Eye drops like Restasis work by suppressing the immune response, therefore reducing inflammation in the eye’s tear ducts. They can provide significant relief, but it can take several weeks or months for the effect to become noticeable.

READ MORE: Home remedies for dry eyes

Some cases of dry eye require more than eye drops, depending on the severity and underlying cause. An eye doctor can examine your eyes and perform a Schirmer's test to determine the quality of your tears. Your doctor may also be able to suggest dietary changes and supplements to increase tear production.

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