By Erin Lukas
Mar 23, 2017 @ 3:30 pm
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Whenever we see someone with long, full lashes we immediately assume they’re falsies or extensions. But thanks to lash-growth serums, it is possible to enhance your lashes by adding length and shine to the existing hairs on your lash line.

While there’s a bevy of serums to choose from whether you opt for a prescription formula from a dermatologist’s office or an over-the-counter tube, not all are created equal and won’t deliver the same results.

Before jumping in and slathering a serum on our lashes, we turned to the experts to find out the differences between formulas, potential side effects, and their efficiency.

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Prescription vs. Over the Counter Serums

Currently, Latisse is the only FDA-approved lash growth treatment. In addition to the fact that a doctor needs to prescribe it to you, the formula is derived from a drug used to treat glaucoma, which has been found to enhance both the length and thickness of lashes. “Latisse works by interfering with the eyelash growth cycle using prostaglandin analogues,” explains Great Neck N.Y.-based dermatologist Dr. Jeannette Graf. “This prolongs the eyelash growth cycle resulting in longer and thicker lashes.

On the other hand, OTC serums tend to be more of a conditioning, repairing treatment for lashes. Usually these formulas are enriched with antioxidants and peptides like apple stem extract, biotin, and castor oil, to name a few. While these serums can help lashes appear fuller, it’s important to note that they won’t increase actual lash growth. “The length of lash appearance is different to each individual, but it is important to recognize that only prescriptions like Latisse will actually increase lash growth that will reverse once you stop applying the product,” says NYC-based Cosmetic Dermatologist, Dr. Paul Jarrod Frank.

What Are the Side Effects?

While both prescription and OTC serums are safe to use for any skin type, Dr. Graf recommends avoiding them if you have blepharitis, an inflammatory condition of the conjunctival area where eyelashes originate from, or dry eye because the products could worsen symptoms.

The most common side effects include redness and irritation, which if you experience either, you should immediately stop using the serum. Discoloration of the skin around the eyelids is also a possibility. “It is important to note that some skin discoloration can be a side effect,” says Dr. Frank. “Therefore, it is important to always gently wipe away any excess serum on the eye lid.”

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When Will I See Results?

While each person is different, if you’re using Latisse, Dr. Frank says that doctors who’ve conducted studies have found that most people experienced 25% longer lashes, 18% darker lashes and 106% fuller lashes. Since Latisse has only been approved since 2008, its long-term usage is still being studied, but it’s suggested that you start with the serum once a day for six months, followed by twice a week. Both Doctors, say that since there’s no actual drugs in OTC serums, it’s hard to determine the effect of long-term usage. However, if you experience any side effects, immediately stop applying them.

It’s also important to be realistic with your expectations what the serum will do for your lashes. “When using Latisse, one may expect to regain the long, luscious eyelashes they may have had when they were younger,” Dr. Graf says. “If someone never had eyelashes, using Latisse will not create long lashes since they were never there to begin with.”