RapidLash is a cosmetic product claiming to grow lashes. Like many companies with their version of lash-growing products, RapidLash wants to compete with Allergan’s expensive prescription-only version called Latisse ($160 for 0.1 ounce). Most of these Latisse-wannabes are nothing more than colorless liquid eyeliners with some peptides thrown in that have no research showing they can affect hair growth. RapidLash stands apart not only because it costs considerably less than Latisse but it does, at least in theory, work to grow lashes.

A serious distinction between Latisse and RapidLash is that Latisse is a prescription-only drug. Therefore, it is subjected by the FDA to intense scrutiny, proof of safety, and proof of efficacy. Because RapidLash is a cosmetic, it is not subject to these same requirements. Rocasuba, the company that distributes RapidLash, has done some amount of their own testing, but it pales in comparison to the level of testing Latisse went through to prove what it can and can’t do and what risks accompany its benefits.

Claims for RapidLash are carefully worded so they remain strictly cosmetic and not like a drug but here’s the difference: RapidLash does contain an ingredient that quite possibly allows it to work like Latisse. The active ingredient in Latisse is bimatoprost. Bimatoprost is the active ingredient in the prescription medication Lumigan used to treat glaucoma. Patients with glaucoma who used Lumigan noticed their eyelashes really grew and got darker. Allergan owns Lumigan and so they took advantage of this side effect and obtained FDA approval to sell this active ingredient as a lash growing treatment.

RapidLash contains an ingredient called isopropyl cloprostenate, which has some distant molecular similarities to bimatoprost. While there is no published research showing isopropyl cloprostenate can grow lashes, its relation to bimatoprost clearly exists. This association is the likely explanation behind RapidLash’s runaway success. A quick Google search produces thousands of online “fans” all attesting to its efficacy.

Given there is evidence that RapidLash could work similarly to Latisse, it is therefore possible that the same side effects associated with Latisse could occur when using RapidLash as well. Bimatoprost can cause irritation, redness, a bluish skin discoloration around the eye that could be permanent, and a permanent change in eye color among other potential problems anyone considering Latisse should be told about. The company selling RapidLash says they have no research or evidence showing these risks exist for their product, but their research is not reviewed by the FDA nor are they required to perform the mandatory safety and efficacy tests for drugs required by federal law. However, it is reassuring that the company has made the efforts to ensure the safety of RapidLash, and they willingly provided these documents to us.

So should you consider trying RapidLash for longer lashes and fuller eyebrows? The Cosmetics Cop Team is leaving this product unrated and not making a conclusion one way or the other. There just isn’t enough substantiated information to make a clear recommendation. For your own eye health, if you do decide to try RapidLash, or Latisse for that matter, watch for any negative side effects as mentioned above and it never hurts to check with your doctor first. Bottom line: RapidLash should work, at least in theory, to produce the results you want.

Paula and I get lots of requests to review the glut of lash growth products being sold. We’ve covered the big ones, but there was one we hadn’t reviewed until recently: RapidLash. After analyzing the formula and scouring published research to serve as the basis for our review, we came to the following conclusion: RapidLash doesn’t work as claimed.

I am sure many women were disappointed, as they really wanted to believe this was a slam-dunk alternative to prescription lash-growth product Latisse (which really does work and, unlike RapidLash, is supported by published studies confirming its efficacy). After all, RapidLash is widely available (I’m surprised I haven’t seen it sold at my local Safeway, right there in the checkout aisle) and, at $49.95 per tube, is a relative bargain compared to Latisse.

Even though we couldn’t find any ingredient in RapidLash that is proven to grow longer, thicker, darker lashes (and eyebrows), the number of online comments from women who use this product were too great to ignore. In fact, I mentioned this in our review: “What I can’t account for is the number of women who’ve tried RapidLash and swear that it worked for them. You can find pages and pages of positive reviews for this product, not to mention a legion of fans on Facebook, and endless mentions in fashion magazines.” Even though we presented this perspective, it hasn’t stopped several women from writing to us, describing our assessment of RapidLash as unfair, one-sided, or just plain wrong.

Sigh. I admit, to some extent, I expected a bit of a backlash. After all, if RapidLash works for you you’ll know it: the results are staring back at you with each glance in the mirror. It could be (and probably is) a placebo effect, something that often happens in the cosmetic industry, but that doesn’t change the emotional personal experience. However, there may be another reason we hadn’t considered before. Given that RapidLash doesn’t contain anything proven to grow longer, thicker lashes, perhaps the company that makes it (International Research Laboratories) is using something in their product without revealing to consumers what it is. We have no proof that this is true—it’s merely speculation on our part—but it would explain why women are seeing results if it isn’t just a placebo effect.

Arkansas plastic surgeon Dr. Ramona Bates also thinks something may be amiss with RapidLash. Why? As she reports on emaxhealth.com, there have been concerns from consumers over irritation along the lash line and pigmentation changes to the eye from RapidLash, two potential side effects for the prescription eyelash growth product Latisse. We know Latisse’s active ingredient and how it functions. We also know its potential side effects, which include what some users of RapidLash have reported. Whether or not there’s a legitimate connection has yet to (and may never) be confirmed. If it were me, and I have used lash growth products in the past, I’d go for the one with research behind its formula, not to mention up front information about safety concerns and known side effects. That means Latisse, even though it’s more expensive and requires a prescription. When it comes to the health and safety of your eyes, why wouldn’t you go with what’s been proven safe and effective rather than a similar product awash in the art of cosmetic claims?