Lash-lengthening drug Latisse can make your eyelashes longer — but it can have some pretty hardcore side effects for a cosmetic. The FDA has issued a warning letter to the manufacturer (PDF) of the glaucoma-drug-turned-cosmetic-product, saying that many claims on its website are misleading and, in fact, unlawful.

CR Health breaks it down for us:

Latisse’s Website says:
In the “Is Latisse safe?” section of the drug’s website: “The FDA reviewed clinical study results to verify the identity, potency, purity and stability of the ingredients, and demonstrated that the product is safe and effective for its intended use if used as prescribed.”

The FDA says:
This description is misleading and it fails to mention that Latisse may have side effects, or mention any of those side effects. It also implies, according to the FDA, that Latisse is “especially safe because the FDA has verified the identity, potency, purity, and stability of the ingredients.”

Latisse’s Website says:
The website also answers the question, “Why do the directions say to only apply Latisse solution to the base of the upper eyelashes?” by saying: “A clinical trial of Latisse was conducted on patients who applied the product to the base of their upper lashes only. Applied nightly, the transfer of Latisse solution from the upper to lower eyelid may occur naturally because the eyelids are closed and the eyelashes touch each other.”

The FDA says:
The answer fails to warn users of the real reason why Latisse should not be applied to the lower eyelid: If Latisse comes in continued contact with skin outside the treatment area, it could lead to excess, unwanted hair growth.

Latisse’s Website says:
The Latisse website claimed that “increased brown iris pigmentation has occurred when similar medications were instilled directly into the eye to treat elevated intraocular pressure/glaucoma.”

The FDA says:
In fact, the “similar” medication was actually the same medication. Both Latisse and Lumigan, a glaucoma drug also from Allergan, are actually bimatoprost ophthalmic solution. Though Latisse is applied differently, brown iris pigmentation has been reported from use of the drug. The FDA says, “by omitting this material information and suggesting this side effect has only occurred with ‘similar’ medications, this claim minimizes the risk of increased iris pigmentation.”

Latisse’s website says:
The site repeatedly mentions that the eye redness and itching that can accompany the use of Latisse are “not allergic reactions.”

The FDA says:
That’s misleading. In fact, allergic conjunctivitis is an adverse reaction reported with the use of the active ingredient, bimatoprost ophthalmic solution. Further, these symptoms are usually resolved only after discontinuing treatment with the drug. The FDA was particularly concerned about these claims, according to the letter, “because patients are highly unlikely to be able to differentiate between eye redness associated with conjunctival hyperemia, allergic reaction, or inflammation without the advice of a healthcare provider.”

Yeah, but you look awesome.

FDA warns maker of Latisse about misleading claims [Consumer Reports Health]

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