There are two main possible side effects that you may hear about with lash serums that contain prostaglandin analogues: eyelid discoloration and periorbital fat loss, or fat loss around the eyes, which is also something that happens naturally as you age. In my experience using GrandeLash for around three months, I didn’t really experience any discoloration. Though I have some friends who have used the product that did result in discoloration. One friend experienced some redness, so she stopped using the product. Another had discoloration that she said has lasted for years. A third friend experienced some redness, so reduced the application to every other day and hasn’t had any issues since. Zeichner adds, “Application of topical prostaglandin-containing products are not without potential side effects. They have been reported to cause hyperpigmentation or darkening of the skin around the eyes, which can be long lasting, in some cases for months.” If you experience any hyperpigmentation, Zeichner assures, “It will improve on its own over time, and the same type of skin brightening ingredients used for other forms of hyperpigmentation can help treat it.” Hernandez adds, “Darkening of the lash line is usually temporary for the duration of application of the product plus 14+ days after stopping.”
What about fat loss around the eye? Grande attests, “In our 90-day consumer perception study, we did not find issues pertaining to periorbital fat loss and stand behind GrandeLash-MD as a safe cosmetic product.” Yet, if you cruise TikTok on the subject, some users claim prostaglandins have changed their eye shape, making their eyelid larger, or even giving those with monolids a fold. Other users say they love the way it makes hooded eyelids look less hooded. When I look at my before and after photos, it does appear that the part of my eyelid below the crease looks subtly larger and overall my eyelids look a bit less hooded. Hernandez examined my before and after images and said, “The good news is that your lashes had incredible results with zero fat loss.” If you do have these effects, how long do they last? “Unfortunately, loss of fat is permanent,” Zeichner says.
If you look at any retailer’s reviews for GrandeLash-MD, from Sephora to Amazon, the vast majority are positive. When I asked Grande about the potential side effects, she said, “We pride ourselves on our extensive third-party testing to ensure the safety of our product.” The product has been around for fifteen years, and Grande shared some of the testing GrandeLash has undergone: industry standard RIPT testing concluded that the product does not present potential for dermal irritation or allergic contact sensitization, ophthalmologist testing has concluded that it is safe for use with contacts and lash extensions, and HET-CAM testing has graded its irritation potential at the lowest possible rating scale: none to slight.
My advice would be to take it slow and apply exactly as directed, and slow or stop use right away at the first sign of any side effects. Overall, it’s more than likely that you’ll be one of the many happy customers like yours truly.