I wear the product every night on the upper and lower eyelid. Until now I had fortunately no side effects, but have to say that I am very sparingly and carefully orders to also. Lt. Manufacturers should hold about 6 months the 3.5ml bottle. But because it used up and down, I suppose it was a shorter period of time. In a week or two I'll apply it only 2-3 times a week. This should lt. Manufacturer is sufficient to preserve the long eyelashes permanently. I do not want to do without it frankly. This dense lash line makes the eye appear quite different.
Personally, I would highly recommend this product, even if it is not cheap. I'll buy it there again when this bottle is empty.
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