Side effects of prostaglandin lash serums are rare but it’s important you know about the potential for these side effects before using them They include iris pigmentation or discolouration of the iris, pigmentation of the eyelid, fat loss around the eye and irritation of the eye. . It can be tricky to see whether or not your lash serum has a prostaglandin analogue in it. PGAs banned for use in cosmetic products in Canada include: . Alprostadil Cloprostenol Dinoprostone Epoprostenol Flurprostenol