Prostaglandin analogs in lash growth serums can cause eyelid irritation, itching, allergic reactions, dry eyes, discoloration, darkening of the iris, unwanted hair growth, periorbital fat loss, and eye muscle atrophy. While prostaglandin analogs can be safely be used as prescribed by your healthcare provider, when they appear in non-prescription cosmetic lash serums, consumers can assume the same risks, however, without a medical provider to look out for these risks. | Dr Dray