This opinion presents the safety evaluation of three prostaglandin analogues in cosmetic products. After reviewing all submitted evidence, the EU Scientific Committee on Consumer Safety (SCCS) determines that Dechloro Dihydroxy Difluoro Ethylcloprostenolamide (DDDE), Isopropyl Cloprostenate (IPCP), and Methylamido-Dihydro-Noralfaprostal (MDN) are unsafe for use in cosmetics intended for eyelash and eyebrow growth, due to their strong pharmacological activity and insufficient data to exclude reproductive or developmental toxicity. SCCS further notes that, although the three PGAs show no genotoxic potential, non-genotoxic carcinogenicity cannot be ruled out in the absence of relevant studies.