Isopropyl Cloprostenate

Isopropyl Cloprostenate is a synthetic prostaglandin analogue listed as a hair-conditioning agent. CIR is reviewing it with ethyl TafluprostamideEthyl TafluprostamideEmergingEthyl Tafluprostamide · Synthetic prostaglandin analogueProstaglandin analogue used in some lash and brow formulas; US Panel has a revised draft tentative report while EU SCCS already judged related PGAs unsafe for lash/brow growth claims.Open in the Index →; the EU SCCS has already assessed it among three PGAs used for lash and brow growth.[1][2]

What it does

Like other cosmetic PGAs, it is positioned for eyelash and eyebrow appearance via prostaglandin pathways that can also affect the eye and periocular fat.[1][2]

The evidence

CIR’s revised Draft Tentative Report (11 September 2026) follows multiple insufficient-data rounds, including requests for dermal irritation/sensitisation at up to 0.0075% and independent ophthalmology review of iris-colour and related ocular endpoints.[1] SCCS/1680/25 (final 2 February 2026) concluded that isopropyl cloprostenate, methylamido-dihydro-noralfaprostal, and dechloro dihydroxy difluoro ethylcloprostenolamide cannot be considered safe for cosmetic products intended to promote eyelash or eyebrow growth.[2]

How to use it

Read the INCI on lash serums. In the EU, the SCCS opinion is a clear negative for growth-claim use of this analogue; in the US, wait for CIR’s tentative conclusion rather than assuming a Dictionary “conditioning” function equals a clean safety pass.