PurposeTo evaluate skin biocompatibility of a nighttime hydrating eyelid gel and possible ocular surface effects in contact lens users (CLU) and non-contact lens users (NCLU). The formulation is registered as a medical device as Tridocosahexaenoine-AOX® (TDHA-AOX) (a concentrated DHA triglyceride), containing also hyaluronic acid (HA). MethodsA prospective, randomized, masked clinical trial was performed with 62 participants of both sexes, aged 20–70 years, split into: (1) CLU (n = 30) and (2) NCLU (n = 32). All participants were instructed to apply a single dose of the moisturizing gel (containing TDHA-AOX and HA) nightly to the upper and inner eyelids of their right eye (RE) only, and during 2 consecutive weeks. Personal interviews, questionnaires, ophthalmic examinations and reflex tear collection were performed. Ophthalmological parameters included ocular surface response and contact lens status. Levels of satisfaction/adverse events were also recorded. Biochemical parameters included basal and final determination of pro-inflammatory mediator molecules in tear samples by multiplex analyses. Statistics were done by the SPSS 24.0 program. ResultsThe CLU group had higher OS dysfunction than NCLU, but overall clinical parameters (corneal staining, and Schirmer/FBUT tests) and OSDI scores showed significant improvement in CLU individuals as compared to the NCLU participants, at the end of study. CLDEQ-8 scores pinpointed significant amelioration in initial risk of developing DEs by applying eyelid gel. Multiplex analyses demonstrated significantly lower VEGF expression levels (p < 0,05) in tears among the CLU compared to NCLU after nightly application of eyelid gel. ConclusionsEyelid gel appeared to safely and efficiently provide hydration and decongestion of the skin and amelioration of the ocular surface during sleep.