Co-incorporation of single or mixed solubilizers significantly improved water uptake/polymer hydration characteristics of Eudragit® RL PO films. Effect of co-incorporation of single (a: 0 (▲) and 20 wt% Tween® 20 (●), Tween® 80 (□), Brij® 98 (△), sodium deoxycholate (○)) or mixed (b: 0 (▲), 40 wt% sodium deoxycholate (●), and 40 wt% sodium deoxycholate + 20 wt% Tween® 80 (■)) solubilizers on polymer hydration/swelling. Fenretinide loading (theoretical) in all the film formulations was 5 wt%. Films containing 20 wt% sodium deoxycholate were prepared using triethyl citrate (20 wt%) as a plasticizer. Films containing 20 wt% surfactants (Tween® 20 and 80, and Brij® 98) were prepared without triethyl citrate. Studies were conducted in simulated saliva (pH 6.8) containing 5%w/v sodium deoxycholate at 37°C and symbols represent mean ± SE, n = 3.