Background: As increased outdoor activities of people, they are more exposed to UV radiation, which causes harmful effects on skin. Silymarin has protective potentials against DNA damage and non-melanoma skin cancers, and also it has anti-oxidant, anti-inflammatory, and immune regulation characteristics. Nano formulation of plant material showed to be more effective than common ones.

Objective: In present study, nano-formulated silymarin was used in a cream, and its effects were investigated against destructive effects of UV rays.

Methods: Silymarin standardized extract was prepared, nano formulated in cream base, and applied to skin of the animals. Four groups of animals (n=15) were examined Group 1 without any treatment (control), Group 2 Vaseline, Group 3 nano-formulated silymarin extract cream, and Group 4 silymarin-carnosine. UV was radiated on the shaved area of the four groups for 45 minutes with dose of 180 mJ/cm². Dermal scaling, skin irregularity, erythema, skin hyperpigmentation, and edema were evaluated in animals. Histopathological observation was done on the skin samples of the animals.

Results: silymarin nano-formulation was effective in decreasing both physical damages and histopathological injuries significantly.