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Blow film extrusion is used for the manufacture of polymeric films. This method involves the extrusion of molten polymeric material, which takes the shape of a die into which it is blown, while air blown into it forms a thin film. Due to their significant advantages such as biodegradability, low cost for processing, and nontoxicity, these blown films are finding their applications in the pharmaceutical industry. Chitosan [36], polysaccharides [37], cellulose [38], and their derivatives are the most commonly used biobased polymers in film industries. Increased attention has been gained for the preparation of blown films made from starch‐based materials [39]. Chitosan‐ and starch‐based thermoplastic films have been found to be suitable for applications in pharmaceutical and food processing industries. By increasing the percentage of chitosan in the film, properties such as water vapor and oxygen barrier tend to increase, while the surface hydrophilicity is reduced. Hence, by controlling the amount of chitosan in the film, the rate of degradation of the film, and consequently, its shelf life can be tuned [39].