Chapter 6: Oral Films

Oral films have evolved in two decades from something of a novelty consumer product into an oral dose form used for prescription medicines and with the potential for oral bioavailability enhancement. Oral films are recognised as a distinct dosage form by the current editions of both the USP and Ph. Eur. The main manufacturing methods for films are casting and extrusion, which are well established and understood pharmaceutical manufacturing processes, though flexographic and inkjet printing are increasingly being used to apply drug in reproducible amounts onto specific areas of pre-formed films, enabling the technology to be used for drugs that might not be stable to the usual film-forming conditions. Drug loading capacities of up to 30–50% represent a limitation to the technology, which is exacerbated if significant amounts of flavourings and taste-masking agents are required. This chapter describes film formulations and manufacturing processes, as well as the range of testing that is usually performed on films and highlights specific requirements for films used in the delivery of therapeutic peptides and proteins.