Depression is a mental disorder that is presented by depressed mood, loss of interest or pleasure, decreased energy, feelings of guilt or low self-worth, disturbed sleep or appetite, and poor concentration. These problems can become chronic or recurrent and lead to substantial impairments in an individual's ability to take care of his or her everyday responsibilities. Oral drug delivery has been for decades the most widely utilized route of administration among all the routes that have been explored for the systemic delivery of drugs. The reasons that the oral route achieved such popularity...