Alpha lactose monohydrate and powdered cellulose are functional excipients commonly used in oral solid preparations. Both are of natural origin and have long been used in the pharmaceutical industry. In order to achieve synergy between the two, such as improving compressibility and mixing properties, using a common spray drying process, we obtained a co-processing excipient-Cellactose® 80. This co-processed complex contains 75% alpha monohydrate and 25% powdered cellulose, all retaining their original chemical properties.