Mr Nicholas is a leading consultant ear, nose, and throat (ENT) surgeon with HCA Healthcare, practising at both the London Bridge Hospital and The Harley Street Clinic. Additionally, he holds an NHS consultant post at Lewisham and Greenwich Trust, where he is the lead for head and neck and thyroid tests. His subspecialty is in voice issues and disorders, and he often works with professional voice users. He welcomes clients of all ages and has vast experience in paediatric ENT issues. He also has an interest in salivary gland, thyroid, and parathyroid issues, as well as head and neck cancer.

Mr Nicholas was awarded his medical degree in 1998 from Guy's and St Thomas' Hospital before moving to Australia to broaden his experience. In 2011, he earned a master's degree for his outstanding work on tongue cancers from the University of Sussex, where he received the Gold Medal for best research paper. He is heavily published in his field and remains involved in medical education, organising and teaching courses for other healthcare professionals.

Mr Nicholas is proficient in a range of diseases, medical tests, and treatments, including phonosurgery, general ENT, head and neck cancer, salivary gland surgery, vocal cord disorders, voice problems, thyroid problems, and salivary gland issues. He has been a consultant since 2011 and continues to contribute significantly to his field.