Mrs Connor, a 32 year old Banker, has presented to see you as she has multiple painful lesions in her mouth. She informs you that she had a similar episode last year for which she was prescribed Hydrocortisone oro-mucosal tablets. This episode has been ongoing for a week and she has been taking her leftover Hydrocortisone tablets but is struggling to eat and drink due to pain. Mrs Connor is keen to try an alternative treatment. She is otherwise fit and well and informs you that she has recently stopped smoking and has stopped drinking coffee.
On examination, there are approximately six oval ulcers measuring approximately one centimetre in diameter. There are no lesions elsewhere. Given a likely diagnosis of aphthous ulcers, which one of the following would be the most suitable treatment to offer Mrs Connor to help with her symptoms?