Dr John Meenan is a highly esteemed Consultant Gastroenterologist at Guy's and St. Thomas' Hospital, London. He has been serving in this role since 1999 and has held the position of Chief of the Department. Dr Meenan specialises in general gastroenterology, with a particular focus on endoscopy, colonoscopy, and the advanced technique of endoscopic ultrasound (EUS). His areas of expertise include Irritable Bowel Syndrome (IBS), troublesome acid reflux, heartburn, dyspepsia, and cancer screening.

Dr Meenan qualified with honours from the Royal College of Surgeons in Ireland in 1986. He furthered his training in gastroenterology at St. James's Hospital, Dublin, the Academic Medical Centre, Amsterdam, and Guy's and St. Thomas' Hospital, London. He holds two doctorates: a PhD in Immunology from the University of Amsterdam and an MD in Biochemistry from Trinity College, Dublin. Additionally, he has a Diploma in Statistics from Trinity College, Dublin.

Dr Meenan is a member of the British Society of Gastroenterology and has been chairman of the UK/Ireland EUS Users' Group. He has also served on the International Committee of the American Society for Gastrointestinal Endoscopy (ASGE). His endoscopy results are independently audited every six months and consistently exceed national standards.

Dr Meenan is committed to patient care, often using email for follow-ups to minimise unnecessary hospital visits. He avoids invasive tests when alternatives are available and advises on tests that can be done through NHS family doctors for self-paying patients or those with limited insurance cover. His dedication to teaching has been recognised with the prestigious "Teachers" award by the American Endoscopy Society (ASGE) in 2007 and 2013.