Dr Ahmir Ahmad

Dr Ahmir Ahmad is a Consultant Gastroenterologist and Specialist Endoscopist at St Mark’s National Bowel Hospital, the UK’s leading specialist centre for bowel disease and a World Endoscopy Organization Centre of Excellence. He sees private patients at Welbeck London, Nuffield Health Brentwood, Spire Hartswood and St Mark’s TrustPlus at Northwick Park, with evening clinics available at Welbeck in central London and Saturday clinics in Brentwood.

He assesses and treats a wide range of digestive symptoms and conditions, including abdominal pain, bloating, reflux, change in bowel habit, rectal bleeding, iron deficiency anaemia, IBS and inflammatory bowel disease. He performs gastroscopy, transnasal gastroscopy, colonoscopy and flexible sigmoidoscopy, and has a particular interest in complex polypectomy and optical and AI-assisted diagnosis.

Dr Ahmad is known for his thoroughness. He goes back to original reports and results rather than relying on summaries, and writes clear, detailed letters explaining the reasoning behind each decision. This makes your care easy to follow from one visit to the next, for you and for any other doctor involved, and is particularly valuable in complex cases and second opinions.

He uses modern techniques, including hybrid water-assisted colonoscopy, which he has researched, to make procedures as comfortable as possible. Around a third of his colonoscopies are performed without sedation, and others with light sedation. For patients who prefer it, anaesthetist-led deep sedation is available at Welbeck. In his audited procedure data, over 98% of colonoscopies were assessed as causing no more than mild discomfort, although every patient’s experience is different. You receive a detailed report on the day of your procedure.

He graduated with distinction from University College London, completed a four-year specialist endoscopy fellowship at St Mark’s under Professor Brian Saunders, and gained his PhD in colonoscopy at Imperial College London, where he is an Honorary Clinical Senior Lecturer. He is an Associate Director of the St Mark’s Academic Institute, Clinical Lead for Optical Diagnosis for NHS England, and Deputy Chair of the British Society of Gastroenterology Endoscopy Clinical Research Group. He led the DISCARD3 study, whose findings on optical diagnosis are now being adopted nationally.

He co-authored the 8th edition of Cotton and Williams’ Practical Gastrointestinal Endoscopy, the internationally renowned textbook used to train endoscopists worldwide, and is first author of the chapter on insertion technique in Waye’s Colonoscopy: Principles and Practice. He co-convened the St Mark’s Hospital Endocation webinar series, which reached audiences in over 100 countries. In 2025 he received the Royal College of Physicians Excellence in Patient Care Award.