• Queens' College Cambridge BA, MA
• Bart's and the London Medical School - MBBS with distinction
• King's College London - PhD - The role of the gastrointestinal bacteria in the development of irritable bowel syndrome

Inflammatory Bowel Disease (IBD)

Dr Parkes has experience in three major centres in inflammatory bowel disease and now am part of a team of IBD specialists at the Royal London. He has published in this area and is actively involved with clinical trials of novel biological therapies. He has experience in specialist IBD endoscopy, novel biologic agents and complex IBD patients.

He has an active interest in irritable bowel syndrome or IBS, in particular in the role that diet and the gut microbiota play in the causes and treatment for this condition. He has published widely in this field in particular in the role that probiotic preparations can have in the treatment of IBS.

Dr Parkes has a broad range of endoscopic experience and he is competent in a wide range of diagnostic and therapeutic procedures including in the diagnosis of cancer, ulcers, Barrett's oesophagus, colitis, Crohn's disease, diverticular disease and polyps. In particular, he specialises in difficult colonoscopy and polypectomy as well as working as a trainer within the NHS.

• Parkes GC, Whelan K, Lindsay JO.Smoking in inflammatory bowel disease: impact on disease course and insights into the aetiology of its effect. J Crohns and Colitis 2014 Aug 1;8(8):717-25
• Parkes GC, Rayment NB, Hudspith BN, Petrovska L, Lomer M, Brostoff J, Whelan K, Sanderson JD. Distinct microbial populations exist in the mucosa-associated microbiota of sub-groups of irritable bowel syndrome. Neurogastroenterol Motil. 2012 Jan;24(1):31-9
• Parkes GC, Sanderson JD, Whelan K. Treating irritable bowel syndrome with probiotics: the evidence. Proc Nutr Soc. 2010 May;69(2):187-94. 2010 Mar 18.
• Parkes GC, Sanderson JD, & Whelan, K. The mechanisms and efficacy of probiotics in the prevention of Clostridium difficile-associated diarrhoea. Lancet Infect Dis 2009;9:237-244
• Parkes GC, Brostoff, J., Whelan, K. & Sanderson, JD. Gastrointestinal microbiota in irritable bowel syndrome: their role in its pathogenesis and treatment Am J Gastroenterol.2008; 103:1557-1567
• Lomer MC, Parkes GC, Sanderson JD. Review article: lactose intolerance in clinical practice--myths and realities. Aliment Pharmacol Ther 2008;27(2):93-103.

• Inflammatory bowel disease 
• Irritable bowel syndrome including the use of probiotics and dietary therapy 
• Gastro-oesophageal reflux disease 
• Indigestion 
• Coeliac disease
• Bowel cancer 
• Colonic polyps 
• Abnormal liver function

• British Society of Gastroenterology
• European Crohn’s and Colitis Organisation
• Royal College of Physicians