William Snape, M.D. , Scientist; Gastroenterologist, Medical Director of the Center for Neurogastroenterology and Motility Services at CPMC

California Pacific CURRENTS: The online journal of CPMC Research Institute

Improving the management of gastrointestinal motility disorders
  • Pyloric pressures in patients with gastroparesis

    Patients with documented gastroparesis can have multiple causes of their slow gastric emptying. Pyloric pressures appears elevated in two-thirds of patients.  Reducing pyloric pressure to normal levels can remove one of the causes of the patient’s symptoms.  Botulinum toxin reduces pressure. If the patient has improvement of symptoms and gastric emptying after botulinum toxin, definitive therapy with pyloroplasty can be performed.



Research Overview

  • As Medical Director of the Center for Neurogastroenterology and Motility Services at CPMC, Dr. Snape investigates new diagnoses and treatments for gastroparesis, inflammatory bowel disease, irritable bowel syndrome, severe constipation, gastroesophageal reflux disease, and fecal incontinence. He is board certified in internal medicine.
  • His research at the Center is part of the National Institutes of Health Gastroparesis Registry—an observational study following the natural history, clinical course, and outcomes of gastroparesis.
  • Dr. Snape’s group is leading clinical trials assessing aprepitant for chronic nausea and vomiting, and the efficacy of continuous glucose monitoring and insulin pump therapy in diabetic gastroparesis.


Dr. Snape obtained his M.D. from Jefferson Medical College in Philadelphia, Pennsylvania. He completed a residency at Albert Einstein College of Medicine in New York, and a fellowship in gastroenterology at the Hospital of the University of Pennsylvania in Philadelphia.


Publication Search


Grover M, Gibbons SJ, Nair AA, Bernard CE, Zubair AS, Eisenman ST, Wilson LA, Miriel L, Pasricha PJ, Parkman HP, Sarosiek I, McCallum RW, Koch KL, Abell TL, Snape WJ, Kuo B, Shulman RJ, McKenzie TJ, Kellogg TA, Kendrick ML, Tonascia J, Hamilton FA, Farrugia G, NIDDK Gastroparesis Clinical Research Consortium (GpCRC)., Transcriptomic signatures reveal immune dysregulation in human diabetic and idiopathic gastroparesis. BMC Med Genomics

Calles-Escandón J, Koch KL, Hasler WL, Van Natta ML, Pasricha PJ, Tonascia J, Parkman HP, Hamilton F, Herman WH, Basina M, Buckingham B, Earle K, Kirkeby K, Hairston K, Bright T, Rothberg AE, Kraftson AT, Siraj ES, Subauste A, Lee LA, Abell TL, McCallum RW, Sarosiek I, Nguyen L, Fass R, Snape WJ, Vaughn IA, Miriel LA, Farrugia G, NIDDK Gastroparesis Clinical Research Consortium (GpCRC)., Glucose sensor-augmented continuous subcutaneous insulin infusion in patients with diabetic gastroparesis: An open-label pilot prospective study. PLoS One

Siraj ES, Homko C, Wilson LA, May P, Rao AD, Calles J, Farrugia G, Hasler WL, Koch KL, Nguyen L, Snape WJ, Abell TL, Sarosiek I, McCallum RW, Pasricha PJ, Clarke J, Tonascia J, Hamilton F, Parkman HP, Islet Cell Associated Autoantibodies and C-Peptide Levels in Patients with Diabetes and Symptoms of Gastroparesis. Front Endocrinol (Lausanne)

Gibbons SJ, Grover M, Choi KM, Wadhwa A, Zubair A, Wilson LA, Wu Y, Abell TL, Hasler WL, Koch KL, McCallum RW, Nguyen LAB, Parkman HP, Sarosiek I, Snape WJ, Tonascia J, Hamilton FA, Pasricha PJ, Farrugia G, Repeat polymorphisms in the Homo sapiens heme oxygenase-1 gene in diabetic and idiopathic gastroparesis. PLoS One

Pasricha PJ, Yates KP, Sarosiek I, McCallum RW, Abell TL, Koch KL, Nguyen LAB, Snape WJ, Hasler WL, Clarke JO, Dhalla S, Stein EM, Lee LA, Miriel LA, Van Natta ML, Grover M, Farrugia G, Tonascia J, Hamilton FA, Parkman HP, NIDDK Gastroparesis Clinical Research Consortium (GpCRC)., Aprepitant Has Mixed Effects on Nausea and Reduces Other Symptoms in Patients With Gastroparesis and Related Disorders. Gastroenterology

Orthey P, Yu D, Van Natta ML, Ramsey FV, Diaz JR, Bennett PA, Iagaru AH, Fragomeni RS, McCallum RW, Sarosiek I, Hasler WL, Farrugia G, Grover M, Koch KL, Nguyen L, Snape WJ, Abell TL, Pasricha PJ, Tonascia J, Hamilton F, Parkman HP, Maurer AH, NIH Gastroparesis Consortium., Intragastric Meal Distribution During Gastric Emptying Scintigraphy for Assessment of Fundic Accommodation: Correlation with Symptoms of Gastroparesis. J Nucl Med

William Snape, M.D.  , Scientist; Gastroenterologist, Medical Director of the Center for Neurogastroenterology and Motility Services at CPMC
Primary Research Interests
  • Management of gastroparesis and other gastrointestinal motility disorders

Gastroenterology and Interventional Endoscopy Clinical Trials