Being from Bay Area, I enjoy providing medical care to patients in northern California. I am excited to be part of the wonderful team of gastroenterologists at Stanford University Medical Center with its multi-disciplinary approach to caring for patients in an integrated healthcare system. I am dedicated to providing high-quality care to my patients while getting to know their personal beliefs so as to involve them in the decision-making process. Based on my education and training, I practice general gastroenterology in addition to performing endoscopies and colonoscopies.

Clinical Focus

  • Gastroenterology
  • Esophagogastroduodenoscopy (EGD)
  • Capsule endoscopy
  • Colonoscopy
  • Dysphagia
  • Eosinophilic Esophagitis
  • Barrett's esophagus
  • GERD
  • Dyspepsia
  • Microscopic colitis
  • Constipation
  • Benign Anorectal Disease
  • General Gastroenterology

Academic Appointments

Administrative Appointments

  • Clinical Assistant Professor, Stanford Healthcare (2016 - Present)

Honors & Awards

  • Howard Hughes Research Scholar, University of California at Berkeley
  • Magna Cum Laude, Department of Molecular and Cellular Biology, University of California at Berkeley
  • Dean's List, Saint George's University, School of Medicine

Professional Education

  • Medical Education: St George's University School of Medicine Grenada West Indies (2009) NY West Indies
  • Board Certification: American Board of Obesity Medicine, Obesity Medicine (2021)
  • Board Certification, Internal Medicine, American Board of Internal Medicine (2012)
  • Board Certification, Gastroenterology, American Board of Internal Medicine (2016)
  • M.D., Saint George's University School of Medicine
  • B.A. Magna Cum Laude, University of California at Berkley, Molecular and Cellular Biology

Graduate and Fellowship Programs

  • Gastroenterology & Hepatology (Fellowship Program)

All Publications

  • Marijuana, Ondansetron, and Promethazine Are Perceived as Most Effective Treatments for Gastrointestinal Nausea. Digestive diseases and sciences Zikos, T. A., Nguyen, L., Kamal, A., Fernandez-Becker, N., Regalia, K., Nandwani, M., Sonu, I., Garcia, M., Okafor, P., Neshatian, L., Grewal, D., Garcia, P., Triadafilopoulos, G., Clarke, J. O. 2020


    BACKGROUND: Many anti-nausea treatments are available for chronic gastrointestinal syndromes, but data on efficacy and comparative effectiveness are sparse.AIMS: To conduct a sectional survey study of patients with chronic nausea to assess comparative effectiveness of commonly used anti-nausea treatments.METHODS: Outpatients at a single center presenting for gastroenterology evaluation were asked to rate anti-nausea efficacy on a scale of 0 (no efficacy) to 5 (very effective) of 29 commonly used anti-nausea treatments and provide other information about their symptoms. Additional information was collected from the patients' chart. The primary outcome was to determine which treatments were better or worse than average using a t test. The secondary outcome was to assess differential response by individual patient characteristics using multiple linear regression.RESULTS: One hundred and fifty-three patients completed the survey. The mean efficacy score of all anti-nausea treatments evaluated was 1.73. After adjustment, three treatments had scores statically higher than the mean, including marijuana (2.75, p<0.0001), ondansetron (2.64, p<0.0001), and promethazine (2.46, p<0.0001). Several treatments, including many neuromodulators, complementary and alternative treatments, erythromycin, and diphenhydramine had scores statistically below average. Patients with more severe nausea responded better to marijuana (p=0.036) and diphenhydramine (p<0.001) and less so to metoclopramide (p=0.020). There was otherwise no significant differential response by age, gender, nausea localization, underlying gastrointestinal cause of nausea, and GCSI.CONCLUSIONS: When treating nausea in patients with chronic gastrointestinal syndromes, clinicians may consider trying higher performing treatments first, and forgoing lower performing treatments. Further prospective research is needed, particularly with respect to highly effective treatments.

    View details for DOI 10.1007/s10620-020-06195-5

    View details for PubMedID 32185665

  • Pre-Pylorus Pseudomelanosis - "It Can Happen" Bilal, M., Grewal, D. K., Clarke, K. W B SAUNDERS CO-ELSEVIER INC. 2015: S319–S320
  • Cardiovascular health among Asian Indians (CHAI): a community research project. Journal of interprofessional care Ivey, S. L., Patel, S., Kalra, P., Greenlund, K., Srinivasan, S., Grewal, D. 2004; 18 (4): 391-402


    The object of this research was to assess cardiovascular (CV) risks in Asian Indians in California. We conducted eight focus groups and a pilot survey using community-based participatory research (CBPR) methods. Focus groups were held in six communities. Surveys were conducted by telephone or in person in areas selected for high population densities of Asian Indians. We selected focus group subjects by snowball sampling (n = 57). We held six English and two Punjabi groups. We used a surname-based phone list from three area codes for telephone interviews (n = 254). We added 50 in-person interviews for comparison (total n = 304) and did 50 interviews in Punjabi. We held community meetings for dissemination. Focus groups discussed CV risks; themes developed aided survey development. In-person and telephone surveys were feasible. Telephone surveys were more gender-balanced and people more often answered alcohol, tobacco, and income questions. Self-reported prevalences for hypertension, hypercholesterolemia, and diabetes were 20.4, 35.3 and 10.6%, respectively. Only 11.9% of persons reported ever smoking cigarettes. It was concluded that CBPR methods were effective in this exploratory study assessing CV risks in Asian Indians. Hypertension, high cholesterol, and diabetes were more prevalent in participants than the population average; other risk factors were less common (tobacco).

    View details for PubMedID 15801554