About

David C. Kunkel is an Associate Clinical Professor of Medicine at UC San Diego, specializing in gastroenterology. He completed his medical degree at the University of New Mexico in 2008, followed by internship and residency in Internal Medicine at Cedars-Sinai Medical Center, and a fellowship in Gastroenterology at UCLA. His research focuses on gastrointestinal health, including gastric electrical activity, gastroparesis, irritable bowel syndrome, and related disorders. He has contributed to understanding the gut-brain connection, gastrointestinal monitoring technologies, and healthcare resource utilization in digestive diseases. Dr. Kunkel is involved in clinical trials and research activities supported by NIH grants, and he has published extensively on topics related to gastrointestinal physiology, diagnostics, and treatment.

Research topics

• Medicine
• Computer Science
• Gastroenterology
• Internal medicine
• Materials science
• Biomedical engineering
• Computer hardware
• Surgery
• Nanotechnology
• Chemistry

Selected publications

• Genetic Deletion of Muc5b Reduces Interstitial Lung Disease in Neonatal Nedd4-2 Deficient Mice

  Klinische Pädiatrie · 2026-02-01

  article
  PublisherDOI

• Revisiting the Incidence of Tardive Dyskinesia With Oral Metoclopramide Use: A Real‐World Epidemiology Study (2011–2020)

  Neurogastroenterology & Motility · 2026-01-01 · 1 citations

  articleOpen accessSenior author

  BACKGROUND: Gastroparesis is a debilitating disorder with limited treatment options, and metoclopramide remains the only FDA-approved pharmacologic therapy. Concerns about metoclopramide-induced tardive dyskinesia (TD) are based on older studies with inconsistent incidence estimates (1%-15%). A reassessment of metoclopramide's TD risk is needed. METHODS: A retrospective cohort study using the MarketScan Research database analyzed TD incidence in adults (2011-2020) with at least 12 months of medical and pharmacy benefits. TD rates were compared among metoclopramide-treated gastroparesis patients, those untreated, and the general population. Poisson regression models adjusted for person-years (p-yrs) at risk. KEY RESULTS: The incidence of TD among metoclopramide-treated gastroparesis patients was 159.4 per 100,000 p-yrs (0.37%), notably lower than guideline estimates (1%-15%). Comparatively, TD incidence was 121.3 (0.26%) in untreated gastroparesis patients, 51.4 (0.12%) among all metoclopramide users, and 7.6 (0.02%) in the general population. Higher TD rates were observed in older adults (≥ 65 years), females, and in patients with prolonged metoclopramide use, diabetes, psychiatric conditions, Parkinson's disease, or concurrent use of dopamine receptor-blocking agents. Adjusted analyses found no significant independent association between metoclopramide use and increased TD risk in gastroparesis patients. CONCLUSIONS & INFERENCES: TD incidence is uncommon with metoclopramide use and lower than previously estimated in gastroparesis patients. These findings suggest metoclopramide may be a viable treatment option and warrant a reassessment of its risk-benefit profile in gastroparesis management.

  PublisherOA PDFDOI

• The Effectiveness of Plecanatide for Treating Constipation and Bloating in Patients Aged 18 to 40 Years With Irritable Bowel Syndrome: Utilization of a New Composite Trisymptom Endpoint

  Journal of Gastroenterology and Hepatology · 2025-11-10 · 2 citations

  articleOpen accessSenior author

  BACKGROUND AND AIM: Irritable bowel syndrome with constipation (IBS-C) is characterized by multiple sensory symptoms, including abdominal pain, bloating, and bowel habit alterations. Therapeutic response should address all components. This study assesses a new exploratory trisymptom composite efficacy endpoint in an IBS-C population of young adults with bloating treated with plecanatide. METHODS: Pooled data were analyzed from two phase 3, randomized, double-blind trials. Patients (18-40 years) with IBS-C and baseline bloating (score ≥ 1) received plecanatide 3 mg or placebo for 12 weeks. The composite response definition was simultaneous improvement from baseline in three symptoms (abdominal pain, bloating, and complete spontaneous bowel movements [CSBMs]/week) for ≥ 6 of 12 weeks using several thresholds (≥ 2-point or ≥ 30% or ≥ 40% improvement in abdominal pain and bloating plus an increase of ≥ 1 or ≥ 2 CSBMs in the same week). RESULTS: Six hundred and five adults were included (plecanatide [n = 313]; placebo [n = 292]). Plecanatide/placebo baseline mean symptom scores were 6.2/6.4 for abdominal pain and 6.4/6.6 for bloating; both had a mean of 0.2 CSBMs/week. Significantly more patients in plecanatide versus placebo groups (p ≤ 0.01 for all comparisons) were trisymptom composite responders by several stringent thresholds, including ≥ 30% improvement in pain and bloating plus ≥ 1 CSBM/week increase (23.3% vs. 13.4%; p = 0.002) and ≥ 30% improvement in pain and bloating plus ≥ 2 CSBMs/week increase (19.5% vs. 8.9%; p < 0.001). Plecanatide was well tolerated. CONCLUSION: Plecanatide simultaneously and significantly improved combined symptoms of abdominal pain, bloating, and CSBM frequency at varying thresholds. Plecanatide is effective in improving global IBS-C symptoms in individuals with bloating. TRIAL REGISTRATION: ClinicalTrials.gov identifiers-NCT02387359 and NCT02493452.

  PublisherOA PDFDOI

• S1154 Fewer Acute Care and Outpatient Visits With Nasal vs Oral Metoclopramide in Diabetic Gastroparesis: A Real-World Analysis

  The American Journal of Gastroenterology · 2025-10-01

  articleSenior author

  Introduction: Oral metoclopramide (OMCP) is the primary pharmacologic treatment for gastroparesis (GP), but its effectiveness is often limited in patients with delayed gastric emptying, nausea, and vomiting, which impair gastrointestinal absorption. This is particularly challenging in diabetic gastroparesis (DG), where autonomic dysfunction further complicates gastric transit. An intranasal formulation of metoclopramide (NMCP) bypasses the gastrointestinal tract, potentially offering a more reliable route of administration. This study compares the impact of NMCP versus OMCP on healthcare resource utilization (HCRU) over 12 months in patients with type 2 diabetes (T2D) and GP. Methods: We conducted a retrospective real-world evidence study using the Symphony Integrated Dataverse administrative claims data (Jan 2020–Feb 2025). Adult patients with T2D and GP who were initiated on either NMCP or OMCP were identified. Patients were considered to have T2D if they had at least 1 claim for T2D and to have GP if they had a GP diagnosis or had experienced GP symptoms within 12 months prior to treatment initiation. Entropy balancing was applied to adjust for covariates such as age, sex, insurance type, and Elixhauser comorbidity index. HCRU was measured through outpatient visits and acute care episodes, including hospitalizations and emergency room visits. All patients had at least 12 months of baseline data and 12 months of follow-up. Results: The cohort included 372,700 patients with T2D and GP. Of these, the study cohort included 569 were prescribed NMCP (75% women, median age 57) and 56,900 only OMCP (68% women, median age 58); 56% of NMCP patients were initially on OMCP. Over 12 months, NMCP patients had fewer acute care episodes (924/1,000/year) vs OMCP (1,313/1,000/year; ratio 0.7, 95% CI 0.67–0.74), lower outpatient visits (5,391 vs 5,974/1,000/year), and longer median time to hospitalization (12 vs 7 months; P < 0.01). Conclusion: This real-world analysis shows that intranasal metoclopramide is associated with lower healthcare resource utilization compared to oral metoclopramide in patients with diabetic gastroparesis. These results suggest that a non-oral treatment option may offer clinical and economic benefits, particularly in patients whose symptoms impair oral drug absorption. Further prospective studies are needed to confirm these findings.

  PublisherDOI

• S2278 Safety of GLP-1 Agonists With Metoclopramide Nasal Spray in Women With Diabetic Gastroparesis: Insights From a Phase 3 Study

  The American Journal of Gastroenterology · 2024-10-01

  articleSenior author
  PublisherDOI

• Tu1710 FOOT STOOL ENHANCES RECTAL PRESSURE AND FACILITATES THE EVACUATION PROCESS

  Gastroenterology · 2024-05-01

  article1st authorCorresponding
  PublisherDOI

• S2324 Predictive Value of Pyloric Distensibility Measurement for Symptomatic Response After IntrapyloricBotulinumToxin Injection Among Patients With Idiopathic Gastroparesis

  The American Journal of Gastroenterology · 2024-10-01

  article1st authorCorresponding

  Introduction: Gastroparesis is a chronic condition characterized by delayed gastric emptying, leading to symptoms such as nausea, vomiting, early satiety, and abdominal pain. Recent studies indicate that pyloric distensibility, or the ability of the pylorus to stretch, is altered in 30% to 50% of gastroparesis patients, correlating with gastric emptying rates and symptom severity. Intrapyloric botulinum toxin (BT) injection has been proposed to relax the pyloric sphincter and improve gastric emptying, although patient response varies. Identifying predictive markers for symptomatic response is essential to optimize patient selection and treatment outcomes. Methods: Pyloric distensibility was measured in 19 idiopathic gastroparesis patients (mean age: 46.26±22 years) using the EndoFLIP system (Medtronic) post intrapyloric BT injection. Total symptomatic score (TSS) was assessed prospectively before and 3 months after BT injection. Data were analyzed using EndovizX software (Motilitviz, La Jolla, CA) to extract pressure, diameter, and distensibility of the pyloric region from 30cc volume to 10-second point 50cc volume, including mean, standard deviation, minimum, and maximum values. Results: Significant differences were observed between responders (n=7) and non-responders (n=12) (Figure 1). Responders had a significantly higher mean distensibility index (DI; mean DI 12.2 mm2/mm Hg, SD 17.51) compared to non-responders (mean DI 1.57 mm2/mm Hg, SD 1.7), with P-values of 0.024 (1-sided) and 0.048 (2-sided). Maximum DI was also higher in responders (mean 59.28 mm2/mm Hg, SD 76.78) vs non-responders (mean 9.48 mm2/mm Hg, SD 5.09), with P-values of 0.018 (1-sided) and 0.035 (2-sided). Maximum pressure was significantly lower in responders (mean 34.05 mm Hg, SD 19.56) vs non-responders (mean 54.67 mm Hg, SD 19.39), with P-values of 0.02 (1-sided) and 0.04 (2-sided). Maximum diameter showed a near-significant trend, with responders having a larger mean diameter (mean 25.39 mm, SD 13.61) vs non-responders (mean 17.56 mm, SD 3.66), with P-values of 0.036 (1-sided) and 0.073 (2-sided). Conclusion: The significant differences in DI between responders and non-responders suggest that DI could be a key predictor of symptomatic response to intrapyloric BT injection. Further research with larger sample sizes is needed to validate its role in personalized treatment strategies for gastroparesis.Figure 1.: Pyloric diameter in idiopathic gastroparesis patients: responders vs non-responders to pyloric botox injection.

  PublisherDOI

• S2323 Addressing an Emerging Clinical Need: Nasal Metoclopramide's Impact on Diabetic Gastroparesis in Patients Taking GLP-1 Agonists

  The American Journal of Gastroenterology · 2024-10-01

  article1st authorCorresponding
  PublisherDOI

• Cardiac Biomarkers In Amyloidosis Predict Small Intestinal Bacterial Overgrowth

  Journal of Cardiac Failure · 2024-01-01

  article
  PublisherDOI

• HEART TO GUT: ILLUMINATING THE PATH FROM CARDIAC BIOMARKERS TO GASTROINTESTINAL COMPLICATIONS IN AMYLOIDOSIS

  Journal of the American College of Cardiology · 2024-04-01

  article
  PublisherDOI

Frequent coauthors

• Todd P. Coleman

  Stanford University

  25 shared

• Mark Pimentel

  16 shared

• Ryan C. Broderick

  University of California, San Diego

  13 shared

• Jeffrey L. Conklin

  12 shared

• Bryan J. Sandler

  University of California, San Diego

  12 shared

• Santiago Horgan

  12 shared

• Ravinder K. Mittal

  11 shared

• Armen A. Gharibans

  University of Auckland

  11 shared

Education

• Ph.D., Molecular Biology

  University of California, San Diego

  1991

• B.S., Biology

  University of California, San Diego

  1986