Physicians

Homan A. Zadeh M.D., M.P.H.

Dr. Zadeh graduated from Palm Springs High School in 1987. He finished his Bachelor of Science degree from University of California Irvine in 1991. He then went on to Wayne State University and received his MD degree in 1995. He came back to University of California Irvine for his internship and residency in internal medicine and his fellowship in gastroenterology from 1995 to 2001. He also received his Masters in Public Health from UCLA in 2001.

He is the Section Chief of Gastroenterology at Desert Regional Medical Center since 2012. He performs Upper Endoscopy, Colonoscopy, Endoscopic Retrograde Cholangiopancreatography (ERCP), Percutanous Endoscopic Gastrostomy Placement (PEG), and Capsule Endoscopy. He is the first Gastroenterologist in the Coachella Valley to perform fecal transplant procedure for a patient with reccurent c. diff. Infection.

He was the first Gastroenterologist in the Coachella Valley to perform the ReShape weight loss procedure. He has a special interest in treating patients with various liver diseases, especially Hepatitis C. Board Certified in both Internal Medicine and Gastroenterology, he is also an Assistant Clinical Professor at Western University of Health Sciences.

Martin J. Collen, MD, MBA

Dr. Collen is an internationally recognized physician who was born in Oakland, California and grew up in Los Angeles. During the more than 30 years of Dr. Collen’s training and academic association in medicine, he has authored more than 250 original research and review publications, including books, articles, and abstracts. He graduated with a B.A. in Mathematics from UCLA in 1966, and attended Chicago Medical School at Rosalind Franklin University School of Medicine and Science, Chicago, Illinois, graduating in 1970 with an MD degree. He completed a year of internship in medicine and a year of residency in general surgery at UC, Irvine, and then went on to complete an additional two years of residency in Internal Medicine and two years of fellowship in Gastroenterology at UCLA, finishing in 1977. He was an Assistant Professor of Medicine at UC, Irvine from 1977-1980, and was Instructor of the Year for two successive years. He completed a research fellowship in Gastroenterology from 1980-1985 at the National Institutes of Health in Bethesda, Maryland, and was Associate Professor of Medicine and Director of GI Research at Georgetown University Medical Center in Washington, DC from 1985-1990. He moved back to California in 1990, where he was Professor of Medicine at Loma Linda University from 1990-1995 and Clinical Professor of Medicine from 1995-2005. He earned an Executive MBA in Health Care from UC, Irvine in 1999. Dr. Collen has been in private practice as a Gastroenterologist since 1995. He is board certified in both Internal Medicine and Gastroenterology and is a Fellow of the American College of Physicians and the American College of Gastroenterology.

Matthew Elliott, PA-C

Matthew Elliott is a board-certified Physician Assistant who has been working in the medical field since 2004. A native Texan, he started his medical career earning his Associates Degree of Applied Science as an Emergency Medical Technician. A short time later, he became certified with the National Registry of Emergency Medical Technicians as a Paramedic in Lubbock, Texas in 2004. He returned to school and studied nursing at the Covenant School of Nursing and became a Registered Nurse in 2009. As a Registered Nurse, he worked in a variety of settings such as the Intensive Care Unit and Emergency Department. Matthew continued his education and graduated Magna Cum Laude with his Bachelor’s degree of Science in Biology at Lubbock Christian University while working as an RN in 2011. He then decided to take a break from school and traveled throughout California working as a travel nurse in a variety of hospitals from San Diego to San Luis Obispo. Matthew’s passion for medicine brought him back to the University of Texas Rio Grande Valley where he earned his Master’s in Physician Assistant Studies in 2017. Throughout his academic career, has been on the Dean’s and President’s lists for his exemplary academic abilities. He has been inducted in the Pi Alpha Honor Society for Physician Assistants and Phi Kappa Theta Mu- International Honors Society. He is a member of the California Academy of Physician Assistants and the American Academy of Physician Assistants.

Vijay Agarwal, MD

Dr Agarwal received his MBBS (Bachelor of Medicine & Bachelor of Surgery) degree in 1977 and MD (Doctor of Medicine) degree in 1981 from Kasturba Medical College, Mangalore, India. He migrated to the USA in 1983. He completed Internal Medicine Residency in 1987 from Framingham (Boston University) and Fellowship in Gastroenterology, Hepatology & Nutrition in 1989 from Veterans Administration Medical Center (Boston University). He joined University of New Mexico Medical Center in June 1989 as Assistant Professor of Medicine (Gastroenterology) and was in charge of Laparoscopy and Motility Studies. During his tenure there, he conducted basic research in “The Role of Short Chain Fatty Acids in Diversion Colitis” and “Role of Nuclear Magnetic Resonance in Hepatic Encephalopathy”. He joined FHP in December 1992 and was Section Chief from June 1993 until early 1996 until FHP closed its Specialty Clinics. He then formed his own practice group in Albuquerque, New Mexico and he practiced there until early 2019 . He performs all diagnostic and therapeutic endoscopic procedures including esophageal manometry, anorectal manometry and capsule endoscopy. He moved to Palm Springs, CA in 2019 to join Dr Homan Zadeh and Dr Martin Collen in their practice.

Elizabeth McGowan, DNP

Elizabeth McGowan, DNP, completed her Master’s Degree and Nurse Practitioner certification at Loma Linda University in 2002, and received her Doctorate of Nursing Practice in 2015. After working as an acute care and emergency room RN she began her practice as an NP in 2002 in a GI/Internal Medicine practice in Riverside. After completing her Doctorate with a specialty in Hereditary colon cancer syndromes, she relocated her practice to Palm Springs with Dr Zadeh in 2015. She maintains her membership in the California Association of Nurse Practitioners, having previously served as President and Vice President of the Inland Empire chapter. She also started the GI Advanced Practice group of the Inland Empire. She has been on staff at Desert Regional Medical Center, as well as Redlands Community Hospital, Parkview Community Hospital and Riverside Community Hospitals.

Mark Gabriel, DO

Dr. Mark Gabriel grew up in Denver, Colorado where he received a Bachelor’s Degree in Biology and Chemistry from the University of Colorado. He then moved to California to attend medical school at the Western University of Health Sciences. His post-graduate training was completed at Loma Linda University in Internal Medicine, followed by serving an additional year as Chief Medical Resident, and then a 3 year fellowship in Gastroenterology.

Dr. Gabriel has been practicing gastroenterology since 2000. He has served as associate clinical professor of medicine/gastroenterology at the University of California Riverside, School of Medicine. He now sees patients for gastroenterology-related concerns in La Quinta and Rancho Mirage. In his spare time, Dr. Gabriel enjoys spending time with his wife, family, and cats, cooking, gardening, and playing the guitar.

Medical Education: Western University of Health Sciences, DO

Residency: Loma Linda University, Internal Medicine

Fellowship Training: Loma Linda University, Gastroenterology

Alexandre Monteiro, NP

Born and raised in Brazil, I bring over 26 years of healthcare experience to my role as a Nurse Practitioner. With approximately 20 years dedicated to emergency medicine and over 5 years specializing in gastrointestinal health, I have developed a deep understanding of patient care in diverse and challenging environments.

Having lived in the desert for over 20 years, I have come to cherish the unique beauty of our magical winters. My passion lies in engaging with patients, empowering them with the knowledge and skills they need to effectively manage their conditions. I believe that education is key to improving health outcomes, and I strive to create a supportive atmosphere that fosters open communication and mutual respect.

I am committed to providing high-quality care and making a positive impact on the lives of my patients.

Bony Mathew, FNP- BC

Bony Mathew relocated from Chicago to Palm Springs during the COVID-19 pandemic while working as a travel nurse. His clinical background includes emergency medicine as a registered nurse, followed by advanced practice experience as a nurse practitioner in dermatology, hospice care, and currently in gastroenterology and hepatology.

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Call (760) 864-4163 or contact us online to schedule your appointment today.

Palm Springs Office

1330 N. Indian Canyon Drive Suite
Palm Springs, CA 92262

Phone: (760) 864-4163
Fax: (760) 864-4166

La Quinta Office

47120 Dune Palms Road Suite
109 La Quinta, Ca 92253

Phone: (760) 777-7544
Fax: (760) 777-7618