Lawrence Walser, MD

Internal Medicine & Pulmonology

185 Old Country Rd., Suite 3, Riverhead, NY 11901
To make an appointment, call: 631-727-2523

Office Hours

Monday – Friday


  • Internal Medicine
  • Pulmonology
  • Critical Care

A native-born Long Islander, Dr. Walser is one of Suffolk County's most distinguished physicians. A former Chief of the Departments of Medicine at Eastern Long Island Hospital and Peconic Bay Medical Center, he currently serves as Medical Director of Peconic Bay Medical Center's Intensive Care Unit and Department of Respiratory Care.

Fellowship-trained in Pulmonary-Critical Care, Dr. Walser is Board-Certified in Internal Medicine, as well as in the Sub-Specialties of Pulmonary Disease and Critical Care.

Dr. Walser has often been honored for his contributions and accomplishments as a physician and pulmonologist, including as a "Top Doctor" for 2014 by US News & World Report.

Board Certifications

American Board of Internal Medicine

American Board of Internal Medicine: Pulmonary Disease Subspecialty

American Board of Internal Medicine: Critical Care Subspecialty

National Board of Medical Examiners

Medical Training

SUNY Downstate College of Medicine, Brooklyn NY


Fellowship in Pulmonary-Critical Care, SUNY Stony Brook University Medical Center, Stony Brook, NY

Medical Associations

American College of Chest Physicians

American Thoracic Society

Hospital Affiliations

  • Peconic Bay Medical Center
  • Eastern Long Island Hospital