Behavioral Health and Psychiatry Services

Stony Brook Medicine is the premier provider of behavioral healthcare and substance use treatment for Eastern Long Island and Suffolk County. Stony Brook Eastern Long Island Hospital is Suffolk County’s only facility that offers integrated care that encompasses detox, rehabilitation and psychiatry, along with medical care for other problems such as diabetes and liver disease, with a track record of proven success on the North Fork.

SBELIH’s behavioral health services take a holistic approach to providing the highest caliber medicine, psychiatry and substance use treatment under one roof for an individualized inpatient and outpatient treatment experience for substance use and psychiatric conditions in Suffolk County. We don’t define our patients by their addiction or psychiatric diagnosis, as they are not the equivalent of it.

Services include inpatient and outpatient Addiction Services under the Quannacut program and inpatient Psychiatry for Adults 18+. The philosophy of “Quannacut” (the Native American word for “hope’’ or “rainbow”) addresses addiction/chemical dependency as a treatable disease. SBELIH’s Behavioral Health Center is a place where our compassionate professionals work to maintain a nurturing environment that enables patients to stabilize, recover, and transition back into the community. 

Inpatient Services


Outpatient Services


Inpatient Psychiatry

All Quannacut Inpatient Services are provided at Stony Brook Eastern Long Island Hospital in Greenport, NY.

  • Inpatient Rehabilitation
  • Inpatient Detoxification
  • Medication Assisted Treatment (MAT)
  • Medication Management Services
  • Group/Individual Therapy
  • Recreation and Creative Arts Therapy

Located in Riverhead, NY, Quannacut Outpatient Services is a 14,000 square foot state-of-the-art behavioral health facility at the forefront of modern treatment for substance use disorders across Eastern Long Island. Off-site locations in Southampton and Greenport.

  • Advanced Integrated Treatment
  • Outpatient Psychiatry
  • Medication Assisted Treatment (MAT)
  • Medication Management Services
  • Group/Individual Therapy
  • Primary Care Medical Services
  • Recovery Homes

SBELIH Inpatient Psychiatry Services includes:

  • Comprehensive care in a healing and therapeutic environment
  • Medication management 
  • Group and individual therapy
  • Discharge planning to assist patients in their stabilization process
  • Psychiatry Residency Program



Lloyd Simon, MD

Lloyd Simon, MD
Director of Addiction Services

Diplomate, American Board of Internal Medicine
Diplomate, American Society of Addiction Medicine

Southold, (631) 765-4150