Board Certified · Nephrology
Sharmini Jayamaha, M.D.
Kidney specialist close to home.
For 25 years, Dr. Jayamaha has cared for the kidney health of Long Island's East End — from chronic kidney disease and hypertension to dialysis — with offices in Greenport and Riverhead.
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Two offices, one practice
Where to find us this week
Dr. Jayamaha sees patients at both offices on a fixed weekly schedule — Riverhead on Monday, Wednesday, and Friday; Greenport on Tuesday and Thursday. Both offices are open 10 am to 5 pm.
Greenport office
Tuesdays & Thursdays · 10 am – 5 pm
Greenport, NY 11944
Riverhead office
Mondays, Wednesdays & Fridays · 10 am – 5 pm
Riverhead, NY 11901
About the doctor
25 years of kidney care on the East End
Dr. Sharmini Jayamaha is a board certified nephrologist who has served the North Fork and greater East End community for 25 years. She provides comprehensive care for the full range of kidney conditions — helping patients manage chronic kidney disease, protect kidney function alongside diabetes and high blood pressure, and navigate dialysis when needed. She provides regular attending nephrology care at three East End dialysis centers — East End Dialysis Center and DaVita Peconic Bay Dialysis in Riverhead, and the Southampton Hospital Regional Dialysis Center (Barbara H. Lord Regional Dialysis Center) in Hampton Bays — so patients can continue seeing their own nephrologist throughout in-center dialysis.
- SpecialtyNephrology (kidney medicine), board certified
- Medical schoolUniversity of Colombo / University of Kelaniya Faculty of Medicine
- ResidencySUNY Downstate Medical Center, Brooklyn, NY
- FellowshipNephrology — Stony Brook University Hospital, Stony Brook, NY
- Hospital affiliationsStony Brook Eastern Long Island Hospital · Peconic Bay Medical Center · Stony Brook University Hospital
- Dialysis centersEast End Dialysis Center (Riverhead) · DaVita Peconic Bay Dialysis (Riverhead) · Southampton Hospital Regional Dialysis Center (Hampton Bays)
- In practice25 years, serving Greenport, Riverhead, and the surrounding East End communities
Conditions & services
What we treat
Dr. Jayamaha provides diagnosis and ongoing management for kidney disease at every stage, in close coordination with your primary care physician.
Kidney disease
- Chronic kidney disease (all stages)
- Acute kidney injury & failure
- Glomerulonephritis & nephropathy
- Polycystic kidney disease
- Nephrotic syndrome & proteinuria
- Kidney stones & kidney infections
Dialysis
- Hemodialysis management
- Peritoneal dialysis (CAPD)
- End-stage renal disease care
Dr. Jayamaha rounds as an attending nephrologist at East End Dialysis Center (Riverhead), DaVita Peconic Bay Dialysis (Riverhead), and the Southampton Hospital Regional Dialysis Center (Hampton Bays).
Related conditions
- Hypertension & hypertensive kidney disease
- Diabetes-related kidney disease
- Electrolyte & mineral disorders
- Anemia of chronic kidney disease
- Gout & hyperparathyroidism
- Vitamin D deficiency
Insurance & Medicare
The practice accepts Medicare assignment and participates with major insurance plans. Because coverage varies, please call the office to confirm that your plan is accepted before your first visit.
Common questions
Frequently asked questions
Answers for patients across Riverhead, Greenport, Southampton, Hampton Bays, and the North Fork.
Is there a nephrologist in Riverhead, NY?
Yes. Dr. Sharmini Jayamaha, a board certified nephrologist, sees patients at 632 Roanoke Avenue in Riverhead on Mondays, Wednesdays, and Fridays from 10 am to 5 pm. Call (631) 208-8270 to make an appointment.
Is there a kidney specialist in Greenport or on the North Fork?
Yes. Dr. Jayamaha's Greenport office at 222 Manor Place, Suite 102 serves Greenport, Southold, Mattituck, Cutchogue, Shelter Island, and the surrounding North Fork communities. Office hours are Tuesdays and Thursdays, 10 am to 5 pm. Call (631) 477-1755.
Do you see patients from Southampton and Hampton Bays?
Yes. Many of our patients come from Southampton, Hampton Bays, and across the East End. The Riverhead office is a short drive from both, and Dr. Jayamaha is affiliated with Peconic Bay Medical Center in Riverhead.
Is there a nephrologist on the East End of Long Island?
Yes. East End Nephrology, P.C. is a dedicated nephrology practice on the East End, led by board certified nephrologist Dr. Sharmini Jayamaha. With offices in Riverhead and Greenport, the practice has provided kidney care across the East End of Long Island for more than 30 years.
What is the difference between nephrology and a nephrologist?
Nephrology is the medical specialty devoted to the kidneys; a nephrologist is a physician who practices nephrology. Whether you search for "nephrology near me" or "nephrologist near me," you're looking for the same thing — a kidney specialist. Dr. Jayamaha is a board certified nephrologist practicing nephrology in Riverhead and Greenport, NY.
Does Dr. Jayamaha accept Medicare?
Yes. The practice accepts Medicare assignment, meaning the Medicare-approved amount is accepted as payment in full for covered services. The practice also participates with major insurance plans — call the office to confirm your specific plan.
Do I need a referral to see a nephrologist?
A referral from your primary care physician is helpful but not always required — though your insurance plan may require one. Call the office and the staff will advise you.
What conditions does a nephrologist treat?
A nephrologist is a medical doctor who specializes in kidney care — including chronic kidney disease, acute kidney injury, dialysis, hypertension, diabetes-related kidney disease, kidney stones, and electrolyte disorders.
Appointments
Make an appointment
Appointments are scheduled by phone. Call the office for the location most convenient to you, and have your insurance card and a list of your current medications ready. New patients: a referral from your primary care physician is helpful but not always required — the office staff can advise you when you call.