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Meet Rheumatologist ‘Will’ O’Brien, MD


Pentucket Medical welcomes William “Will” O’Brien, MD, who began practicing from our Haverhill office on September 9th.

As a rheumatologist, Dr. O’Brien specializes in the management and treatment of ailments of the joints, including all kinds of arthritis, gout, osteoarthritis and lupus.

He grew up in a military family, his father a West Point graduate. After living in many locations, his family settled in Portland, ME, and Will went on to undergraduate studies and a degree from Tufts University.

After Tufts, he entered Albert Einstein College of Medicine in the Bronx.

“I explored a career in research,” he says, “but decided I wanted to work with people. Einstein has a deep focus on social medicine, and I just loved the community there. I was drawn to immunology, and systemic autoimmune diseases tend to fall into rheumatology. It’s a subspecialty that’s a good fit for me.”

After receiving his MD from Einstein, Dr. O’Brien returned to New England for a Fellowship at Brigham & Women’s Hospital. His Haverhill practice is his first out of fellowship.

Dr. O’Brien says that his subspecialty is one that relies heavily on referrals.

“As a rheumatologist I’m definitely a doctor’s doctor, we get lots of referrals from other subs. It’s a specialty that takes some humility, because we often don’t know immediately what the diagnosis is. I work with patients to get them a comprehensive, compassionate treatment plan that will get them some function.”

He is glad to be starting his medical career here.

“Pentucket is a wonderful practice and a great fit for me,” he says. “The clinical managers are phenomenal…I get the sense that the clinic is very well run, and the tools are in place for me go above and beyond what I had hoped for. The things that I have to adjust for are minimal. Carolyn (Grasso) and Renee (Antolewicz) have been able to personalize my EMR and this going to be really impactful.”

“There are lots of rheumatologists in the Boston area, but I feel the Merrimack Valley is an area the needs rheumatology.” he says. “As the population ages, this will be more and more the case. I could see developing an arthritis department at Pentucket.”