"He's extremely detailed," said Barbara Keeney, his receptionist since he entered private practice on July 1, 1970. "He can't answer a question with yes or no."
As September comes to a close, Gallager, 80, will hang up his stethoscope after more than 46 years of practicing medicine in Catonsville.
Toward the end of last year, his wife of 59 years, Ann, fell ill. Gallager knew his priorities had to change.
Retirement was not an easy decision, he said, but he knew it was for a good reason.
"That was it," he said. "It didn't take me long to realize that she might not make it, and that was really hard to think about. I didn't think I'd be able to practice medicine if she had passed away. That would just destroy me."
Originally from Paoli, Pa., Gallager grew up at 6209 Frederick Road, above the office of his father, a general practitioner.
As a child, he saw what doctors had to do. He'd hear his father get up in the middle of the night to take care of patients. Sitting next to his father at the dinner table, he learned how to talk to patients because some called during the meal. He'd accompany his father on rounds down Rolling Road.
He can count at least four generations of doctors in his family. When Gallager was deciding what to do for his career, there wasn't much to think about. He would follow the footsteps his family and study medicine.
"It was the only decision," he said. "There wasn't anything else to do in my world."
He got his medical degree at the University of Maryland School of Medicine in 1962, serving his internship and residency at University of Maryland's Baltimore hospital.
From 1964 to 1966, he had a fellowship in international medicine with the Pakistan Medical Research Medical Center and University of Maryland Hospital, which took him to Pakistan to study infectious diseases.
Shortly after he returned, he was drafted into the U.S. Army, where he served as a captain and staff internist in Europe. After a stint in Orleans, France, he went to Mons, Belgium, where he was in charge of outpatient emergency rooms and dispensaries for Belgium, Luxembourg and the Netherlands.
He returned to the United States in 1969. He was chief resident in medicine at St. Agnes Hospital from 1969 to 1970 before starting his private practice on July 1, 1970. The office was on Wilkens Avenue for 26 years, then Maiden Choice Lane for 12 before moving to Frederick Road, Keeney said.
He wanted to get to know his patients and build relationships.
According to the American Medical Association, there are 1,082 doctors who are practicing internal medicine in Baltimore County. Based on the 2010 population, that's a 744-to-1 ratio of doctors to people.
While that ratio may include doctors who are not practicing, it's a good ratio for access to care, according to Gene Ransom, CEO of MedChi, the Maryland State Medical Society. He noted there are physician shortages in certain parts of the state, including rural areas and Prince George's County.
But what brings concern to Ransom is the belief that primary-care medicine is not a popular choice among new doctors, as they choose to go into specialized care.
Specialists tend to make more money, two to three times the salary of primary care physicians, he said. With rising costs of medical school, students may be graduating with $500,000 in debt, he said.
"If you're only going to make $150,000 or $200,000 as a primary care doctor and you can make significantly more with a specialty, you can see where they would choose those specialties," he said. "That's a fundamental issue."
According to a 2015 report from the Association of American Medical Colleges, there will be a national shortage of between 12,500 and 31,100 primary care physicians by 2025, while there will be a shortfall of between 28,200 and 63,700 specialists. It's an issue now, the nonprofit argues, because training for these positions can take up to a decade.
None of Gallager's five children is in internal medicine, though two are physical therapists. Four of his nine grandchildren are in nursing.
While Gallager said he was disappointed that his children did not become internal medicine specialists, he understands why.
"You don't make a lot of money doing what I do, but I love what I do and I've loved what I've done," he said.
During his career, the profession has changed dramatically. Technology has made once-complicated procedures routine. Bioengineering has created new drugs and therapies, some using a patient's genes to fight diseases. AIDS came on the scene, antibiotic-resistant bacteria are posing new challenges and a surge in travel has heighten fears about the spread of Ebola and Zika viruses.
The doctor's day
A typical day for Gallager starts at 2:30 in the morning. Sometimes he'll sleep in, awaking at 3.
He spends the first few hours feeding his dog, Jack — a foot tall and fluffy, he's an 11- or 12-year old rescue dog who is blind and diabetic — and doing homework in the kitchen of his Ellicott City house, focusing on records and annual exams.
He would arrive at the office around 6 a.m. and open its doors at 7. He'd plan enough time to see a patient for as long as necessary. Annual reviews merited a two-hour spot while office visits were set for between half-an-hour to an hour. He records everything he observes for his annual reports.
"We really get to know each other real well and I think that's what patients love," he said.
Before his wife fell ill, he'd arrive home at 5 or 5:30 p.m. Often times, his pager would go off, a signal that a patient was in need. One way or another, he'd have to go back to the office. It was just a matter of whether he'd go straight there or stop and eat a quick dinner first.
Since then, he has cut back his hours. Now, he works what he calls half days — eight hours — getting home in time to make Ann lunch and keep her company throughout the afternoon.
He'll often end his days watching "Dancing with the Stars" or "America's Got Talent" and go to sleep around 10 p.m. before starting the process over again.
While doctors may counsel people to get eight hours of sleep a night, he says he gets enough.
"I don't sleep much at night," he said. "Hardly an hour goes past that I don't know it."
Gallager, at one point, had as many as 2,000 patients, Keeney said. After he switched his practice to concierge medicine — in which patients pay an annual fee to join — he's had about 300 patients for the last eight years.
Patients have come to appreciate his thoroughness. Gallager has a sense of pride when he picks up a patient's annual report, knowing that they could go anywhere in the world where English is spoken with it and have a doctor understand their medical history.
"He explains what's happening to you in your body and he literally takes you on a virtual tour of the inside of your body," said Cathy Arini, of Catonsville, a patient of Gallager's for 40 years. "It's amazing. He makes me want to study anatomy."
His patients say it will be hard to replace Gallager.
"I was very disappointed," said 82-year-old Margaret Redman, of Lansdowne, a patient since about the time Gallager started his practice. "I wanted to be the one who was gone before he was."
The doctor has recommended other local doctors to his patients.
"Sadly there aren't many like him anymore," said Barbara Shoemaker, 70, of Halethorpe, a patient for 30 years. "He's not in it for the money, he's in it for his patients. His patients mean the world to him."
A difficult farewell
Gallager says he doesn't make friends easily. But over the course of his career, he has been able to make patients easily.
John Fischer, 88, of Ellicott City, has seen Gallager for 20 years, after the doctor's brother, Wilmer, also a Catonsville internal medicine specialist, retired.
He said Gallager treats him like a friend.
"Some doctors aren't that way," Fischer said. "Some doctors are all business. But Dr. Gallager is very friendly."
Friend is a word that Gallager has used only recently to describe his longtime patients. Over the course of his career, he made it a point to keep his doctor-patient relationships professional.
"But behind that was a friendship which never was revealed until now," he said.
All of a sudden, Gallager and his patients are on first-name basis. As they say goodbye to him for what may be the final time, they're crying. He tries not to.
Patients have asked Keeney to take photos of them with Gallager. Some get photos with his entire staff.
He is saying goodbye "to a whole herd of best friends," which is something he acknowledges as difficult. And it's something that's going on every day.
When it happens, the inevitable question is asked: What will he be doing next?
He doesn't know, for sure. But there are some things he knows will happen.
He'll focus on his family. He plans to continue helping his wife as she recovers. He's eager for his family to visit his home for Christmas, counting 24 people who will be there.
He wants to fix up his basement, which was damaged when Ellicott City was flooded in July.
And he knows what he won't do. He won't return to medicine, not even part-time. He only wants to practice when he's at the top of his game, which he believes is not possible on a part-time basis.
"There's no coming back," he said. "That is over."
His last day seeing patients is Sept. 30, he said. He'll use October to "pick up the pieces" — a phrase he used to describe addressing last-minute issues and questions from patients, he said, will inevitably have — and pack up his office.
Until then, patients will continue to visit him at the Catonsville Professional Center and say "congratulations" on his retirement.